Toward a national consensus: teaching radiobiology to radiation oncology residents

PII S0360-3016(02)02968-1

BIOLOGY CONTRIBUTION

TOWARD A NATIONAL CONSENSUS: TEACHING RADIOBIOLOGY TORADIATION ONCOLOGY RESIDENTS

ELAINE M. ZEMAN, PH.D.,* JOSEPHR. DYNLACHT, PH.D.,† BARRY S. ROSENSTEIN, PH.D.,‡ AND

MARK W. DEWHIRST, D.V.M, PH.D.,§ ON BEHALF OF THE ASTRO JOINT WORKING GROUP ON

RADIOBIOLOGY TEACHING

*Department of Radiation Oncology, University of North Carolina School of Medicine, Chapel Hill, NC;†Department of RadiationOncology, Indiana University School of Medicine, Indianapolis, IN;‡Department of Radiation Oncology, Mount Sinai School of

Medicine and New York University School of Medicine, New York, NY;§Department of Radiation Oncology,Duke University School of Medicine, Durham, NC

Purpose: The ASTRO Joint Working Group on Radiobiology Teaching, a committee composed of membershaving affiliations with several national radiation oncology and biology-related societies and organizations,commissioned a survey designed to address issues of manpower, curriculum standardization, and instructorfeedback as they relate to resident training in radiation biology.Methods and Materials: Radiation biology instructors at U.S. radiation oncology training programs wereidentified and asked to respond to a comprehensive electronic questionnaire dealing with instructor educationalbackground, radiation biology course content, and sources of feedback with respect to curriculum planning andresident performance on standardized radiation biology examinations.Results: Eighty-five radiation biology instructors were identified, representing 73 radiation oncology residencytraining programs. A total of 52 analyzable responses to the questionnaire were received, corresponding to aresponse rate of 61.2%.Conclusion: There is a decreasing supply of instructors qualified to teach classic, and to some extent, clinical,radiobiology to radiation oncology residents. Additionally, those instructors with classic training in radiobiologyare less likely to be comfortable teaching cancer molecular biology or other topics in cancer biology. Thus, a gapexists in teaching the whole complement of cancer and radiobiology curricula, particularly in those programs inwhich the sole responsibility for teaching falls to one faculty member (50% of training programs are in thiscategory). On average, the percentage of total teaching time devoted to classic radiobiology (50%), clinicalradiobiology (30%), and molecular and cancer biology (20%) is appropriate, relative to the current makeup ofthe board examination. Nevertheless large variability exists between training programs with respect to the totalnumber of contact hours per complete radiobiology course (ranging from approximately 10 to >50 h). A numberof lecture topics, particularly in clinical radiobiology, are covered by fewer than 60% of training programs. Asizeable minority of radiation biology instructors are dissatisfied with the feedback they receive with respect toboth course content and the performance of their residents on standardized radiobiology examinations admin-istered by the American College of Radiology and/or the American Board of Radiology. © 2002 Elsevier ScienceInc.

Radiation biology teaching, Radiation oncology education, Instructor survey, ASTRO Joint Working Group onRadiobiology Teaching.

INTRODUCTION

The kind of biology that practicing radiation oncologistsneed to know to better understand modern cancer treatmenthas changed dramatically in recent years, with the explosion

of new knowledge as to the molecular underpinnings ofcancer. Accordingly, radiation biology educators have be-gun to include so-called molecular oncology topics (definedhere as the terminology, techniques, pertinent findings, andclinical implications/applications of the new molecular and

Support for the conduct of this survey and the initial analysis ofthe results were provided by ASTRO.

Presented in part at the 42nd Annual Meeting of the AmericanSociety for Therapeutic Radiology and Oncology, Boston, MA,October 21, 2000; and at the 48th Annual Meeting of the RadiationResearch Society, San Juan, PR, April 23, 2001.

Reprint requests to: Elaine M. Zeman, Ph.D., Department ofRadiation Oncology, Campus Box 7512, University of NorthCarolina School of Medicine, Chapel Hill, NC 27599-7512.

Tel: (919) 966-7713; Fax: (919) 966-7681; E-mail: [email protected]—The authors thank the fellow members of theASTRO Joint Working Group on Radiobiology Teaching for theirvaluable comments, criticisms, and suggestions regarding thismanuscript.

Received Jan 22, 2002, and in revised form May 15, 2002.Accepted for publication May 24, 2002.

Int. J. Radiation Oncology Biol. Phys., Vol. 54, No. 3, pp. 861–872, 2002Copyright © 2002 Elsevier Science Inc.Printed in the USA. All rights reserved

0360-3016/02/$–see front matter

861

cancer biology) into their teaching repertoires. In so doinghowever, a number of questions arise, including:

1. How much, which specific topic areas, and in what depthand context should molecular oncology be presented toradiation oncology residents?

2. To what extent should new material be integrated into anexisting radiation biology course (e.g., should new in-formation either replace, or supplement, “older knowl-edge” of classical concepts in radiobiology)? Shouldmolecular-based therapies be taught alongside more tra-ditional clinically oriented topics such as radiosensitizersand radioprotectors, time–dose–fractionation patterns,radiation and chemotherapy interactions, etc.?

