Breast Imaging PDF

BREAST IMAGING Dr. Shaden AlMousa, MD Radiology Email: [email protected] Mobile:0566976059 OBJECTIVES: ▪ Know various imaging modalities used in breast imaging. ▪ Know breast anatomy. ▪ Identify and describe common pathologies. ▪ BIRAD system ANATOMY: ▪ Nipple: The nipple is a circular smooth m...

BREAST IMAGING Dr. Shaden AlMousa, MD Radiology Email: [email protected] Mobile:0566976059 OBJECTIVES: ▪ Know various imaging modalities used in breast imaging. ▪ Know breast anatomy. ▪ Identify and describe common pathologies. ▪ BIRAD system ANATOMY: ▪ Nipple: The nipple is a circular smooth muscle that overlies the 4th intercostal space. ▪ Fibroglandular Tissue: The breast mound is fibrous tissue with fat, ducts, and glands laying on top of the anterior chest wall. The axillary extension is called the "tail of Spence." The upper outer quadrant is more densely populated with fibroglandular tissue, which is why most breast cancers start there. ▪ Cooper's Ligaments: These are thin sheets of fascia that hold the breasts up. ▪ Lobules: The lobules are the flower shaped milk makers of the breast. The terminal duct and lobule are referred to as a "terminal duct lobular unit" or TDLU. This is where most breast cancers start. ANATOMY ▪ Ducts: The ductal system branches like the roots or branches of a tree. The calcifications that appear to follow ducts ("linear or segmental") are the ones where you should worry about cancer. ▪ Lactiferous Sinus: Milk from the lobules drains into the major duct under the nipple. The dilated portion of the major duct is sometimes called the lactiferous sinus. Blood Supply/ Lymphatic Drainage: The majority (60%) of blood flow to the breast is via the internal mammary. The rest is via the lateral thoracic and intercostal perforators. Nearly all (97%) of lymph drains to the axilla. The remaining 3% goes to the internal mammary nodes.  ANATOMY ▪ Axillary Node Levels: The axilla is sub-divided into three separate levels using the pectoralis minor muscle as a landmark. Supposedly drainage progresses in a step wise fashion - from level 1 -> level 2 -> level 3 and finally into the thorax. ▪ Rotter Nodes: These are the nodes between the pectoralis minor and major, these are at the same level as level 2. ANATOMY ▪ Axillary Lymph Node Levels Level 1 : Lateral to Pec Minor Level 2: Deep to the Pec Minor Level 3: Medial and Above Pec Minor Rotter Node: Between the Pec Minor and Major ▪ Metastasis to the Internal Mammary Nodes: If you can see them on ultrasound they are abnormal. Isolated mets to these nodes is not a common situation (maybe 3%). When you do see it happen, it's from a medial cancer. Or More commonly, mets in this location occur after disease has already spread into the axilla (in other words - it's spreading everywhere). IMAGING MODALITY ❑ MAMMOGRAPHY SCREENING DIAGNOSTIC FOLLOW UP ❑ BREAST ULTRASOUND ❑ BREAST MRI STAGING ❑ CT ❑ BONE SCAN IMAGING MODALITY ▪ Mammogram. IMAGING MODALITY ▪ MRI IMAGING MODALITY ▪ Ultrasound. IMAGING MODALITY ▪ CT scan. IMAGING MODALITY ▪ Bone scan.  MAMMOGRAPHY ▪ Screening INDICATIONS: 1) Annual examination starting at age of 40 2) High risk: at age of 30 or 10 years prior to age of discovery of breast cancer in mother. ▪ Diagnostic INDICATIONS: 1. Palpable lump 2. Asymmetry 3. Nipple discharge 4. Skin changes 5. Dilated veins 6. Retracted nipple 7. Axillary lymphadenopathy MAMMOGRAPHY MAMMOGRAPHY ▪ a screening mammogram starts with two standard views; a cranial caudal view and a medial lateral oblique view. MAMMOGRAPHY ▪ Additional views depending on the findings: SIGNS OF CANCER BY MAMMOGRAPHY 1. Asymmetry 2. Architecture distortion 3. Mass 4. Nipple retraction 5. Skin thickening 6. Calcifications WHAT IS A LEXICON ? ▪ “A book containing a clearly defined vocabulary list used by a person , in a language or in a branch on knowledge “ ▪ This ensures that when a group of people use the same terms, the terms means the same thing for every individual person in the