Multimodality imaging of the breast- BI-RADS

Imaging of the breast

1. Mammography & Ultrasound Lexicon Breast Imaging Reporting and Data System – BI-RADS Breast Imaging Reporting and Data System – BI-RADS

2. BI-RADS Assessment Categories

3. a- The breast are almost entirely fatty. Mammography is highly sensitive in this setting. b- There are scattered areas of fibroglandular density. The term density describes the degree of x-ray attenuation of breast tissue but not discrete mammographic findings. c- The breasts are heterogeneously dense , which may obscure small masses. Some areas in the breasts are sufficiently dense to obscure small masses. d - The breasts are extremely dense , which lowers the sensitivity of mammography. Breast Composition BI-RADS 2013

4. Mass A 'Mass' is a space occupying 3D lesion seen in 2 different projections. If a potential mass is seen in only a single projection it should be called a 'asymmetry' until its 3-dimensionality is confirmed. Shape : oval (may include 2 or 3 lobulations), round or irregular Margins : circumscribed, obscured, microlobulated , indistinct, spiculated Density: high, equal, low or fat-containing.

5. Architectural distortion The term architectural distortion is used, when the normal architecture is distorted with no definite mass visible. This includes thin straight lines or spiculations radiating from a point, and focal retraction, distortion or straightening at the edges of the parenchyma. The differential diagnosis is scar tissue or carcinoma. Architectural distortion can also be seen as an associated feature. For instance if there is a mass that causes architectural distortion, the likelihood of malignancy is greater than in the case of a mass without distortion.

6. Findings that represent unilateral deposits of fibroglandular tissue not conforming to the definition of a mass. Asymmetry as an area of fibroglandular tissue visible on only one mammographic projection, mostly caused by superimposition of normal breast tissue. Focal asymmetry visible on two projections, hence a real finding rather than superposition. This must be differentiated from a mass. Global asymmetry consisting of an asymmetry over at least one quarter of the breast and is usually a normal variant. Developing asymmetry new, larger and more conspicuous than on a previous examination.

7. Exception of the rule : an isolated group of punctuate calcifications that is new, increasing, linear, or segmental in distribution, or adjacent to a known cancer can be assigned as probably benign or suspicious.

8. Amorphous (BI-RADS 4B) So small and/or hazy in appearance that a more specific particle shape cannot be determined. Coarse heterogeneous (BI-RADS 4B) Irregular, conspicuous calcifications that are generally between 0,5 mm and 1 mm and tend to coalesce but are smaller than dystrophic calcifications. Fine pleomorphic (BI-RADS 4C) Usually more conspicuous than amorphous forms and are seen to have discrete shapes, without fine linear and linear branching forms, usually < 0,5 mm. Fine linear or fine-linear branching (BI-RADS 4C) Thin, linear irregular calcifications, may be discontinuous, occasionally branching forms can be seen, usually < 0,5 mm.

9. Distribution of calcifications The arrangement of calcifications, the distribution, is at least as important as morphology. These descriptors are arranged according to the risk of malignancy: Diffuse: distributed randomly throughout the breast. Regional: occupying a large portion of breast tissue > 2 cm greatest dimension Grouped (historically cluster): few calcifications occupying a small portion of breast tissue: lower limit 5 calcifications within 1 cm and upper limit a larger number of calcifications within 2 cm. Linear : arranged in a line, which suggests deposits in a duct. Segmental : suggests deposits in a duct or ducts and their branches.

10. Location in Mammography and US A complete set of location descriptors consists of: Designation of right or left breast Quadrant and clockface notation (preferably both) On US quarter and clockface notation should be supplemented on the image by means of bodymark and transducer position. Depth: anterior, middle or posterior third (Mammography only) Distance from nipple A mass is seen in the outer lower quadrant of the left breast at 4 o' clock in the posterior portion of the breast at 4cm distance from the nipple.

11. MRI of the breast - Indications evaluation of the extent of spread of a suspected extensive high-grade carcinoma; evaluation of a suspected multifocal or bilateral neoplasm; monitoring of the response to neoadjuvant chemotherapy; screening of high-risk patients; characterization of an indeterminate lesion (after full assessment with other modalities); detection of occult breast carcinoma (in a patient with adenocarcinoma in an axillary lymph node, or in the presence of metastatic adenocarcinoma of unknown origin); detection of recurrent breast cancer after breast-conserving therapy; differentiation between scar tissue and recurrent tumour; evaluation of implant rupture.

