RADIOLOGIC EVALUATION OF BREAST CANCER Orsolya Farkas, Gabriella Bodrogi and Gábor Szalai Department of Radiology, Pécs University Orsifarkas@yahoo.com
Complex evaluation of the breast Patient history Physical examination Mammography Ultrasound MRI Nuclear medicine (isotope infiltration for sentinel l.g.; PET) Cytology/Histology (Invasive methods - galactography, cyst punction, drainage, lesion localization)
Patient history & physical examination Any subjective complaint Gynecological surgeries, interventions Family history Previous brest surgeries or biopsies Any alteration in brest shape Palpable lesions Nipple discharge Skin thickening Skin retraction Birthmarks, moles
X-ray mammomgraphy Mammography is the main radiologic method to investigate the breast US and MRI mainly have only complementary roles Mammography is the only suitable method for breast cancer screening Mammograms must be evaluated only by trained and certified radiologists
Screening mammomgraphy Searching for cancer signs in females with no symptoms to find cancer in very early stage Hungary: 45-65 y.o., every second year, by invitation High risk patients: familial, brca mutation: > 30y.o., annual
Screening mammography Standard views of each breast (CC + MLO) Mammograms can be evaluated later Does not provide definite diagnosis false negative (dense breast, non-calcified DCIS, lobular cc), false positive Double reading!!! If no consensus or if any alteration: complementary examinations: enlarged views, US, biopsy
Clinical mammography Complex diagnostics Mammograms are evaluated immediately and can be immediatelly completed by additional mammograms (e.g. enlarged views), US, biopsy Women w symptoms, follow up; asymptomatic women
Mammomgraphy technical considerations Requires the best image quality Most pathologies either have soft tissue density that is not very different from surrounding tissues or contain microcalcifications Soft x-rays to best differentiate between the soft tissues of the breast
Mammomgraphy technical considerations Low energy (25-32 kv) High mas Molybdenum (and rhodium) anode (characteristic x-ray production) Molybdenum filter Two, small focal spots (improved resolution) Compression more uniform breast thickness reduced blurring from patient motion reduced scattered radiation reduced radiation dose better visualization of tissues near the chest wall Grid: filter scattered radiation
Mammography
Mammography
Mammography standard views Craniocaudal (CC)
Mammography standard views Mediolateral oblique (MLO)
Left craniocaudal Left mediolateral oblique
Right craniocaudal Right mediolateral oblique
Mammography magnification views Mainly to evaluate microcalcifications
Ultrasound First method of choice under 30 year (+ pregnancy and breast feeding, implants) Complementary method for dense breasts (limitation of mammography!) Further characterization of pathologies found on mammograms Axilla!! - Always has to be scanned Differentiate between solid and cystic lesions Post surgical complications (hematoma) Guiding interventions (FNAB or core biopsy)
Ultrasound Technical considerations High frequency (10-12 MHz), linear probe Doppler: vascularization of lesions (high vascularization and high flow are suspicious for malignancy) Sonoelastography: compare and quantify tissue elasticity malignant lesions usually show higher stiffness relative to surrounding tissue
Fibroadenoma: well-circumscribed, round to ovoid, or macrolobulated mass with generally uniform hypoechogenicity, pseudocapsule Cyst: anechoic, well circumscribed, acoustic enhancement
Breast cancer: echopoor, inhomogeneous, irregular border, poorly circumscribed, acoustic shadow, not compressible
Lesion analysis Ultrasound morphology Benign Anechoic or echopoor Round or oval Well circumscribed Homogeneous Acoustic enhancement Lateral shadow sign Compressible Not fixed No hypervascularity Malignant Echopoor Irregular Ill-defined border Inhomogeneous Acoustic shadow Non-compressible Fixed Hypervascularity and flow, irregular vessels
Ductal cc: stiff lesion Fibroadenoma: elastic lesion
MRI Suspected multifocal, bilateral lesions Occult primary tumor Exact extension of infiltrative lesions Suspected lobular cc. Chest wall infiltration To differentiate between recurrence and surgical scar Suspected implant rupture Screening in high risk populations (e.g. Brca mutation) Monitoring the effect of neoadjuvant chemotherapy
MRI technical considerations Min. 1.5 T (3T) Breast coils Native + contrast enhanced serials T1, T2, FatSat Dynamic MRI!!!: kinetics of contrast enhancement most important to differentiate between benign and malignant lesion
T1 FatSat CE, early phase, subtarction T2
Type I curve: Slow rise, continued rise with time. 6 % malignant. Type III curve: Rapid initial rise, followed by washout. 29-77% malignant.
