Outcome of Isolated Sternal Recurrence in Breast Cancer

Introduction: Metastatic breast cancer to sternum is rare and its natural history and prognosis are not fully understood. Metastasis to sternum is considered as stage IV, but may represent local extension from internal mammary nodes. Here we present a case series of 7 patients with metastatic breast cancer to sternum with and without internal mammary node involvement.Method: Seven patients were identified by 5 medical oncologists from New York area with busy breast cancer practices, from 1991 to 2008. Patients chart were reviewed and information regarding age, menopausal status, hormone receptor status, Her2/neu status, initial treatment, time to sternal recurrence and treatment of metastatic disease were obtained.Results: Out of 7 patients with stages I to III at diagnosis, 4 were premenopausal. Two patients had triple negative tumors, 3 were ER/PR positive and 2 were Her2 positive. All patients received loco-regional treatment of the primary site with surgery and/or radiation. Five patients received adjuvant or neoadjuvant chemotherapy. Median time to sternal recurrence was 3 years. Two patients had biopsy confirmed metastasis to internal mammary nodes at relapse. All patients with recurrence received either chemotherapy, radiation or hormonal therapy. One patient received autologous bone marrow transplant after sternal recurrence. All 7 patients are alive, 5 of them in remission and 2 patients with stable disease. Median DFS in 5 patients with CR was 7.8 years.Conclusion: Isolated sternal recurrence with/without internal mammary node involvement is relatively uncommon and is classified as stage IV. On our review of 7 cases, 5 remain in continuous remission at a median of 8 years from recurrence. The other two patients have stable disease. These sternal lesions could possibly represent loco-regional recurrence rather than systemic relapse. Hence, isolated sternal recurrence from breast cancer may need to be stratified separately in studies of stage IV disease.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3054.