group  BI-RADS ▪ Bl-RADS is an acronym for Breast Imaging-Reporting and Data System. It was developed by the ACR to keep everyone on the same page. BI-RADS Assessment Categories: ▪ 0: Incomplete ▪ 1: Negative ▪ 2: Benign finding(s) ▪ 3: Probably benign - < 2 % Chance of CA ▪ 4: Suspicious abnormality - 2 - 95% Chance of CA ▪ Some people use 4a (low suspicion), 4b (intermediate suspicion), and 4c (moderate suspicion). ▪ 5: Highly suggestive of malignancy-> 95% Chance of CA ▪ 6: Known biopsy - proven malignancy BI-RADS ▪ Bl-RADS 0: This is your incomplete workup. They come in for a screener, you find something suspicious. You give it a Bl-RADS 0, and bring them back for spots, mags, or ultrasound. You would also Bl-RADS 0 anything that required a technical repeat (blur,inadequate posterior nipple line, camel nose, etc.... ). ▪ Bl-RADS 1: It 's normal. ▪ Bl-RADS 2: Benign findings. Examples would be cysts , secretory calcifications, fat containing lesions such as oil cysts, lipomas, galactoceles and mixed-density hamartomas. Multiple bilateral well circumscribed, similar appearing masses - This is BR-2 unless one is growing or different than the rest. The general rule is to not ultrasound these things unless one is palpable. Multiple Foci - This MRI finding is also a classic BR2. BI-RADS ▪ Bl-RADS 3: A key point is that BR-3 by definition means it has less than 2% chance of being cancer. You can only use BR3 on a baseline. You can't call anything BR3 that is new. The typical BR3 scenario: 45 year old comes in for screening and has a focal asymmetry. She gets called back for diagnostic work up with spots and ultrasound. She is found to have mass with imaging features classic for fibroadenoma. This can get a BR-3, and be followed (some places follow for 2 years, in 6 month intervals). Any change over that time ups it to BR-4 and it gets a biopsy. ▪ Things you can BR-3: Finding consistent with fibroadenoma Focal asymmetry that looks like breast tissue (becomes less dense on compression). Grouped Round Calcifications BI-RADS ▪ Bl-RADS 4: This is defined as having a 2-95% chance of malignancy. Some people will subdivide this into 4A, 4B, 4C depending on the level of suspicion. Ultimately you are going to biopsy it, and be prepared to accept a benign result. ▪ Bl-RADS 5: This is defined as> 95% chance of malignancy. When you give a BR-5 , you are saying to the pathologist "if you give me a benign result, I' ll have to recommend surgical biopsy." In other words, you can't accept benign with a BR-5. ▪ Bl-RADS 6: This is path proven cancer. MAMMOGRAPHY ▪ Breast Composition  BREAST COMPOSITION ▪ A- The breasts are almost entirely fatty. Mammography is highly sensitive in this setting. ▪ B- There are scattered areas of fibro-glandular 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.  SIGNS OF CANCER BY MAMMOGRAPHY 1. Asymmetry 2. Architecture distortion 3. Mass 4. Nipple retraction 5. Skin thickening 6. Calcifications an example of a focal asymmetry seen on MLO and CC-view. Left upper outer quadrant focal area of asymmetry. It occupies less than 25% of the breast and seen in two views. We have to proceed to another imaging modality or more views. Local compression views and ultrasound did not show any mass. THIS IS AN EXAMPLE OF GLOBAL ASYMMETRY. IN THIS PATIENT THIS IS NOT A NORMAL VARIANT, SINCE THERE ARE ASSOCIATED FEATURES, THAT INDICATE THE POSSIBILITY OF MALIGNANCY LIKE SKIN THICKENING, THICKENED SEPTA AND SUBTLE NIPPLE RETRACTION. THE PET-CT SHOWS DIFFUSE INFILTRATING CARCINOMA. SIGNS OF CANCER BY MAMMOGRAPHY 1. Asymmetry 2. Architecture distortion 3. Mass 4. Nipple retraction 5. Skin thickening 6. Calcifications  ARCHITECTURE DISTORTION ▪ The term architectural distortion is used, when the normal architecture is distorted with no definite mass visible. The differential diagnosis is scar tissue or carcinoma. ▪ Includes speculations radiating from a point, and focal retraction, distortion or straightening at the edges of the parenchyma. ▪ 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.  