3. What should the overall goals be in teaching radiationand cancer biology to radiation oncology residents in the21st century? Should residents be taught by focusing onknowledge that allows them merely to pass their certifi-cation examinations? To gain an appreciation of the rolesradiation and cancer biology play in day-to-day clinicalpractice? To acquire the skills necessary to understandand participate in translational research? All of theabove? Should training programs likewise be obligatedto train a future generation of academic radiation oncolo-gists and/or physician scientists, even though a largemajority of their graduates ultimately enter private prac-tice?

Although these may seem like relatively straightforwardissues to address, answers to such questions are in fact quiteelusive. Furthermore, only a paucity of publications in re-cent years have even attempted to address this situation(1–3). A sizeable “disconnect” occurs between the variouscommittees and organizations charged with resident educa-tion and physician and training program certification and theactual educators themselves. Part of this is created by theBoard Examination Process, which for accreditation pur-poses must be administered by an independent certificationorganization, the American Board of Radiology (ABR).One of the obvious missions of the American Society forTherapeutic Radiology and Oncology (ASTRO) is the ed-ucation of its junior members and continuing education ofthe remainder of its membership. Typically, the actualteaching of cancer and radiobiology to radiation oncologyresidents becomes the responsibility of the radiobiologyfaculty members at each institution. Most of these individ-uals are not members of ASTRO and do not regularly attendthat meeting. The primary society that most of these indi-viduals belong to is the Radiation Research Society (RRS).

The actual certification exams, which are administered atthe completion of residency, are conducted by the ABR.Board certification involves the successful completion of arigorous written board examination in clinical radiationoncology, radiologic physics, and radiation and cancer bi-ology, followed �1 year later by an oral examination em-phasizing clinical skills. The ABR distributes to residencytraining program directors and incoming residents a pam-phlet titled “Booklet of Information for Radiation Oncol-

ogy” (4), which contains an outline of all content areas—including radiobiology—deemed suitable for inclusion onthe written board examination. Ten-year recertification ofpracticing radiation oncologists, beginning with 1995 grad-uates, is also under the auspices of the ABR (4). TheAmerican College of Radiology (ACR), on the other hand,monitors the educational progress of radiation oncology(and radiology) residents during residency. Annually, mostresidents in the United States take the ACR’s in-trainingwritten examination in clinical radiation oncology, radio-logic physics, and radiation/cancer biology. In some cases,training programs gauge resident performance (and to someextent, the success of their own didactic teaching programs)on the basis of residents’ scores on successive, annualin-training exams. The ABR and ACR deliberately limittheir interactions with each other so as to avoid any per-ceived conflict of interest. For example, they do not shareexam questions nor should exam question writers or com-mittee members serve both organizations simultaneously.

The ABR and ACR are not the only other organizationsinvolved either directly or indirectly in the education ofradiation oncology residents, however. The Radiation On-cology Residency Review Committee (RRC) of the Accred-itation Council for Graduate Medical Education (ACGME),for example, is responsible for accrediting radiation oncol-ogy residency training programs in the United States (5).Achievement of accreditation requires that each trainingprogram meet or exceed minimal ACGME standards withrespect to administrative structure, facilities, faculty, patientresources, and educational environment, to ensure properresident education and training. The ACGME stipulates thatthe training program faculty must include at least one full-time, on-site, radiation biologist or basic scientist responsi-ble for teaching radiation biology to residents. However,what the radiation biology curriculum should consist of,beyond “all aspects of radiation effects on normal andneoplastic tissues,” is not otherwise specified (5).

Another organization that sometimes shares memberswith the ACR, ABR, and/or RRC, and may or may not haveinput into educational curricula and policies, is the Societyof Chairmen of Academic Radiation Oncology Programs(SCAROP) (3). In some cases, SCAROP members alsoserve as residency training program directors. Finally, an-other group with an obvious “vested interest” in educationalmatters—albeit with limited, if any, input—is the Associa-tion of Residents in Radiation Oncology (ARRO). ARROreceives much of its administrative support and funding forits activities from ASTRO.

To summarize, individual program teaching is done byfaculty who are not usually members of ASTRO. ASTROfeatures didactic sessions—“ refresher courses”—at its an-nual meeting as a form of Boards preparation for residents,as well as continuing education for other members. It alsosponsors other educational activities in the form of smaller,more focused meetings. Testing during residency training,and credentialing at the completion of training, are handledby different organizations, the ACR and ABR, respectively,

862 I. J. Radiation Oncology ● Biology ● Physics Volume 54, Number 3, 2002

which are independent of ASTRO and RRS. Meanwhile, theRRC is charged with accrediting residency training pro-grams and ensuring that minimum educational standards,including those in radiation and cancer biology, are met.

