Approach to mammogram

Approach to mammogram

General breast anatomy• Conical, round or hemispherical shape

• Comprised of 15-20 lobes, each encased in fascial sheath defined by AMF & PMF

• Extends from 2nd or 3rd intercostal space to 6th or 7th intercostal space• Extends laterally to anterior axillary fold and medially to lateral sternum

• Relationship to chest wall• Superior two-thirds overlies pectoralis major muscle• Lateral portions overly serratus anterior muscle• Inferior-most margin overlies upper abdominaloblique muscles

• Axillary tail of Spence: Extension of normal breast• tissue toward axilla

ZONAL ANATOMY

• Premammary (Subcutaneous) Zone• Most superficial zone• Anterior margin defined by skin, posterior margin defined

by AMF• Contains subcutaneous fat, blood vessels,

anteriorsuspensory (Cooper) ligaments• May contain ectopic ducts and TDLUs ASLs(Cooper

ligaments)• Formed from two leaflets of AMF inserting into dermis• Provide support for breast• Usually visible on mammograms and sonograms

• Mammary Zone• Defined anteriorly by AMF and posteriorly by PMF• Contains majority of ducts/TDLUs, stromal fat and

stromal connective tissue• Subdivided haphazardly by interspersed ASLs.

• Retromammary Zone• Most posterior of three zones• Defined anteriorly by PMF and posteriorly by chest wall• Contains fat and PSLs which attach PMF to chest wall

BI-RADS BREAST COMPOSITION

• The American College of Radiology Breast Imaging and Reporting Database System (BI-RADS)divides breast composition into four categories:

• 1) almost entirely fat,• 2) scattered fibroglandular densities

(approximately 25-50% glandular),• 3) heterogeneously dense (51-75% glandular),• 4) extremely dense (greater than 75% glandular).

BIRADS CATEGORIES

BIRADS INFERENCE RISK OF MALIG.

TYPICAL EXAMPLES

0 Needs additional imaging evaluation

1 Negative/ Normal2 Benign Findings.

No further evaluation needed

•Fat containing.•Benign Intramammary LN•Benign Calcifications

3 Probably Benign.

Short term Follow up is suggested

=< 2 % Round, oval or lobulated lesion with circumscribed margins.

4 Suspicious Abnormality.

Biopsy should be considered

3 – 94 %

5 Highly suggestive of malignancy

Appropriate intervention to be taken

> 95% Irregular shaped, spiculated margins.

6 Biopsy proven Malignancy

BIRADS MAMMOGRAPHY

LEXICON

MASS CALCIFICATION ASYMMETRIC BREAST FINDINGS

INTRAMAMMARYLYMPHNODE

TUBULAR DENSITY

ARCHITECTURAL DISTORTION

OTHER ASSOCIATED

FINDINGS



TUBULAR DENSITY


OTHER ASSOCIATED

FINDINGS

SOL seen in two different projections and have convex borders.

1. SIZE

2. SHAPE

3. MARGINS

5. CALCIFICATION

4. DENSITY

SHAPE

MARGINS

High Iso Low ( not fat) Fat containing

Oil cystsLipomaGalactoceleHamartomasFibroadenolipomas

DENSITY


INTRAMAMMARYLYMPH NODE

TUBULAR DENSITY


OTHER ASSOCIATED

FINDINGS

Morphology

Distribution

Number

Size

MORPHOLOGY

BENIGN

INTERMEDIATE CONCERN OR SUSPICIOUS

CALCIFICATION

HIGH PROBABILITY OF MALIGNANCY

Skin CalcificationVascular CalcificationPopcorn CalcificationRod like CalcificationLucent Centered DepositsEggshell/ Rim CalcificationPrecipitated Calcification in milk of calcium.Large Dystrophic Calcification

MORPHOLOGY: Benign

Skin CalcificationTattoo SignUsually located along

inframammary fold parasternally, axilla and areola.

Can be seen in the skin which is enface

Vascular Calcification

Linear or parallel tracks that are usually clearly associated with blood vessels.

Popcorn Calcification

Involuting Fibroadenoma

Rod like calcificationWithin ectatic ducts due

to secretory deposits and follow ductal distribution radiating towards nipple.

May be continuous or discontinuous and may show branching.

Differentiate from malignant fine branching calcifications.

Lucent centered deposits

Fat NecrosisCalcified Debris in

ductsOccasionally in

Fibroadenoms

Eggshell or Rim Calcification

Wall of the Cyst.Fat Necrosis.Periphery of Fibroadenoma

Milk of CalciumAre benign sedimented

calcification in macro or micro cysts.

