Development of a Practical Delineation Guidance for Left Anterior Descending Coronary Artery Area in Left Breast Cancer Radiation Therapy

Abstract

Sixteen patients were alive at time of analysis. Median follow-up was 4.1 years for all patients and 14 years for living patients. At 15 years, local control rate was 78%, regional control rate was 92%, and localregional control rate was 74%. Cause-specific and disease-free survival rates were 49% at 5 years and 35% at 10 and 15 years. Fifteen percent had a contralateral breast failure. The rate of distant metastases was 59% at 10 years and 61% at 15 years. Overall survival rate was 48% at 5 years, 32% at 10 years, and 23% at 15 years. The 10 patients who received preoperative RT (median dose, 55 Gy) but not surgery fared poorly, with 9 dying of disease; the median time to death was 1.4 years. The 10-year survival rate for the no-surgery group was 20% compared to 25% in the preoperative RT and surgery group and 35% in the postoperative RT group (P Z 0.22). Patients treated once daily (median dose, 50 Gy) had a 10-year local control rate of 78% and regional control rate of 91%. This was comparable to the twice-daily arm (median dose, 51 Gy), which had a local control rate of 76% (P Z 0.69) and regional control rate of 100% (P Z 0.22). Per CTCAE version 4.0, 26 (30.2%) patients experienced lymphedema: 3 with grade 3; 11 with grade 2; 12 with grade 1. In 5 of these patients, lymphedema was permanent. There were 6 grade 3 and 1 grade 4 complications during chemotherapy. No grade 5 toxicity occurred. Conclusion: IBC is an aggressive disease that is routinely self-detected by patients. Once-daily versus twice-daily RT did not affect control rates in this cohort. Patients who did not receive trimodality therapy, especially those who did not proceed to surgery, had a particularly poor prognosis. Nearly a quarter of patients achieve long-term survival.