Where does the radiation or cancer biologist employed bya radiation oncology department fit into this scheme ofsomewhat ambiguous, overlapping “ jurisdictions”? In theoverwhelming majority of cases, the basic scientist is hiredprincipally to develop a productive, extramurally fundedresearch program. Other job responsibilities include servingas mentors to graduate students, postdoctoral fellows, clin-ical research fellows, and residents, taking part in variousadministrative or organizational tasks at the departmentaland institutional levels and beyond, and finally, teachingradiation/cancer biology to residents (among others). Howhigh a priority each of these ancillary job responsibilities isgiven often varies depending on individual, departmental,and institutional priorities. The survey clearly indicated thatmany biology instructors do not have knowledge of, oraccess to, the ABR publication “Radiation Oncology Resi-dent Training Guidelines for Cancer and Radiation Biol-ogy” (4). One section of the booklet deals with the scope ofrequired knowledge in cancer and radiobiology. Further-more, the extent of the biology instructor’s participation inthe training program accreditation process is usually littlemore than providing a curriculum vitae and a recent sylla-bus for the existing biology course. Indeed, some instruc-tors—including the authors—have had the experience ofnot being requested to meet with RRC-designated site vis-itors during the program’s accreditation review. Further-more, the accreditation guidelines do not provide any spe-cifics as to what would be considered an acceptable syllabusfor resident trainees.

Radiation and cancer biology instructors are much morelikely to be members of research-oriented societies, such as

the RRS or the American Association of Cancer Research(AACR), than ASTRO. They typically have little or noknowledge of the intricacies of the relationships among theACR, ABR, RRC, and others. Most do not attend the annualASTRO meeting. Although the RRS and AACR also fea-ture “education” as part of their mission statements, andlikewise sponsor educational activities at their nationalmeetings, the education of radiation oncology residents isnot mentioned specifically, nor has it historically been ahigh priority in these societies. This is perhaps understand-able given that the RRS is not involved formally in theactivities of either the ACR or ABR (or RRC), exceptinsofar as select members of the RRS are asked to composeradiation biology questions for the in-training or writtenboard exams.

Thus, biology teachers often find themselves frustratedand isolated when it comes to clearly defining what radia-tion oncology resident teaching curricula should encom-pass. The area of molecular oncology in particular demandsspecial attention, because it is such a rapidly changing field.However, uncertainties also exist with respect to the moretraditional areas of “classical” and “clinical” radiobiologyas well.

The ASTRO Joint Working Group on RadiobiologyTeaching Committee, a committee composed of membershaving affiliations with many of the radiation oncology andbiology-related societies and organizations mentionedabove, has been formed to address some of these issues. Themembers of this committee, along with some of their otherassociations and contact information are included in Table1. We report the results of a national survey of radiation andcancer biology instructors employed by accredited radiationoncology training programs in the United States, developedby the Joint Working Group on Radiobiology Teaching.The survey represents only one of several committee activ-

Table 1. Membership roster and contact information for the ASTRO Joint Working Group onRadiobiology Teaching

MemberSociety/committee

affiliations Contact information

Mark Dewhirst, Committee Chair ASTRO, RRS [email protected] Dynlacht ASTRO, RRS [email protected] Giaccia ASTRO, RRS [email protected] Hall ASTRO, RRS, ABR [email protected] Hughes ASTRO, ARRO [email protected] Kang ASTRO, ARRO [email protected] Lawton ASTRO, RRC [email protected] Leibel ASTRO, SCAROP, ABR [email protected] Olkin ACR [email protected] Rosenstein ASTRO, RRS, ACR [email protected] Withers ASTRO, RRS, ABR [email protected] Zeman ASTRO, RRS [email protected]

Abbreviations: ASTRO � American Society for Therapeutic Radiology and Oncology; RRS � RadiationResearch Society; ABR � American Board of Radiology; ARRO � Association of Residents in RadiationOncology; ACR � American College of Radiology; RRC � Residency Review Committee of the Accredi-tation Council for Graduate Medical Education; SCAROP � Society of Chairmen of Academic RadiationOncology Programs.

863Radiation biology teaching survey ● E. M. ZEMAN et al.

ities that have already taken place or are planned for thefuture.

METHODS AND MATERIALS

A comprehensive questionnaire was developed by one ofus (E.M.Z.) partially in response to a preliminary, limitedsurvey of radiation biology instructors known to be in-volved in resident education conducted by Dr. Janet Raseyof the Department of Radiation Oncology, University ofWashington, Seattle, WA, in October 1999. The results ofthis preliminary survey were presented at a symposiumtitled “Teaching Radiobiology in the New Millennium” heldin conjunction with the 42nd Annual Meeting of ASTRO inBoston, MA during October 2000. Audience comments andsubsequent feedback also figured prominently in the devel-opment of the new questionnaire, which was finalized inJanuary 2001.

The questionnaire consisted of 33 items, organized intothree categories: instructor “demographics” (8 questions oneducational background, teaching workload, and attitudestoward teaching), radiation/cancer biology course content(18 questions), and instructor feedback and satisfaction (7questions related to feedback received with respect tocourse content and resident performance on standardizedexaminations). The survey questions were of three types,including “multiple choice, one best answer,” “ multiplechoice, indicate all that apply,” and “ rank items on a scaleof 1–5.” Responses that did not adhere to the format of thequestion—for example, a “one best answer” -type questionfor which multiple responses were indicated—were notincluded in the final tally of results. The results of questionscalling for a single response were expressed as the percent-age of the total number of responses, and questions thatcalled for multiple responses or rankings were expressed asthe percentage of the total number of respondents whoindicated that particular choice.

To generate a mailing list for the radiobiology instructorsurvey, U.S. radiation oncology training program directorswere contacted by the ASTRO administrative office andasked to provide contact information for their respectiveradiation biology teaching faculty. A total of 85 individualswere identified, representing 73 accredited training pro-grams. Participation in the survey was done by respondingto an electronic version of the questionnaire.

