Stage IV, Recurrent, and Metastatic Breast Cancer
Recurrent breast cancer is often responsive to therapy, though treatment is rarely curative at this stage of disease. Patients with localized breast or chest wall recurrences, however, may be long-term survivors with appropriate therapy. Prior to treatment for recurrent or metastatic cancer, restaging to evaluate extent of disease is indicated. Cytologic or histologic documentation of recurrent or metastatic disease should be obtained whenever possible. The ER levels and PR levels, HER2/neu positivity at the time of recurrence, and previous treatment should be considered, if known, when selecting therapy. ER status may change at the time of recurrence. In a single small study by the Cancer and Leukemia Group B (MDA-MBDT-8081), 36% of hormone receptor–positive tumors were found to be receptor negative in biopsy specimens isolated at the time of recurrence.[4] Patients in this study had no interval treatment. If ER and PR status is unknown, then the site(s) of recurrence, disease-free interval, response to previous treatment, and menopausal status are useful in selecting chemotherapy or hormone therapy.[5]
Recurrent local-regional breast cancer
Patients with local-regional breast cancer recurrence may become long-term survivors with appropriate therapy. A clinical trial indicated that between 10% and 20% of patients will have locally recurrent disease in the breast between 1 and 9 years after breast-conservation surgery plus radiation therapy.[6] Nine percent to 25% of these patients will have distant metastases or locally extensive disease at the time of recurrence.[7-9] Patients with local-regional recurrence should be considered for further local treatment (e.g., mastectomy). In one series, the 5-year actuarial rate of relapse for patients treated for invasive recurrence after initial breast conservation and radiation therapy was 52%.[8] A phase III randomized study showed that local control of cutaneous metastases could be achieved with the application of topical miltefosine; however, the drug is not currently available in the United States.[10][Level of evidence: 1iiDiii]
Local chest wall recurrence following mastectomy is usually the harbinger of widespread disease, but, in a subset of patients, it may be the only site of recurrence. For patients in this subset, surgery and/or radiation therapy may be curative.[11,12] Patients with chest wall recurrences of less than 3 cm, axillary and internal mammary node recurrence (not supraclavicular, which has a poorer survival), and a greater than 2-year disease-free interval prior to recurrence have the best chance for prolonged survival.[12] The 5-year DFS rate in one series of such patients was 25%, with a 10-year rate of 15%.[13] The local-regional control rate was 57% at 10 years. Systemic therapy should be considered in patients with local regional recurrence caused by the high risk of subsequent metastases.[14] No randomized controlled studies are available to guide patient care in this situation.
Stage IV and metastatic disease
Systemic disease
Treatment for systemic disease is palliative in intent. Goals of treatment include improving quality of life and prolongation of life. Although median survival has been reported to be 18 to 24 months,[15] some patients experience long-term survival. Among patients treated with systemic chemotherapy at a single institution between 1973 and 1982, 263 patients (16.6%) achieved complete responses. Of those, 49 patients (3.1% of the total group) remained in complete remission for more than 5 years, and 26 patients (1.5%) were still in complete remission at 16 years.[16][Level of evidence: 3iiDiii]
Treatment of metastatic breast cancer will usually involve hormone therapy and/or chemotherapy with or without trastuzumab. Radiation therapy and/or surgery may be indicated for patients with limited symptomatic metastases. All patients with metastatic or recurrent breast cancer should be considered candidates for ongoing clinical trials.
Surgery
Surgery may be indicated for selected patients. Examples include patients who need mastectomies for fungating/painful breast lesions, parenchymal brain or vertebral metastases with spinal cord compression, isolated lung metastases, pathologic (or impending) fractures, or pleural or pericardial effusions. (Refer to the PDQ summary on Pain for more information; for information on pleural and pericardial effusions, refer to the PDQ summary on Cardiopulmonary Syndromes.)
Radiation therapy
Radiation therapy has a major role in the palliation of localized symptomatic metastases. Indications include painful bony metastases, unresectable central nervous system metastases (i.e., brain, meningeal, and spinal cord), bronchial obstruction, and fungating/painful breast or chest wall lesions. Radiation therapy should also be given following surgery for decompression of intracranial or spinal cord metastases and following fixation of pathologic fractures. Clinical trials (including the completed Radiation Therapy Oncology Group’s trial [RTOG-9714]) are exploring the optimal radiation fractionation schedule. Strontium 89, a systemically administered radionuclide, can be administered for palliation of diffuse bony metastases.[17,18] (Refer to the PDQ summary on Pain for more information.)