Carcinoma rectum

CARCINOMA RECTUM

DR.BARUN KUMAR

MS GENERAL SURGERY

SSKM & IPGMER

INCIDENCE

• Currently third leading cause of death in US in both gender

• 41000 new cases diagnosed in US each year and 10000 deaths attributed to rectal carcinoma

• Incidence rate in India is quite low about 2 to 8per 100,000

• Median age- 7th decade but can occur any time in adulthood

Etiology and risk factors

• The lifetime risk of colorectal carcinoma is 6% in western population

1. Family history in first degree relative

i) FAP

ii) HNPCC

2. Inflammatory bowel disease

i) ulcerative colitis: 25% risk in 25 years

ii) crohn’s disease

Etiology and risk factors

3. Dietary fats –

• red meat fats

• 20% of diet as fat

4.Synergistic effect of alcohol and smoking with increased risk

Adenoma to carcinoma sequence

• First described by DUKES in 1926

• The time course is 5-10 years

• Non inherited cases has ras, p53 mutations

• Malignant potential –

villous adenoma

Diameter >2cm

.

Diagnosis

• HISTORY

Symptoms : bleeding p/r , change in bowel habit (fixed mass), pain in defecation (sphincter)

Constitutional symptoms

Family history

Relevant medical conditions

Diagnosis

PHYSICAL EXAMINATION

• DRE : size, mobility, fixation, location, distance from anal verge, relationship with anal sphincter

• RIGID PROCTOSCOPY : distance from anal verge, circumferential involvement , orientation, relationship with surrounding structures

Diagnosis

PHYSICAL EXAMINATION

• COMPLETE COLONOSCOPY : synchronous growth in 2-8%

• Pelvic examination in females and prostate examination in males

AJCC 7th edition staging for colorectal ca




Preoperative staging

• Abdominal and pelvic CT scan:

sensitivity

• for distant metastasis (75-87%)

• for perirectal nodal involvement (45%)

specifity considered close to 100%

• depth of transmural invasion (70%)

iv contrast for assessment of liver mets and ureteral involvement


• Endoluminal ultrasound :

Accuracy of 80-95% for T staging

Instrumental in assessing T1 & T2 lesions

Con: intra-observer difference, understage the tumor



uT1 Invasion confined to mucosa and submucosa

uT2 Penetration of muscularis propria but not through to the mesorectal fat

uT3 Invasion into the perirectal fat

uT4 Invasion into the adjacent organ

uN0 No enlargement of lymph nodes

uN1 Perirectal lymph node enlarged

ENDOSCOPIC ULTRASOUND STAGING OF RECTAL TUMORS


• ENDORECTAL COIL MRI :

Larger field of view

less operator dependent

Assessment of stenotic tumor

Identification of perirectal nodes (accuracy of 95%)

Identification of sphincter involvement (100%)


• PET

For assessing the pathological response of primary tumor to pre-op chemoradiation

Metastasis in brain and bones


• CEA (carcinoembryonic antigen )

Baseline CEA preoperatively for

staging,

assessment of prognosis (>5ng/ml worse prognosis)

Presence of persistence disease after resection

GOAL OF SURGERY

• PRIMARY GOAL IS ERADICATION OF PRIMARY TUMOR ALONG WITH ADJACENT MESORECTAL TISSUE AND SUPERIOR HEMORRHOIDAL ARTERY PEDICLE

RESECTION MARGIN

• Traditional margin of 5cm

• NSABP demonstrated no difference in survival or local recurrence in distal margin of 2, 2-2.9, >3cm

• Therefore, 2cm distal margin Is now acceptable considering the limitation of distal intramural spread of 2cm below the peritoneal reflection

RESECTION MARGIN

• Circumferential radial margin is more crucial

• Length of mesorectum removed beyond the primary tumor is between 3 to 5 cm as tumor implants have not been shown further than 4cm

LOCAL EXCISION

• Provide adequate oncological control with significantly less morbidity than APR in a subset of patients.

LOCAL EXCISION

Tumors amenable to local excision

• T1N0 or T2N0 lesion

• <4cm in diameter

• <40% in circumference of lumen

• <10 cm from dentate line

• Well to moderately differentiated histology

• No evidence of lymphatic or vascular invasion

• Local control for advanced disease

LOCAL EXCISION

TECHNIQUES:

Transsphincteric excision

Transanal excision

Transcoccygeal excision

Transanal endoscopic microsurgery

LOCAL EXCISION

TRANSANAL EXCISION

• Tumors 6-8 cm from anal verge

• 1 cm circumferential margin

• Full thickness excision

LOCAL EXCISION TRANSANAL EXCISION

LOCAL EXCISION

TRANSCOCCYGEAL EXCISION

• Popularized by KRASKE

• Useful for more proximally placed, posterior lesions

• 1 cm circumferential margin

• Complication: fecal fistula ( 5 to 20%)

LOCAL EXCISION

TRANSCOCCYGEAL EXCISION

LOCAL EXCISION

• TRANSANAL ENOSCOPIC MICROSURGERY

• the procedure of choice for early mid to upper rectal lesion

• Offers better visualization, complete intact excision

LOCAL EXCISION

LOW ANTERIOR RESECTION WITH TME

• local failures are most often due to inadequate surgicalclearance of radial margins.

• conventional resection violates the mesorectalcircumference during blunt dissection, leaving residualmesorectum.

• TME involves precise dissection and removal of the entirerectal mesentery as an intact unit.

