BI-RADS

RMG: NOV,2016. @KIJOHS KIZZA JOHN KIJOHS

BI-RADS®

The Breast Imaging Reporting and Data System® (BI-RADS®) initiative, instituted by the ACR, was begun in the late 1980s to address a lack of standardization and uniformity in mammography practice reporting 2003, first edition of the ACR BI-

RADS lexicon for US introduced BI-RADS® was officially launched in

Uganda on Nov 4, 2016. To be used country-wide.

BI-RADS®

Designed to standardize breast imaging reporting and to reduce confusion in breast imaging interpretations. Facilitates outcome monitoring and quality assessment Contains a lexicon for standardized terminology (descriptors) for

mammography, US and MRI Divided into 6 categories BI-RADS (0,1,2,3,4,5,6)

Category 0 (BI-RADS® 0)

• Assessment is incomplete • Temporary category, usually during screening • Need additional imaging evaluation and / or prior images / results for

compulsion • Patient unable or unwilling to wait for completion of full diagnostic

examination

Category 1 (BI-RADS® 1)

• Negative • This is a normal examination • Routine screening

Category 2 (BI-RADS® 2)

• Benign • Simple cyst, intramammary lymph nodes, postsurgical fluid collection,

breast implants, or complicated cyst / probable fibroadoadenomas that are unchanged for atleast 2 or 3 years

Category 3 (BI-RADS® 3)

• Probably benign • NOT an indeterminate category for use simply when the radiologist is

unsure whether to render a benign (BI-RADS category 2) or suspicious (BI-RADS category 4) assessment

• Reserved for specific imaging findings known to have > 0% but ≤ 2% likelihood of malignancy.

• Fibroadenoma, an isolated complicated cyst, clustered microcysts • Short-interval (6 months) follow-up sonography • Follow up 6m, if stable 6m, if stable 12m, all maintaining the cat 3.

After 2-3yrs of stability, final assessment cat be changed to cat 2

Category 4 (BI-RADS® 4)

• Reserved for findings that do not have the classic appearance of malignancy but are sufficiently suspicious to justify a recommendation for biopsy

• Wide range of likelihood of malignancy, > 2% but < 95% likelihood of malignancy

• Subdivided into 4A, 4B, 4C • The positive predictive value of category 4 mammographically

detected breast abnormalities is between 23% and 34%

Category 5 (BI-RADS® 5)

• Highly suggestive of malignancy • Carry high probability (≥ 95%) of malignancy • Tissue diagnosis • Biopsy should be performed in the absence of clinical

contraindication

Category 6 (BI-RADS® 6)

• Known Biopsy-Proven Malignancy • Imaging performed after percutaneous biopsy but prior to surgical

excision, in which there are no abnormalities other than the known cancer that might need additional evaluation.

BI-RADS® Lexicon

Tissue composition (screening only) Homogeneous background echotexture – fat Homogeneous background echotexture – fibroglandular Heterogeneous background echotexture

NO

RMAL AN

ATOM

Y

ALMO

ST ENTIRELY FAT

HOMOGENEOUS FIBROGLANDULAR HETEROGENEOUS

BI-RADS® Lexicon

Masses Shape i. Oval ii. Round iii. Irregular Orientation i. Parallel ii. Not parallel Margin i. Circumscribed • Not circumscribed (Indistinct, Angular,

Microlobulated, Spiculated)

Echo pattern i. Anechoic ii. Hyperechoic iii. Complex cystic and solid iv. Hypoechoic v. Isoechoic vi. Heterogeneous Posterior feature i. No posterior features ii. Enhancement iii. Shadowing iv. Combined pattern Calcifications Calcifications in a mass Calcifications outside of a mass Intraductal calcifications

BI-RADS® Lexicon

Associated features Architectural distortion Duct changes Skin changes i. Skin thickening ii. Skin retraction Edema Vascularity i. Absent ii. Internal vascularity iii. Vessels in rim Elasticity assessment i. Soft ii. Intermediate iii. Hard