RESULTS

Of the 85 radiation biology instructors who received theE-mail questionnaire, a total of 52 responses were receivedby March 1, 2001, corresponding to an overall response rateof 61.2%. Perhaps indicative of some of the “disconnect”problems faced by instructors, an additional 9 individualswere identified in the 2 months after completion of thesurvey, who expressed consternation that they had not beenincluded on the original mailing list. Approximately one-half of these commented that they suspected that their

residency training program directors did not pass on theinformation to them so that they could participate.

All instructors receiving the E-mail questionnaire, plusthose identified subsequently, were added to an ASTRO-moderated electronic mailing list ([email protected]), for the purposes of disseminating impor-tant teaching-related information and promoting the freeexchange of ideas and educational resources among the listparticipants.

Instructor “demographics”Of the survey respondents, 89.7% hold a Ph.D. or equiv-

alent, including 2.0% D.V.M./Ph.D. and 6.1% M.D./Ph.D.An additional 8.2% of respondents hold the M.D. degree,and 2.1% indicated “other” without further elaboration (al-though options such as “M.A./M.S./M.P.H,” and so forthwere also available choices). Figure 1 shows the distribu-tion—sorted by decade—of when instructors received theirhighest academic degree. Approximately 27.4% receivedtheir highest degree between 1960 and 1969; 27.4% be-tween 1970 and 1979; 31.4% between 1980 and 1989; and13.7% between 1990 and 1999.

When asked what specialty their highest degree was inand/or what they consider themselves to be, approximately63.5% of radiobiology instructors identified themselves as“ radiation scientists” (radiation biologist, 48.4%; radiationchemist, 6.3%; radiation physicist, 4.1%; radiation oncolo-gist, 3.1%; and radiation biophysicist, 1.6%). The remaining36.5% of respondents considered themselves to be “cancerbiologists” (cell biologist, 12.5%; molecular biologist,12.5%; physician-scientist, 6.3%; tumor biologist, 3.7%;and biochemist, 1.5%).

The data were further analyzed in terms of scientificspecialty as a function of the decade in which the highestdegree was obtained. For instructors receiving their highestacademic degree during the 1960s, 12 (85.8%) of 14 re-spondents identified themselves as radiation scientists. Forthose receiving their highest degree during the 1970s, 9(64.3%) of 14 identified themselves as radiation scientists.For those receiving their highest degree during the 1980s, 9(56.2%) of 16 identified themselves as radiation scientists,and for those earning their highest degree during the 1990s,3 (37.5%) of 8 respondents identified themselves as radia-tion scientists.

When asked to rank (from 1 to 5) the priority both they,and their respective departments, gave to radiation biologyeducation of residents, 82% of respondents indicated theygave their teaching responsibilities “high” or “highest” pri-ority compared with 10% who gave teaching a “ low” or“ lowest” priority. Similarly, more than two-thirds of respon-dents (68.7%) believed that their departments also gaveteaching a high/highest priority compared with 12.5% whobelieved their departments gave teaching a low/lowest pri-ority.

In terms of teaching workload (Fig. 2), some 51% ofrespondents reported that they did most or all of the radio-biology teaching of residents themselves. Approximately


Fig. 1. Radiation biology instructor demographics: decade during which respondent’s highest academic degree wasobtained. Nearly one-third of survey respondents—mostly “classical” radiobiologists—were at or near retirement age.

Fig. 2. Breakdown of teaching workload among radiation and cancer biology educators. Slightly more than one-half ofinstructors surveyed did most, or all, of the teaching themselves.


20% indicated that they handled about one-half the totalteaching workload, and another 20% claimed to participatein about one-third of the teaching. The remainder (9.8%)participated by presenting only a few lectures.

Radiation biology instructors also take part in other de-partmental activities that qualify as “ teaching,” althoughperhaps not in the strictest didactic sense. For example, amajority of survey respondents indicated that they haveserved as supervisors for resident research rotations(76.5%), presented departmental research conferences(70.6%), invited outside seminar speakers (62.7%), attended“ journal club” (54.9%), and participated in patient confer-ences or tumor boards (51.0%). Some instructors take res-ident mentoring a step further by providing, for example,individual tutoring (beyond what is presented in class) as ameans of ABR written boards preparation (47.1%), assistingresidents with matters of grantsmanship or manuscript prep-aration (45.1%), and discussing issues of medical or scien-tific ethics (39.2%).

In addition to radiation oncology residents, instructorsoften teach radiation and cancer biology to other studentgroups as well, including graduate students (76.1%); diag-nostic radiology/nuclear medicine residents and fellows(34.8%); medical students (32.6%); radiation therapy stu-dents (28.3%); other oncology residents and fellows(23.9%), and undergraduates (17.4%).

Radiation/cancer biology course contentShown in Fig. 3 is the distribution of instructor responses

to the question “A complete lecture ‘cycle’ in radiationbiology consists of approximately how many contact hourswith radiation oncology residents?” Clearly, the variabilityis sizeable between training programs with respect to the

number of hours of radiation and cancer biology instruction.Although no meaningful “average number of lecture hoursper course” can be obtained given the wide variability, it isclear nevertheless that a large majority of programs (ap-proximately 90%) devote at least 21 contact hours annuallyto biology instruction. Furthermore, a full three-quarters ofthese courses are organized “ intradepartmentally,” andtherefore are not listed as official university course offer-ings.

