Kelly C Hewitt1, Phoebe Miller2, Merisa Piper3, Nicolas Prionas4, Jennifer D Son5, Michael Alvarado6, Laura J Esserman6, Jasmine M Wong6, Cheryl Ewing6, Rita A Mukhtar7. 1. St Charles Cancer Center, Bend, OR, USA. 2. School of Medicine, University of California, San Francisco, CA, USA. 3. Division of Plastic Surgery, Department of Surgery, University of California, San Francisco, CA, USA. 4. Department of Radiation Oncology, University of California, San Francisco, CA, USA. 5. Division of General Surgery, Department of Surgery, Georgetown University, DC, USA. 6. Division of General Surgery, Department of Surgery, University of California, San Francisco, CA, USA. 7. Division of General Surgery, Department of Surgery, University of California, San Francisco, CA, USA. Electronic address: rita.mukhtar@ucsf.edu.
Abstract
BACKGROUND: Surgical treatment of invasive lobular carcinoma (ILC) is challenging due to its diffuse growth pattern, and the positive margin rate after mastectomy is poorly described. METHODS: We retrospectively determined the positive margin rate in those with stage I-III ILC undergoing mastectomy. We evaluated the relationship between management strategy and recurrence free survival (RFS). RESULTS: In 357 patients, the positive margin rate was 10.6% overall and 18.7% in those with T3 tumors. Having a positive margin was associated with significantly shorter RFS on multivariate analysis (p = 0.01). Undergoing additional local treatment (radiation or re-excision) for a positive margin was significantly associated with improved RFS (p = 0.004). Older women with positive margins were significantly less likely to undergo additional local therapy. CONCLUSIONS: Even mastectomy fails to clear margins in a high proportion of patients with large ILC tumors, a finding which may warrant testing neoadjuvant strategies even prior to planned mastectomy.
BACKGROUND: Surgical treatment of invasive lobular carcinoma (ILC) is challenging due to its diffuse growth pattern, and the positive margin rate after mastectomy is poorly described. METHODS: We retrospectively determined the positive margin rate in those with stage I-III ILC undergoing mastectomy. We evaluated the relationship between management strategy and recurrence free survival (RFS). RESULTS: In 357 patients, the positive margin rate was 10.6% overall and 18.7% in those with T3 tumors. Having a positive margin was associated with significantly shorter RFS on multivariate analysis (p = 0.01). Undergoing additional local treatment (radiation or re-excision) for a positive margin was significantly associated with improved RFS (p = 0.004). Older women with positive margins were significantly less likely to undergo additional local therapy. CONCLUSIONS: Even mastectomy fails to clear margins in a high proportion of patients with large ILC tumors, a finding which may warrant testing neoadjuvant strategies even prior to planned mastectomy.