12. Contraindications to breast MRI Contraindications to gadolinium-based contrast media due to allergy, pregnancy, or compromised renal function (eGFR < 30); inability to lie prone; marked kyphosis or kyphoscoliosis; marked obesity; extremely large breasts; Implantable devices that are not MRI compatible; severe claustrophobia (which can be treated with sedatives, if necessary).

13. Lesion morphology (including morphologic description of the enhancement pattern) the kinetic pattern of enhancement. Standard sequences include T1- and T2-WI, with and without fat saturation. Dynamic post contrast using fat saturation. Lesion morphology (including morphologic description of the enhancement pattern) the kinetic pattern of enhancement. Standard sequences include T1- and T2-WI, with and without fat saturation. Dynamic post contrast using fat saturation. Breast MRI technique

14. 3 types of enhancement kinetics curves seen with breast MRI. Type-I curves are slowly enhancing, in which gradual, steady enhancement occurs over about 5 min. Malignancy 6% of lesions Type-II curves show early strong enhancement (increase over a 1–2 min period) with a subsequent plateau phase. Malignancy 6–29% of lesions. Type III or “washout” curves show early strong enhancement (over 1–2 min) , with subsequent decline in enhancement. This produces a characteristic peak dubbed the “the cancer corner,” and is strongly associated with malignancy. Malignancy 29–77% of lesions Both Type-II and Type-III curves should be considered suggestive of malignancy.

15. • Intraductal fluid may be hyperintense on T1-weighted images, complicating the evaluation of enhancement. Post-processing is required to evaluate for true enhancement . • The simplest form of post-processing is subtraction, where the dynamic post-contrast images are subtracted from the initial T1-FS WI. • The maximum-intensity projection (MIP) image is a useful post-processing tool based on the subtraction images. A MIP highlights the brightest pixel along each parallel ray to create a volumetric data set where the enhancement can easily be seen in 3-D space. • Computer-aided detection (CAD) is a helpful adjunct for analysis of contrast-enhanced MRI sequences. CAD allows creation of a colour angiomap , where the colours correspond to different temporal patterns of enhancement. These temporal enhancement curves allow further characterization of a lesion to determine the level of suspicion for malignancy.

16. Tumour angiogenesis and resultant capillary permeability allows early detection of cancer by contrast-enhanced MRI. Because tumour-associated vessels are thought to be relatively large and leaky, quantification of enhancement kinetics would be expected to show rapid enhancement and washout. This principle is the foundation for kinetic analysis in dynamic contrast-enhanced breast MRI. Dynamic contrast-enhanced breast MRI repeatedly images the breast at multiple time points. Enhancement curves can be generated by plotting percent relative enhancement (compared to the unenhanced image) against time. The enhancement curve can be divided into early (within the first 2 minutes) and delayed phases.

17. As per the BI-RADS lexicon, the kinetics of early enhancement can be characterized as slow , medium , and rapid . A malignant lesion would be expected to have rapid early enhancement . Analysis of the delayed phase of enhancement allows one to further stratify the risk of malignancy. The BI-RADS lexicon describes three kinetic patterns of delayed enhancement: Persistent (type I), plateau (type II), washout (type III).

18. • A type I (persistent) curve shows continuously increasing (>10%) enhancement in the delayed phase. Although a type I curve is associated with a benign finding in 83% of cases , up to 9% of malignant lesions may feature a type I curve. • A type II (plateau) curve has an early rise in enhancement, but levels off (within 10%) in the delayed phase. A type II curve is suspicious, although less strongly so than a type III curve. Type II curves reported PPV between 64 and 77%. • A type III (washout) curve has a >10% decrease in signal intensity in the delayed phase and is suspicious for malignancy. A type III curve has a PPV of 87–92%, but is seen in only 21% of malignant lesions. False positive benign lesions that may show washout kinetics include lymph nodes, adenosis, and papillomas . Both Type-II and Type-III curves should be considered suggestive of malignancy.

19. morphology is much more important than the pattern of enhancement. If a mass with malignant morphology (e.g., spiculated margins or rim enhancement) demonstrates type I enhancement , it remains just as suspicious for cancer. Similarly, a small, circumscribed, reniform mass adjacent to a vessel with type III kinetics is a typical appearance for a benign intramammary lymph node and should not be biopsied. In the evaluation of a lesion

20. Case 1 58 yrs. old - Right breast lump

21. Case 2 78 yrs. old female with breast lump. Post excision biopsy

22. Thank You