After a suspicious finding is seen using mammography or other screening modalities, biopsy is performed in order to guide treatment decisions. Current staging of breast cancer is determined by the American Joint Committee on Cancer (AJCC). It is a TNM (tumor, node, metastasis) system based on pathological and clinical findings.
Treatment for locally invasive breast carcinoma today is based on a multidisciplinary approach with combined surgery, radiotherapy and adjuvant systemic therapy. A major difference from the historical approach is that radical mastectomies are rarely indicated. The most common surgical procedure is the modified radical mastectomy, which removes the breast to the underlying pectoral fascia and includes some of the adjacent lymph nodes. This procedure is equivalent in efficacy to the classic radical mastectomy. Breast conserving therapy (BCT) or lumpectomy removes only the bulk of the tumor and moderate dose radiation therapy (RT) is then used to eradicate remaining cancerous cells. This is an important issue since it has been shown that additional cancer foci exist at a distance from the primary site. However, BCT with RT has been shown to be equivalent to modified radical mastectomy in both survival and local recurrence6. Adjuvant systemic therapy decreases the likelihood of local recurrence when combined with BCT and RT, but not after BCT alone.
The addition of RT to systemic therapy (chemotherapy or hormonal therapy) following mastectomy in node-positive patients decreases local recurrence rates and moderately improves survival. Radiation therapy should be considered on an individual basis due to its late cardiac mortality and other serious complications.