- The breast can be imaged with mammography, ultrasound or MRI
- Mammography is the most sensitive of breast imaging modalities
- Sensitivity is reduced in young women due to the presence of
increased glandular tissue
- For symptomatic patients, imaging always be performed as part of
triple assessment
Mammography
- Abnormalities detected on mammography are classified as:
- Spiculated masses
- Stellate lesions
- Circumscribed masses
- Microcalcification
Spiculated masses
- Soft tissue mass with spicules extending into surrounding tissue
- 95% of spiculated masses are due to invasive cancer
- Other causes of spiculated masses include:
- Ductal carcinoma in-situ (DCIS)
- Radial scar / complex sclerosing lesion
- Fat necrosis
- Fibromatosis
- Granular cell myoblastoma
Stellate lesions
- Localised distortion of the breast parenchyma with no perceptible
mass lesion
- Differential diagnosis of stellate lesions includes:
- Radial scar
- Invasive cancer
- DCIS
- Surgical scar
Circumscribed masses
- Circumscribed masses should be analysed according to density,
outline and size
- Differential diagnosis of circumscribed masses includes:
- Fibroadenoma
- Cyst
- Mucinous or medullary carcinoma
- Lipoma
- Abscess
Microcalcification
- Microcalcification is due to debris within the duct wall or lumen
- Sole feature of 33% of screen-detected cancers
- Malignant microcalcification is usually linear or branching
- Benign microcalcification is usually rounded and punctate
- Differential diagnosis of microcalcification includes:
- DCIS
- Invasive cancer
- Papilloma
- Fibroadenoma
- Fat necrosis
Breast ultrasound
- Ultrasound is useful in the assessment of breast lumps
- Complements mammography and is able to differentiate solid and
cystic lesions
- Also able to guide fine needle aspiration and core biopsies
- Can be used to assess tumour size and response to therapy
- In the diagnosis of malignancy it has a sensitivity and specificity
of 75% and 97% respectively
- Cysts and solid lesions have typical appearances
Cysts
- On ultrasound examination cysts have:
- Smooth walls
- Sharp anterior and posterior borders
- Black hypoechoic centres without internal echoes
Solid lesions
- Solid lesions have internal echoes
- Malignant tumours have:
- Hypoechoic areas interspersed between brighter echoes
- Irregular edges
- Cast hypoechoic shadows
- Benign tumours have:
- Isoechoic or hypoechoic patterns
- Smooth well defined borders
- Cast no hypoechoic shadows
Breast MRI
- Breast MRI is a recently developed technique
- Uses are currently being defined
- Has high sensitivity for multifocal carcinoma
- Has low specificity
- Lesion detected need further assessment by ultrasound and biopsy
- Needs to be performed in second week of menstrual cycle
- Likely uses include:
- Imaging of breast for occult disease in presence of axillary
metastases
- Differentiating between scar tissue and recurrence
- Assessment if breast implants
Bibliography
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Kneeshaw P J, Turnbull L W, Drew P J. Br J Cancer
2003; 88: 4-10
Orel S G. MR imaging of the breast. Radiol Clin North Am 2000;
38: 899-913.
Svensson W E. The value of ultrasound scanning in breast disease.
Hosp Med 2000; 61: 233-239.
van Goethem M, Tjalma W, Schelfout K et al.
Magnetic resonance imaging in breast cancer. EJSO 2006:
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