For most programs (84.8%), this course of instruction iscompleted in one or two semesters, although a few (11.4%)spread the teaching load across more than one school year(e.g., consecutive fall or spring semesters, alternating years,and so on), and one or two programs (3.8%) complete theircourse in �3 months. Thus, during a typical four-yearresidency, most radiation oncology residents (approximate-ly 85%) would have at least two opportunities to attend theentire radiation and cancer biology course.

In terms of course format, although didactic lecturespredominate, most are accompanied by, or supplementedwith, problem-solving sessions (79%), visiting seminarspeakers (46%), written examination preparatory sessions(42%), and in-house research conferences (38%). Onlyabout 18% of programs reported that their course consistedsolely of didactic lectures.

A variety of teaching aides are used by radiation biologyinstructors. Nearly all instructors (94.1%) use, and recom-mend that residents purchase, Eric Hall’s textbook Radio-biology for the Radiologist, 5th edition (6). Other teachingaides include custom lecture notes and handouts (80.4%);journal review articles (72.5%); commercially available ra-diobiology practice examinations (7) (66.7%); contempo-rary “ journal club” articles (49%); ASTRO refresher course

Fig. 3. Distribution of total number of resident contact hours in radiation and cancer biology across U.S. radiationoncology training programs, with highly variable results from program to program.


materials (41.2%); historical publications (39.2%); and“other textbooks” (19.9%). The most frequently cited “othertextbooks” included Tannock and Hill’s The Basic Scienceof Oncology, 3rd edition (8) (39.2%), Steele’s Basic Clini-cal Radiobiology, 2nd edition (9) (19.6%), Committee onthe Biological Effects of Ionizing Radiation (10) and UnitedNations Scientific Committee on the Effects of AtomicRadiation (11) reports (19.6%), and Tubiana’s Introductionto Radiobiology (12) (11.8%).

Radiobiology instructors were then presented with ex-haustive lists of possible lecture topics (culled from theABR’s guidelines) grouped into categories of “classicalradiobiology,” “ clinical radiobiology,” and “molecular on-cology” and asked to indicate which lecture topics theyincluded in their own courses. Table 2 lists those lecturetopics that tended to be under-represented among the train-ing programs polled (i.e., topics covered by �60% of pro-grams). Most of the under-represented topics were from the“clinical radiobiology” category, such as the biologic un-derpinnings of brachytherapy, stereotactic therapy, intraop-

erative therapy, and biologic models of retreatment toler-ance. A couple of molecular oncology topics—gene therapyand radiation-induced changes in gene expression—werealso slightly under-represented.

Instructors were also asked to indicate approximatelywhat percentage of their total course was spent on the“categories” of classic radiobiology, clinical radiobiol-ogy, and molecular oncology. The results are indicated,respectively, in Figs. 4 to 6. As was the case for the totalnumber of contact hours per course (Fig. 3), these resultsare also rather variable, although a few generalizationscan be made. Nearly two-thirds (61.2%) of instructorssurveyed indicated that they devoted between 41% and60% of their total course time to classic radiobiology(Fig. 4), although a few other training programs devotedsubstantially less time, and some, substantially more time(less than about 30% of course in classic radiobiology,4% of respondents; �70% of course in classic radiobi-ology, 18.4% of respondents). For clinical radiobiology(Fig. 5), another two-thirds of instructors (63.3%) indi-

Fig. 4. Percentage of existing radiation/cancer biology courses devoted to topics considered “classic radiobiology.”Although percentiles varied considerably, on average, about 50% of the course was composed of classic radiobiologytopics.

Table 2. Under-represented lecture topics in radiation and cancer biology

Radiation or cancer biology lecture topic “Category”

Training programscovering particular

topic (%)

Clinical hyperthermia Clinical 56.9Radiation-induced changes in gene expression Molecular Oncology 51.0Molecular and gene therapies Molecular Oncology 48.9Cancer epidemiology Clinical 41.2Immuno- and radio-labeled antibody therapy Clinical 37.3Radiation histopathology Clinical 35.3Biologic basis of brachytherapy, stereotactic,

and intraoperative therapies Clinical 31.3Models for retreatment tolerance Clinical 31.3Photodynamic therapy Clinical 29.4


cated that they devoted between 21% and 40% of theirtotal course time to this topic area. A few programsdevoted noticeably less time than this (less than about10% of course in clinical radiobiology, 8.2%), and atleast one program devoted much more time than this(greater than about 80% of the course in clinical radio-biology, 2.0%). Finally, 59.1% of programs surveyedindicated that they spent between 11% and 30% of theirtotal course time on molecular and cancer biology (Fig.6), 14.3% spent �10% of their effort on this topic area,and 26.5% spent �30% of their time on this subjectmatter.

Next, survey respondents were asked to indicate whichportion of the radiation and cancer biology curriculum (clas-sic, clinical, or molecular oncology) they were “most com-fortable” teaching. A total of 51.9% of respondents indi-cated their preference for teaching classic radiobiology,

29.6% indicated molecular oncology, and 18.5% stated apreference for clinical radiation biology.