SIGNS OF CANCER BY MAMMOGRAPHY 1. Asymmetry Irregular speculated high density retro 2. Architecture distortion areolar mass associated with 3. Mass architectural distortion. There is 4. Nipple retraction over lying skin thickening and slight 5. Skin thickening nipple retraction.(BIRAD 5) 6. Calcifications  BREAST MASS ▪ A 'Mass' is a space occupying 3D lesion seen in two different projections. ▪ How to describe a mass? Shape: round, oval or irregular Margins: well-circumscribed, obscured, lobulated, indistinct, spiculated Density: high, equal, low or fat-containing.  THE SHAPE OF A MASS IS EITHER ROUND, OVAL OR IRREGULAR. ALWAYS MAKE SURE THAT A MASS THAT IS FOUND ON PHYSICAL EXAMINATION IS THE SAME AS THE MASS THAT IS FOUND WITH MAMMOGRAPHY OR ULTRASOUND. The margin of a lesion can be: 1- Well-circumscribed (well-defined), this is a benign finding. 2- Obscured or partially obscured, when the margin is hidden by superimposed fibro-glandular tissue. Ultrasound can be helpful to define the margin better. The margin of a lesion can be: 3- INDISTINCT (ILL-DEFINED), THIS IS ALSO A SUSPICIOUS FINDING. 4- SPICULATED WITH RADIATING LINES FROM THE MASS IS A VERY SUSPICIOUS FINDING. Margins  THE DENSITY OF A MASS IS RELATED TO THE SURROUNDING FIBRO-GLANDULAR TISSUE. HIGH DENSITY IS ASSOCIATED WITH MALIGNANCY. IT IS EXTREMELY RARE FOR BREAST CANCER TO BE LOW DENSITY. SIGNS OF CANCER BY MAMMOGRAPHY 1. Asymmetry A grouped 2. Architecture distortion pleomorphic 3. Mass microcalcification with no gross 4. Nipple retraction underlying mass 5. Skin thickening lesion. 6. Calcifications  CALCIFICATIONS ▪ Calcifications are either typically benign or of suspicious morphology. ▪ Within the suspicious group the chances of malignancy are different depending on their morphology and also depending on their distribution. Suspicious Calcifications Morphology 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. Suspicious Calcifications Morphology 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.  DISTRIBUTION OF CALCIFICATIONS ▪ 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.  Morphology: some are coarse heterogenous and some look more like fine pleomorphic. Distribution: Some calcifications are in a group ( 2cm), but not in a segmental or linear arrangement. This proved to be multifocal DCIS with areas of invasive carcinoma The images show a fat-containing lesion with a popcorn-like calcification. All fat-containing lesions are typically benign. These image-findings are diagnostic for a hamartoma - also known as fibroadenolipoma Oval ,partially circumscribed encapsulated lesion with heterogeneous density in retroareolar region of right breast. It consists of both fat and soft tissue density. No intralesional calcification is noted. No skin thickening or nipple retraction is noted. 🡪benign hamartomatous lesion (fibroadenolipoma). It results from a benign proliferation of fibrous, glandular, and fatty tissue (hence fibro-adeno-lipoma) Also called as BREAST WITHIN BREAST APPEARANCE The calcifications on the left were detected on the first mammogram in a screening program. There is a cluster of amorphous and fine pleomorphic calcifications. These calcifications were classified as BI-RADS 4. A biopsy was performed and only fibrocystic changes were found. BENIGN CALCIFICATIONS: ▪ Dermal Calcifications. ▪ Vascular Calcifications. ▪ Popcorn Calcifications. ▪ Secretory (Rod-Like) Calcifications. ▪ Eggshell Calcifications. ▪ Dystrophic Calcifications. ▪ Round. ▪ Milk of Calcium. DDX OF SUSPICIOUS CALCIFICATIONS: BREAST ULTRASOUND  INDICATIONS OF BREAST ULTRASONOGRAPHY ▪ Cystic versus solid masses ▪ Characterization of solid masses (benign versus malignant features) ▪ Evaluation of masses in patients who can not perform mammography like pregnant, lactating or below age of 30 years women ▪ Guiding for biopsy and aspiration  Breast Composition: oHomogeneous echotexture-fat oHomogeneous echotexture- fibro-glandular oHeterogeneous echotexture CYSTI C OR SOLID MASS Here a typical example of multiple cysts in a woman who felt a lump in her breast.  