• local recurrence with conventional surgery averagesapprox. 25-30% vs. TME 4-7% by several groups (althoughseveral series have higher recurrence)


PROCEDURE :

A. MOBILIZATION OF COLON

B. TRANSECTION

C. RECONSTRUCTION

Double stapling technique

• Diverting loop ileostomy

• Colonic pouch/ transverse coloplasty



Specific complications

• Impotence (10-28%)

• Retrograde ejaculations

• Urinary incontinence


TME ALONE (%) TME+RT (%) TME +LND (%)

LOCAL RECURRENCE

12.1 5.8 6.9

LATERAL PELVIC RECURRENCE

2.7 0.8 2.2

PRESACRAL RECURRENCE

3.2 3.7 0.6

ABDOMINOPERINEAL DISSECTION

Suitable for

• Cancers involving the sphincter apparatus

• Incontinent to feces

Very High morbidity (61%)

Mortality 0 to (6.3%)


Complications:

• Perineal wound complications (25%)

• Urinary incontinence (as high as 50%)

• Sexual dysfunction (as high as 67%)

• Stoma complications

(ischemia, retraction, hernia, stenosis , prolapse)


En block excision :

• Posterior vaginectomy ( 1cm margin)

• prostatectomy

• Pelvic exenteration

( high morbidity and mortality )

Consider prophylactic bilateral oopherectomy

CHEMORADIATION

ADVANTAGES OF NEOADJUVANT CHEMOTHERAPY

• Downstage the tumor (60-80%)

• Achieve complete pathological response (15-30%)

• To allow sphincter preserving procedures

• No radiation to anastomosis, small bowel in pelvis

CHEMORADIATION

• 1990 NIH consensus concluded the efficacy in local control in stage II & III

• To lower local failure rates and improve survival in resectable cancers

• to allow surgery in primarily inoperable cancers

• to facilitate a sphincter-preserving procedure

• to cure patients without surgery: very small cancer or very high surgical risk

5Fu

Leucovorin

Oxaliplatin

Irinotecan

Bevacizumab

cetuximab

Combinations FOLFOX

FOLFIRI

Leucovorin/5FU

Capecitabine

Bevacizumab in combination with the above regimens.

Chemotherapy agents

CHEMORADIATION

Pre-op RT vs. surgery alone

Swedish Rectal Cancer Trial (NEJM 1997;336:980 ): 1168 patients

randomised to 25 Gy (5x5) PRT or no RT.

Surgery alone Preop. RT

Rate of local recurrence 27% 11% p<0.001

5-year overall survival 48% 58% p=0.004

Dutch Colorectal Cancer Group (Kapiteijn E. NEJM

2001;345:638): 1861 patients randomised TME vs PRT+TME

TME PRT+TME

Recurrence rate 8.2% 2.4%

OS ns ns

Pre-op vs. post-op Chemo RT

Randomized trial of the German Rectal Cancer study

Group (Sauer R et al. N Engl J Med 2004;351:1731-40):

Preop CRT Postop CRT

Patients N=415 N=384

5 y. OS 76% 74% p=0.8

5 y. local relapse 6% 13% p=0.006

G3,4 toxic effects 27% 40% p=0.001

• Increase in sphincter-preserving surgery with preop Th.

• No difference in overall survival or disease free survival at 4 years

Polish Trial

• Polish Study (Br J Surg. 2006): 316 patients with resectable T3-4 rectal cancer, no sphincter involvement, tumor palpable on DRE (1999-2002).

Preop short Preop

course RT conventional

RT

5 y. OS 67.2% 66.2%

5 y. local relapse 9.0% 14.2%

DFS 58.4% 55.6%

NO difference in anorectal or sexual dysfunction

CURRENT RECOMMENDATION

•Primary surgery

•No adjuvant therapy

Stage I


• Neoadjuvant Chemoradiation ( 5-FU based chemotherapy with radiotherapy )

• Rest for 4-8 weeks

• Total mesocolic excision

• Rest for 4 weeks

• Chemotherapy in appropriate patients for 4-6 months

STAGE II or III

low/

midlesion


• Pre or post op chemoradiation

• TME

Stage II or III

High lesion


• Palliative surgery

• Adjuvant chemotherapy

• 5-FU + leucovorin +/- irinotecan or oxaliplatin

STAGE IV

SURVEILLANCE

• Screening for rectal recurrence and metachronous colorectal neoplasm

• 60- 80% recurrence in 24 months, 90% in 48 months

• Each visit DRE+ sigmoidoscopy + CEA

• CT scan : 1 year postresection and then annually till 3 years

SURVEILLANCE

• Postoperative at 2 weeks and then every 3 months for 2 years

• After 2 years every 6 months for 5 years

• If no recurrence, then colonoscopy every 3-5 years

• Close observation for high risk patients

REFERENCES

1. Maingots’s abdominal operations 12th ed

2. ACS surgery7 , 2014 ed

3. Sabiston’s textbook of surgery, 18th ed

4. NCCN practical guidelines in oncology v.2.2009

5. Practice Parameters for the Management of RectalCancer (Revised)

J. R. T. Monson, M.D. • M. R. Weiser, M.D. • W. D. Buie, M.D. • G. J. Chang, M.D.

J. F. Rafferty, M.D.; Prepared by the Standards Practice Task Force of the American Society of Colon and Rectal Surgeons

Thank you

Carcinoma rectum

Health & Medicine

edition staging

preoperative staging

t staging instrumental

colorectal ca ajcc

perirectal nodal involvement

carcinoma sequencefirst

diagnosis history symptoms

perirectal fat ut4invasion