Finally, radiation and cancer biology instructors wereasked what they considered their goals to be with respect tothe education of radiation oncology residents. Clearly, themost immediate and pragmatic goal was to have residentspass their ABR written board examination (indicated bysome 96% of survey respondents). Other, perhaps longerterm, goals included “ raising the consciousness” amongjunior physicians of the role that radiation and cancer biol-ogy play in the day-to-day clinical practice of radiationoncology (85.7%), developing the skills necessary to under-stand, if not take part in, translational research (71.4%), andgaining both the knowledge base and critical thinking skillsrequired to understand a research publication or presenta-tion (65.3%). Finally, some training programs place specialemphasis on preparing a future generation of academic

Fig. 5. Percentage of existing radiation/cancer biology courses devoted to topics considered “clinical radiobiology.”Although percentiles varied, on average, about 30% of the course was composed of clinical radiobiology topics.

Fig. 6. Percentage of existing radiation/cancer biology courses devoted to topics considered “molecular oncology.”Although percentiles varied, on average, about 20% of the course was composed of molecular and cancer biology topics.


radiation oncologists (61.2%) and/or “physician-scientists”(32.7%).

Instructor feedback and satisfactionBetween 40% and 50% of radiation and cancer biology

instructors—a sizeable minority—reported that they contin-ued to be dissatisfied with the feedback they receive aboutwhat they should be teaching (course content and depth) andhow well their residents perform on standardized tests ad-ministered by the ACR and ABR.

Approximately 10% of instructors reported that theyhave no reliable source of information or feedback forcurriculum planning purposes. Most, 75%, of surveyrespondents indicated that they based their curriculumplanning equally on feedback from residents who hadrecently sat for the ABR written board examination, andon their own years of teaching experience, that is, theirinnate “ sense” of what residents do or do not need toknow about radiation and cancer biology. Other sourcesof feedback for course content included (in descendingorder): (1) the commercially available radiobiology prac-tice exam (7) (last updated in 1999), 56.2% of totalresponses; (2) the “official” ABR guidelines, 47.9%; (3)existing radiation and/or cancer biology textbooks,43.8%; and (4) information obtained from clinical facultymembers, 33.3%. Approximately 41.3% of instructorssurveyed believed that overall, the feedback they didreceive was inadequate for curriculum planning pur-poses.

In terms of resident performance on standardized exams,

most instructors received feedback from either other mem-bers of the faculty (e.g., residency program director, depart-ment chair and/or discussed at faculty meetings; 72.7%) orthe residents themselves (25.8%). The remaining surveyrespondents (1.5%) indicated that they received no feedbackwhatsoever. The feedback that was received consisted ofwhether the residents passed the radiation biology portion ofthe exam (56.2% of total responses received), the exam as awhole (54.2% of total responses), and the resident’s percen-tile ranking in radiobiology (47.9% of total responses).Some 47.5% of instructors surveyed believed that, overall,what feedback they did receive was insufficient to gaugeresident performance in radiation and cancer biologyadequately.

Despite the perceived problems with feedback, mostinstructors (89.6%) indicated nevertheless that they up-dated their teaching materials at least annually, if notmore frequently, as pertinent, new information becameavailable.

Respondents were offered a list of choices that couldhelp alleviate feedback problems. They were asked torank them from 1 to 5 in order of perceived importance,with a ranking of 1 or 2 deemed “very important/impor-tant” and a ranking of 4 or 5 considered “ less important/unimportant” (a ranking of 3 was viewed as “neutral” ).As shown in Table 3, the top three choices in order ofperceived importance were (1) providing a breakdown ofresidents’ scores on the radiobiology portion of standard-ized exams into subcategories (e.g., classic, clinical, ormolecular oncology; 74.2% considered “very important/

Table 3. Factors perceived by instructors as important sources of feedback for curriculum planning and evaluatingresident performance in radiation and cancer biology

Remedial factor

Veryimportant/important

(%)Neutral

(%)

Lessimportant/unimportant

(%)

Breakdown of residents’ scores on thebiology portion of the ABR writtenexamination into subcategories 74.2 6.5 19.3

Instructor access to sample writtenexamination questions 67.5 5.5 27.0

Easier instructor access to ABR’sguidelines/syllabus for radiation andcancer biology education 60.0 17.1 22.9

Instructor access to a breakdown ofexamination questions bysubcategory 58.3 25.0 16.7

Access to both raw and normalizedwritten exam scores 51.3 27.0 21.6

More information as to how thewritten exam are composed andgraded 48.6 29.7 21.6

Abbreviation: ABR � American Board of Radiology.


important” ); (2) maintaining access to sample exam ques-tions in radiation and cancer biology (67.5% considered“very important/important” ); and (3) ensuring instructoraccess to the ABR “Radiation Oncology Resident Train-ing Guidelines for Cancer and Radiation Biology” (4)(60% considered “very important/important” ). Thosechoices deemed neutral, less important, or unimportantincluded (1) providing a breakdown of the radiobiologyquestions on recent written exams into subcategories; (2)instructor access to both raw and normalized exam scoresfor residents in their programs; and (3) receiving moreinformation as to the process of how the written examsare composed and graded.