SIGNS OF CANCER BY ULTRASONOGRAPHY 1. Mass 2. Hypo-echoic 3. Spiculated 4. Taller than wider 5. Posterior shadowing 6. Dilated ducts 7. Calcifications ▪ Architectural distortion ▪ Duct changes ASSOCIATED ▪ Skin changes FEATURES ▪ Edema ▪ Vascularity ▪ Elasticity assessment  CALCIFICA TIONS ▪ On US poorly characterized compared with mammography, but can be recognized as echogenic foci, particularly when in a mass. ULTRASOU ND NEEDLE GUIDED BIOPSY  MASS ▪ Orientation: unique to US-imaging, and defined as parallel (benign) or not parallel (suspicious finding) to the skin. Echo pattern: anechoic, hypoechoic, complex cystic and solid, isoechoic, hyperechoic, heterogeneous. Echogenicity can contribute to the assessment of a lesion, together with other feature categories. Alone it has little specificity. dermoid cyst. It is located in the subcutis and connected to the skin. Posterior features: enhancement, shadowing. Posterior features represent the attenuation characteristics of a mass with respect to its acoustic transmission, also of additional value. Alone it has little specificity. Fibroadenoma. Transverse image reveals a typical larger transverse than anteroposterior diameter (or wider than taller mass……> parallel ), homogenous echotexture , hypoechoic, and a thin capsule (arrowheads) BREAST MRI  Use of breast MRI 1. characterization of lesions 2. discrimination between benign and malignant breast lesions 3. preoperative staging 4. tumor size estimation 5. detection of the invasive component in DCIS lesions 6. detection of additional tumor foci in the ipsilateral and contralateral breast 7. to improve breast cancer surgery 8. to document response in patients treated with neoadjuvant chemotherapy 9. abbreviated MRI protocols are being used for screening purposes in high-risk patients like those with BRCA gene mutation showing that it detects most breast cancers at an early stage 13 10. superior to mammography when assessing patients with dense breast parenchyma to detect additional occult cancer foci  Clinical indications for breast MRI ACR guidelines 1. high-risk screening 1. personal history 2. family history 3. high-risk lesions: ADH/ALH/LCIS 4. BRCA1 / BRCA2 gene positivity 5. mantle radiotherapy (>4 gray) 2. extent of disease (EOD) evaluation in ipsilateral and contralateral breast 3. neo-adjuvant chemotherapy: to assess residual disease 4. metastatic axillary lymphadenopathy of unknown primary (75 - 80% sensitive) 5. posterior lesion to assess chest wall invasion (pectoralis can be resected so not considered 6. chest wall stage IIIB - serratus anterior muscle, rib, intercostal muscles) STAGING BY CT AND BONE SCANS BREAST CANCER AND LUNG METS. METASTATI C BREAST CANCER BY PET SCAN  HIGH RISK BREAST LESIONS ▪ There are 5 classic high risk lesions that must come out after a biopsy; Radial Scar, Atypical Ductal Hyperplasia, Atypical Lobular Hyperplasia, LCIS, and Papilloma. ▪ Radial Scar: This is not actually a scar, but does look like one on histology. Instead you have a bunch of dense fibrosis around the ducts giving the appearance of architectural distortion (dark scar). Things to know: A. This is high risk and has to come out B. It's associated with DCIS and/or JDC 10%-30% C. It's associated with Tubular Carcinoma* ▪ Atypical Ductal Hyperplasia (ADH): This is basically DCIS but lacks the quantitative definition by histology( < 2 ducts involved). It comes out (a) because it's high risk and (b) because DCIS burden is often underestimated when this is present. In other words, about 30% of the time the surgical path will get upgraded to DCIS. HIGH RISK BREAST LESIONS ▪ Lobular Carcinoma in Situ (LCIS): This is classically occult on mammogram. "An incidental finding" is sometimes a buzzword. The best way to think about LCIS is that it can be a precursor to ILC, but isn't obligated to be. ▪ Atypical Lobular Hyperplasia (ALH): This is very similar to LCIS, but histologists separate the two based on if the lobule is distended or not (no with ALH, yes with LCIS). It’s considered milder than LCIS (risk of subsequent breast CA is 4-6x higher with ALH, and 11 x higher with LCIS). For the CORE, the answer is excision. In the real world, some people do not cut these out, and it's controversial. ▪ Papilloma: A few most commons come to mind with this one. Most common intraductal mass lesion. Most common cause of blood discharge. You typically see these in women in their late reproductive years / early menopausal years (average around 50). The classic location is the subareolar region ( I cm from the nipple in 90% of cases). MALE BREAST ▪ The male breast does NOT have the elongated and branching ducts, or the proliferated lobules that women have. This is key because men do NOT get lobule associated patholog y (lobular carcinoma, fibroadenoma, or cysts).  MALE BREAST ▪ Gynecomastia: This is a non-neoplastic enlargement of the epithelial and stromal elements in a man's breast. It occurs "physiologically“ in adolescents, affecting about 50% of adolescent boys, and men over 65. If you are between 13-65 it's considered pathology and associated with a variety of conditions (spironolactone, psych meds, marijuana, alcoholic cirrhosis, testicular cancer). There are three patterns (nodular is the most common). Just think flame shaped, behind nipple, bilateral but asymmetric, and can be painful. Things that make you worry that it's not gynecomastia include not being behind the nipple, eccentric location , and calcification. MALEH BREAST MALE BREAST ▪ Pseudogynecomastia: This is an increase in the fat tissue of the breast (not glandular tissue). There will NOT be a discrete palpable finding, and the mound of tissue will not be concentric to the nipple. ▪ Lipoma: After gynecomastia, lipoma is the second most common palpable mass in a man.  MALE BREAST ▪ Male Breast Cancer: It's uncommon in men, and very uncommon in younger men (average age is around 70). About 1 in 4 males with breast cancer have a BRCA mutation (BRCA 2 is the more common). Other risk factors include Klinefelter Syndrome, Cirrhosis, and chronic alcoholism. ▪ The classic description is eccentric but near the nipple. It's almost always an IDC-NOS type. DClS can occur but is very rare in isolation. On mammography it looks like a breast cancer. ▪ Things that make you think its breast cancer: 1. Eccentric to Nipple 2. Unilateral 3. Abnormal Lymph nodes 4. Calcifications 5. Looks like breast cancer Cases Here a hyperdense mass with an irregular shape and a spiculated margin. Notice the focal skin retraction. This was reported as BI-RADS 5 and proved to be an invasive ductal carcinoma Magnified view shows grouped pleomorphic/coarse heterogeneous microcalcification with no gross underlying mass. BIRAD 4 The upper image shows a few amorphous calcifications initially classified as BI-RADS 3. At 12 month follow up more than five calcifications were noted in a group. The findings were now classified as BI-RADS 4. This proved to be DCIS with invasive carcinoma. Irregular spiculated high density mass associated with pleomorphic microcalcification. BIRAD 5 Rounded circumscribed high density mass in lower inner quadrant. US / oval circumscribed heterogenous echogenicity lesion appear wider than taller with internal thick septation and slight posterior acoustic enhancement. Doppler image shows flow(internal vascularity) within the lesion. BIRAD 5. Oval shaped circumscribed equal density mass associated with two foci of internal macrocalcification at the upper breast BIRAD2( involuted fibroadenoma). US oval shaped circumscribed homogenously hypoechoic mass wider than taller( parallel to the skin) with minimal posterior acoustic enhancement. BIRAD 3 (fibro adenoma). Irregular micro lobulated heterogeneously hypoechoic mass appear taller than wider with thick echogenic capsule. BIRAD 5. Thank You