Special cases

Simple cyst Clustered microcysts Complicated cyst

Mass in or on skin Foreign body including implants Lymph nodes – intramammary

Lymph nodes – axillary Vascular abnormalities i. AVMs (arteriovenous malformations/

pseudoaneurysms)

ii. Mondor disease Postsurgical fluid collection Fat necrosis

Shape

ROU

ND

OVAL

IRREGU

LAR IRREG

ULAR

Margins

CIRCUM

SCRIBED N

OT CIRCU

MSCRIBED

NO

T CIRCUM

SCRIBED N

OT CIRCU

MSCRIBED

Echogenicity

ANECHO

IC HYPO

ECHOIC

HYPERECHOIC

COM

PLEX MASS

BIRADS POSITION OF BREAST LUMPS

Simple cysts

• The initial role of diagnostic breast sonography, to distinguish between cysts and solid nodules, remains a key role for sonography

• Simple cysts are as definitively benign

• If strict criteria for a simple cyst are met, the lesion is BIRADS 2

• Complicated and complex cysts create a spectrum of lesions that can be characterized as BIRADS 2, 3, or 4.

Solid nodules

• A solid nodule initially was an automatic indication of biopsy

• Identifying a solid nodule that is so likely to be benign that the patient can be offered the option of follow-up in addition to the option of biopsy.

• BIRADS 3 have a 2% or lower chance of being malignant

Suspicious finding

• The morphologic features of suspicious findings: Surface characteristics

(spiculation, angular margins, and microlobulations); shapes (taller than wide, duct

extension, and branch pattern); internal characteristics

(acoustic shadowing, hypoechoic echotexture, and calcifications)

spiculations • Spiculations or thick echogenic

halo • Spiculation (spicule) is a hard

sonographic finding that corresponds to invasion of surrounding tissues and a desmoplastic host response to the lesion. When coarse; alternating

hypoechoic and hyperechoic lines that radiate perpendicular to the surface of the nodule.

• The hypoechoic components represent either fingers of invasive tumor or DCIS components of tumor extending into the surrounding tissues, and the

• The hyperechoic elements represent the interfaces between the spicules and surrounding breast tissues In most cases, however, spicules

are fine and present with only a single echogenicity. They appear to be either hyperechoic or hypoechoic depending on echogenicity of the tissue within which the lesion lies

Echogenic halo with hyperechoic spicule

• Considering the thick echogenic halo to be a variant of frank spiculations approximately doubles the sensitivity of spiculation for malignant nodules, from 36% to 70%.

Angular margins • Jagged or irregular margins • Angular margin represents a hard

sonographic finding indicative of invasion

• A single angle of any type on the surface of the lesion excludes BIRADS 3 category.

• In region of low resistance to invasion • Angular margins have the 2nd best

sensitivity of all the suspicious findings (90%) but have the best combination of sensitivity and positive predictive value of any of the findings.

Microlobulations • Are 1-mm to 2-mm lobulations

that vary in number and distribution along the surface and within the substance of a nodule

• Mixed finding that can be seen with both invasive and DCIS components of tumor (often in situ component)

• When microlobulations are angular and are associated with a thick echogenic halo, they usually represent fingers of invasive carcinoma

• When the microlobulations are rounded and associated with a thin echogenic capsule, they usually represent DCIS components of tumors.

• DCIS components can create microlobulations in two ways: ductules or ducts that are distended with tumor and necrosis

Microlobulation

Taller than wider shape • Suspicious for malignancy • seen with both invasive and DCIS

lesions • Primarily a feature of small, solid

malignant nodules that have a volume 1 cc or less

• As lesions enlarge, they tend to become wider than tall

• The shape of small carcinomas merely reflects the shape of the TDLUs within which the carcinoma arose. Most TDLUs lie in the anterior aspect of the mammary zone and are oriented in a taller-than-wide axis

Terminal ductolobular unit (TDLU) carcinoma

Duct Extension and Branch Pattern • Duct extension and branch

pattern are “soft” shape findings that correlate with the presence of DCIS components of tumor

• Best demonstrated when the scan plane is oriented parallel to the long axis of the mammary ducts in the region of the nodule

• Usually manifests as a single projection of solid growth toward the nipple from the main nodule

Acoustic shadowing

• Suggests the presence of invasive malignancy

calcifications

• Calcifications within solid nodules are soft suspicious sonographic findings that suggest the presence of DCIS components