DISCUSSION

The major findings of the radiation biology teachingsurvey conducted in early 2001 can be summarized asfollows:

1. Workforce: The supply of instructors qualified to teachclassical radiobiology to radiation oncology residents isdwindling. Many classically trained radiation biologistsare currently at, or near, retirement age and the youngerscientists who have entered the teaching workforce dur-ing the past decade may have little, if any, formal train-ing in the radiation sciences. As of the time of the survey,approximately 40% of all instructors charged with teach-ing radiobiology to residents did not hold a degree in aradiation science (although they were obviously well-versed in molecular and cancer biology). Furthermore, inslightly more than one-half of the training programspolled, a single instructor handled most, or all, of theteaching load.

2. Curriculum: The percentage of total teaching time de-voted to classic, clinical, and molecular radiation biologymatches the percentages of questions on these subjectson the ABR Written Boards (13). Nevertheless, the vari-ability is large between radiation oncology training pro-grams with respect to the total number of contact hoursper complete radiobiology course, ranging from as fewas approximately 10 to �50 hours. In addition, a numberof lecture topics—particularly in clinical radiobiology—are covered by �60% of training programs. This may bebecause of existing instructors’ perceived “discomfort”with teaching clinically oriented subject matter.

3. Instructor feedback: A sizeable minority (40–50%) ofbiology teachers remain dissatisfied with the feedbackthey receive with respect to both curriculum content anddepth and the performance of their residents on standard-ized radiobiology examinations administered by theACR and/or the ABR. When offered a number of choicesdesigned to help alleviate the feedback problems, in-structors listed, in order of perceived importance: pro-viding a breakdown of residents’ scores on the radiobi-ology portion of standardized exams into subcategories;maintaining access to sample exam questions in radia-

tion and cancer biology; and ensuring instructor access tothe ABR Guidelines for Resident Education in RadiationOncology.

Other activities of the ASTRO Joint Working Group onRadiobiology Teaching have included participation in a sym-posium titled “Teaching Radiobiology in the New Millen-nium” held at the 42nd Annual Meeting of ASTRO, October2000, and a refresher course titled “Toward a Consensus onRadiobiology Teaching of Radiation Oncology Residents”held at the 48th Annual Meeting of RRS, April 2001. Theseactivities were intended to heighten awareness of some of theissues facing radiation and cancer biology educators today, andtargeted both the clinical (ASTRO) and the research (RRS)communities. These sessions were both well-attended andhighly rated. A “companion” report to this one was recentlypublished in the journal Radiation Research (13) and providesa more comprehensive account of the presentations made at theASTRO and RRS sessions.

The creation of the biology teacher’ s electronic mail-ing list provides a forum for radiation and cancer biologyteachers to communicate better with each other, dissem-inate important information with respect to curriculumcontent, and share teaching resources. Those teachersinterested in using this resource should contact the AS-TRO main office. A number of Web-based educationalresources are currently under consideration as well in thisregard (see also below).

An ASTRO School of Radiation Oncology continuingmedical education meeting was held in August 2001, titled“A Course for Residents, Radiation Oncologists and Radio-biologists in Cellular and Molecular Biology.” The purposeof this course was to inform radiation and cancer biologyeducators, practicing radiation oncologists, and residents ofnew developments in molecular oncology and how theseintegrate within the framework of classical and clinicalradiobiology. Among the topics discussed were the roles ofoncogenes and tumor suppressor genes in tumor response totherapy, radiation and hypoxia-induced changes in geneexpression, and angiogenesis and vascular targeting strate-gies for therapeutic benefit. Approximately 70 people at-tended the meeting—largely a mix of residents and educa-tors—and most were quite satisfied with their experienceand looking forward to more ASTRO-sponsored meetingsof this kind. The success of the workshop bodes well for thefuture of similar meetings.

Furthermore, the RRS devoted two, one-hour refreshercourses at its 49th Annual Meeting in April 2002 to“Classical Radiobiology: A Primer for Resident Teach-ing.” The subject matter for the 2002 courses was thehistory of survival curves, survival curve theory and models,and the effects of dose modifying agents on survival curveshape. Should this initiative be deemed successful, more ses-sions such as this, geared toward younger investigators withlittle or no radiation biology background, may be considered inthe future. Such activities, whether sponsored by the RRS or


ASTRO (or both), may be helpful in addressing the dwindlingworkforce issue.

The Joint Working Group on Radiobiology Teachingcontinues to maintain an open dialog with the ACR, ABR,RRC, and SCAROP with respect to matters of manpower,radiobiology curriculum standardization, and instructorfeedback as to resident performance on the annual ACRin-training and ABR written board exams. In direct responseto the suggestions of biology educators, easier access (andtimely updates) to the ABR’s “Radiation Oncology Resi-dent Training Guidelines for Cancer and Radiation Biol-ogy” (4) can be obtained at http://www.theabr.org/1_Onco-BasicSci.htm. An effort will be made to provide moresubcategorized information on scores on the radiobiologyportion of the standardized tests. Furthermore, a significanteffort is currently underway to expand and better “modern-ize” the radiation and cancer biology content of the annualACR in-training examination, through the formation of aquestion-writing subcommittee composed of both radiationand cancer biologists with different areas of expertise. Theinitial efforts of this subcommittee were reflected in ques-tions included on the March 2002 in-training exam. Com-pared with previous years, the exam had a somewhat greateremphasis on the molecular aspects of radiation and cancerbiology, as well as on recent advances and research find-ings. Questions were also included on topics that the surveyidentified as “under-represented” (Table 2), in an effort tocorrect these deficiencies. The distribution of questionsdealing with the fundamentals of radiation biology versusmolecular oncology did not change appreciably for the 2002examinations. However, it is anticipated that in future years,a greater shift in this balance away from classical radiobi-ology will occur.