Typical feature is apparent change in shape on different projections.

• Whenever there is possibility of milk of calcium consider magnification medio-lateral spot film

Dystrophic Calcification

Coarse irregular lava shaped calcification.

In irradiated breast or following trauma

Round calcification

>0.5 mm.In fibrocystic changes

or adenosis or skin calcification.

MALIGNANCYOF RISK

MORPHOLOGY: Intermediate Concern

Amorphous or indistict calcification Calcification without a clearly

defined shape or form. They are usually so small or hazy in appearance, that a more specific morphologic classification can not be determined.

Present in many benign and malignant breast diseases. About 20% of amorphous calcifications turns out to be malignant.

Coarse Heterogenous

Irregular calcification that are usually larger than 0.5 mm but not the size of large heterogenous dystrophic calcifications.

Fine Pleomorphic:< 0.5 mmVariable in size,

density or form25 – 40% risk of

malignancy

MORPHOLOGY: High Probability of Malignancy

Fine Linear or Branching

< 0.5mm in width.

Linear or branching distribution

• As compared to Malignant Calcification, Benign Calcifications are: – Larger– Coarser– Round and smooth– Easily seen.



TUBULAR DENSITY


OTHER ASSOCIATED

FINDINGS

• In contrast to a mass, which is a 3-D structure demonstrating convex outward borders and which is usually evident on two orthogonal views, asymmetric findings lack the convex outward borders and the conspicuity typical of a mass.

ASYMMETRIC BREAST

FINDINGS

ASYMMETRY GLOBAL ASYMMETRY

FOCAL ASYMMETRY

• If a potential mass is seen in only a single view at standard mammography, it should be called an “asymmetry” until its three-dimensionality is confirmed.

• Approximately 80% of cases are due to summation shadow, of normal fibroglandular breast.

• True lesions may sometimes appear on only one view because on other views they are either obscured by overlapping dense parenchyma or are located outside the field of view.

ASYMMETRY

• Is seen in both the views.• Involves a greater volume of breast tissue (at least a

quadrant)• Without any associated mass, suspicious

calcifications, or architectural distortions.• It is usually due to normal variations or hormonal

influence and only significant when it corresponds to a palpable abnormality.

GLOBAL ASYMMETRY

• Is seen in both the views.• Involves a less than one quadrant of breast.• It can be due to normal variations or some lesion.

FOCAL ASYMMETRY

DEVELOPING ASYMMETRY

• This is a focal asymmetry that is new, larger, or denser at current examination than at previous examinations.

ASYMMETRY BIRADS I

DEVELOPING ASYMMETRY BIRADS IV

NON- PALPABLE

GLOBAL ASYMMETRY BIRADS II

NON-PALPABLE

FOCAL ASYMMETRY BIRADS III

PALPABLE GLOBAL ASYMMETRY BIRADS IV

PALPABLE FOCAL ASYMMETRY BIRADS IV

MASS CALCIFICATION

ASYMMETRIC BREAST

FINDINGS

INTRAMAMMARY

LYMPHNODE

TUBULAR DENSITY


OTHER ASSOCIATED

FINDINGS

• Well circumscribed.• < 1cm• UPPER AND OUTER

QUADRANT• Lucent and invaginated

fatty hilum• May appear as 3 or more

round densities in horse shoe arrangement.

BENIGN INTRAMAMMARY LYMPH NODE

• If a mass is seen in a section other than upper and outer quadrant, unless it has a clearly defined hilum.

• Lesion in upper outer quadrant does not have other characteristics, it should be considered suspicious as malignant node or primary mass.

When not to consider Benign Intramammary node



TUBULAR DENSITY


OTHER ASSOCIATED

FINDINGS

• Tubular or branching structure representing dilated duct.

• Usually of minor significance.

• BIRADS III



TUBULAR DENSITY


OTHER ASSOCIATED

FINDINGS

• Spiculations radiating from a point without any identifiable mass.

• The only architectural distortion that does not require further evaluation is that caused by prior surgery or trauma.

• BIRADS IV

SKIN RETRACTION

NIPPLE RETRACTION

SKIN THICKENING

TRABECULAR THICKENING

AXILLARY LYMPHADENOPATHY

• FINALLY WE HAVE to decide on the significance of the mammographic findings.

• FINALISE THE REPORT IN 7 SPECIFIC CATEGORIES.

Approach to mammogram

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