Breast cancer is a malignancy that is often strongly influenced by age, family history, genetic factors, hormonal exposure, and lifestyle factors.
On physical examination, the patient usually demonstrates a firm breast mass, which may be associated with axillary lymphadenopathy, skin changes, and nipple discharge.
Asymptomatic patients may be diagnosed with breast cancer after abnormal calcifications and/or architectural distortion are noted on a routine screening mammogram.
Treatment requires a multidisciplinary approach, involving breast surgeons, medical oncologists, and radiation oncologists.
Complications of therapy are specific to each modality of treatment, and careful monitoring and preventive therapy for adverse events (e.g., antiemetic pre-medications in the prevention of nausea) are essential.
Primary invasive breast cancer is a malignancy originating in the breast(s) and nodal basins. The term 'invasive' indicates that the malignancy has penetrated past the basement membrane of the duct or lobule of the breast and has spread to the surrounding tissues, but has not spread to other organs.
The American Joint Committee on Cancer TNM (tumour, node, metastasis) staging system classifies invasive breast cancer into the following stages based on the extent of disease: IA, IB, IIA, IIB, IIIA, IIIB, and IIIC. Stages IA, IB, and IIA are generally considered early-stage breast cancer. Stages IIIA, IIIB, and IIIC are generally considered locally advanced breast cancer. Stage IIB can be considered early-stage breast cancer if the tumour is >20 mm but ≤50 mm and has spread to 1 to 3 axillary lymph nodes (i.e., T2 N1 M0), or locally advanced breast cancer if the tumour is >50 mm with no axillary lymph nodal involvement (i.e., T3 N0 M0).
History and exam
Key diagnostic factors
- presence of risk factors
- breast mass
- nipple discharge
- axillary lymphadenopathy
Other diagnostic factors
- skin thickening or discoloration
- retraction or scaling of the nipple
- increasing age
- female sex
- ethnic origin
- positive family history
- genetic mutations
- endogenous oestrogen exposure
- exogenous oestrogen/progestin exposure
- alcohol consumption
- radiation exposure
- benign breast disease
- increased breast density
- mild, moderate, or marked background parenchymal enhancement (BPE) on breast MRI
- reduced physical activity
- poor diet
- high socioeconomic class
- high dibutyl-phthalate exposure
1st investigations to order
Investigations to consider
- breast ultrasound
- breast MRI
- hormone receptor testing
- HER2 testing
- gene expression assays
- computed tomography
- genetic testing
- alkaline phosphatase
early-stage breast cancer (stages I to IIB [T2 N1 M0])
locally advanced breast cancer (stages IIB [T3 N0 M0] to III)
- Fibrocystic changes
- Suspected cancer: recognition and referral
- Management of hereditary breast cancer
Breast cancer, locally advanced: what is it?
Breast cancer: breast-conserving surgeryMore Patient leaflets
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