Finally, a subcommittee of the Joint Working Group onRadiobiology Teaching, chaired by Dr. Barry Rosenstein(Table 1), will be working to develop a more detailedcore curriculum for radiation and cancer biology thatcould be useful for educators, and be “adoptable” by theABR, ACR, RRC, and SCAROP. Detailed information asto a specific curriculum, references to relevant papers andreview articles, and other teaching materials and toolswill be provided as part of a Web site that is beingdeveloped for this purpose. This should also allow in-structors to gain a better sense of the kinds of topics thatwill be emphasized on future standardized tests. Thissubcommittee faces a difficult challenge in trying toachieve an appropriate balance between classical andclinical radiobiology versus cancer and molecular oncol-ogy. It is also anticipated that the subcommittee willaddress whether a minimal number of contact-hours incancer/radiobiology should be established; this may alsoprove to be a problematic and contentious issue given thewide variability that exists currently between residencytraining programs, not to mention the growing manpowershortage.

Several additional findings of the survey deserve men-tion. One surprising finding was the apparent discomfortof many existing radiation and cancer biology instructorsin teaching the more clinically oriented aspects of radi-ation and cancer biology. Thus, it may not be so surpris-ing that selected lecture topics in clinical radiobiologytend to be those most under-represented in radiobiologycurricula across the United States (Table 2). Surely, thisproblem will likewise worsen over time as classical ra-diobiologists continue to be replaced by cancer and mo-lecular biologists who already have little or no training inthe radiation sciences, let alone in the clinical aspects ofradiation oncology. Also surprising was the finding thatonly a minority (albeit a large one) of educators claim tobe dissatisfied with the feedback they receive with re-spect to curriculum planning and resident performance onstandardized tests. On the basis of audience commentsand feedback culled from the teaching symposia held atrecent ASTRO and RRS meetings, the level of dissatis-faction was anticipated to be higher than actually re-ported. It is possible therefore that the approximately40% of nonresponders to the survey may represent themost “disgruntled” group of all. If so, this might also callinto question the validity of the survey findings indicat-ing that most instructors, and departments, give highpriority to radiation biology education of residents. Fi-nally, it is worth noting that although the overwhelmingmajority of educators depend on, and recommend thattheir residents purchase, Dr. Eric Hall’ s seminal textbookRadiobiology for the Radiologist (6), several other teach-ing resources (custom lecture notes, review articles, othertexts) are also in common use. It is indeed a testament toDr. Hall’ s contribution to the field of radiation oncologythat, historically, reliance on his textbook alone has beensufficient for most residents to pass the radiobiologyportion of their ABR written board examination. How-ever, with cancer and molecular biology expected to befeatured more prominently on standardized tests in thefuture, it may be time to reevaluate the various teachingresources used for cancer and radiobiology education.

The Joint Working Group on Radiobiology Teaching hasas its future goals to better define the nature and scope ofthese issues, possibly through the use of additional surveys,and to then make recommendations accordingly. For exam-ple, more work needs to be done to better clarify whetherthose instructors who do not consider themselves radiationscientists have, in fact, ever taken a radiation biology course. Ifso, they may be sufficiently qualified to teach radiation biologyto residents, even though they do not necessarily identifythemselves as radiation scientists per se.

Readers are encouraged to contact members of the Biol-ogy Teachers Working Group with any comments, criti-cisms, and other suggestions they may have or to becomefurther involved in matters related to radiation and cancerbiology education.


REFERENCES

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2. Coleman CN, Griffin TW, Prosnitz LR, et al. Training theradiation oncologist for the twenty-first century. Int J RadiatOncol Biol Phys 1996;35:821–826.

3. Radiation Oncology Resident Training Working Group andthe Members of SCAROP. Radiation oncology training inthe United States: Report from the Radiation OncologyResident Training Working Group organized by the Societyof Chairman of Academic Radiation Oncology Programs(SCAROP). Int J Radiat Oncol Biol Phys 1999;45:153–161.

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9. Steel GG. Basic clinical radiobiology. 2nd ed. New York:Oxford University Press; 1997.

10. Committee on the Biological Effects of Ionizing Radia-tions. Health effects of exposure to low levels of ionizingradiation, BEIR V. Washington, DC: National AcademyPress; 1990.

11. United Nations Scientific Committee on the Effects ofAtomic Radiation (UNSCEAR). Sources and effects ofionizing radiation. Vienna: United Nations Publications;1993.

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13. Dynlacht JR, Dewhirst MW, Hall EJ, et al. Toward a consen-sus on radiobiology teaching to radiation oncology residents.Radiat Res 2002;157:599–606.


Toward a national consensus: teaching radiobiology to radiation oncology residents

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