Anatomy Glandular ducts and lobules Connective tissue Fat Basic functional unit: Lobule or terminal ductal lobular unit (TDLU) Most invasive cancers rise from TDLU (+ DCIS, lobular cc in situ or infiltrating lobular cc, fibroadenoma, fibrocystic disease)
TDLU
How to interpret mammograms? Determine whether film is of diagnostic quality Find the lesion Analyze the lesion Circumscribed Stellate Structural distorsion Calcifications Thickened skin
Determine whether film is of diagnostic quality On MLO views, pectoral muscles should be visible at least above the level of the nipple On CC views, the edge of the pectoral muscle should be visible
Determine whether film is of diagnostic quality The line drawn from the nipple to the pectoral muscle should be the same length on both views (max. difference should be less than 1 cm) trained technitian! 129 mm
Determine whether film is of diagnostic quality Nipple should be in profil
Determine whether film is of diagnostic quality Image should not be blurred
Determine whether film is of diagnostic quality No artefacts! Bra strap Skin folds talcum ointment deodorant patch
Find the lesion Circumscribed easy to recognize; mostly benign Stellate difficult to recognize; most malignant lesions Certain breast types are not easy to evaluate on mammograms
Normal breast types (Tabar) Different types of breasts according to mammographic patterns (reflects composition) I: balanced proportion of all components of breast tissue with a slight predominance of fibrous tissue (Fibroglandular; young age) II: predominance of fat tissue (Fatty breast) III: predominance of fat tissue with retroareolar residual fibrous tissue IV: predominantly nodular densities (Adenotic) V: predominantly fibrous tissue (Fibrotic or dense breast) I-III. Can change e.g. with age or hormon therapy IV and V.: genetically coded; difficulte to evaluate on mammograms!!! US!
Normal breast types (Tabar) Fibroglandular
Normal breast types (Tabar) Involuted
Normal breast types (Tabar) Retroaleolar
Normal breast types (Tabar) Adenotic limitations of mammography!
Normal breast types (Tabar) Fibrotic - limitations of mammography!
Lesion analysis circumscribed lesions cyst, lipoma, fibroadenoma, papillary or mucinous cc, etc Easier to recognize Size Contour (sharp: usually benign feature) Halo, capsule: Benign features Density: radiolucent (lipoma, oil cyst, galactocele); radiolucent and radiopaque combined (l.g., hematoma, fibroadenolipoma); low density radiopaque (fibroadenoma, cyst, but: papillary cc, mucinous cc); high density radiopaque (cc, cyst, abscess, lg...)
Sharp contour - fibroadenoma
Sharp contour - Cyst
Ill defined contour - cc
Capsule Halo
High density radiopaque - cyst Lower density radiopaque - fibroadenoma Radiokucent and radiopaque combined - fibroadenolipoma
Lesion analysis stellate lesions = radiating structure w ill defined borders More difficult to recognize Center distinct mass - white star : invasive intraductal cc oval or circular radiolucent area - black star : radial scar, fat necrosis, invasive lobular cc Radiating structures sharp dense, fine lines radiating in all directions (invasive ductal cc) Many very fine spicules bunched together (radial scar, fat necrosis) Skin thickening: radial scar never associated w
Lesion analysis Radial scar = sclerosing ductal hyperplasia Benign but can be associated with DCIS or tubular cc Mimicker of scirrhous breast cc (invasive ductal cc) 40-60 y.o. Not palpable Mammo: dark star stellate lesion with translucent, low density center w/o mass No associated skin thickening
Lesion analysis Invasive ductal cc Most frequent type of breast cc Peak: 50-60 y.o. Can be palpable, immobile Mammo: white star stellate lesion with high density central mass w calcification (granular or casting); the larger the central mass, the longer the spicules; w/o localized skin thickening or retraction
Lesion analysis Structural distorsion Asymetric densities w architectural distortion Difficult to recognise Lobular carcinoma: often multifoca and bilateral MRI! Mammo: white star Structural distorsion dark star calcification uncommon
Lesion analysis Calcifications Localization: ductal (malignant) or lobular (benign), extraglandular Terms: cluster, scattered, casting, granular, punctuate Malignant type calcifications: Granular: tiny, dot-like, innumerable, irregularly grouped Casting: casts of ductal lumen, irregular outline, polymorph
Lesion analysis Calcifications Benign type calcifications: Egg shell Course or popcorn like Milk of calcium Skin, vascular, etc Large, rod like (plasma cell mastitis)
Lesion analysis DCIS Ductal carcinoma in situ 25-40 % of breast cc on mammomgrams!!! (screening!!!!!) Mammo: 75 % Calcification!!!! Granular or casting
Lesion analysis Thickened skin sy Diffuse or localized Diffuse: Axillary lymphatic obstruction lg. met Breast cc Lymphoma Advanced gynecologic malignancies (ovarium, uterus) Advanced bronchus or esophagus cc Lymphangitic spread of breast cc Inflammation Right heart failure
Special type cancers DCIS, invasive ductal cc ~ 70 % Special types ~ 25 % Lobular: diffuse infiltration, structural distortion difficult to recognize Medullary, Mucinous, Papillary cc: usually well circumscribed, round lesions Metastasis: also circumscribed Lymphoma