Locoregional Recurrence Risk for Patients With T1,2 Breast Cancer With 1-3 Positive Lymph Nodes Treated With Mastectomy and Systemic Treatment
- Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)
- Department of Surgical Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)
- Department of Pathology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)
- Department of Medical Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)
Purpose: Postmastectomy radiation therapy (PMRT) has been shown to benefit breast cancer patients with 1 to 3 positive lymph nodes, but it is unclear how modern changes in management have affected the benefits of PMRT. Methods and Materials: We retrospectively analyzed the locoregional recurrence (LRR) rates in 1027 patients with T1,2 breast cancer with 1 to 3 positive lymph nodes treated with mastectomy and adjuvant chemotherapy with or without PMRT during an early era (1978-1997) and a later era (2000-2007). These eras were selected because they represented periods before and after the routine use of sentinel lymph node surgery, taxane chemotherapy, and aromatase inhibitors. Results: 19% of 505 patients treated in the early era and 25% of the 522 patients in the later era received PMRT. Patients who received PMRT had significantly higher-risk disease features. PMRT reduced the rate of LRR in the early era cohort, with 5-year rates of 9.5% without PMRT and 3.4% with PMRT (log-rank P=.028) and 15-year rates 14.5% versus 6.1%, respectively; (Cox regression analysis: adjusted hazard ratio [AHR] 0.37, P=.035). However, PMRT did not appear to benefit patients treated in the later cohort, with 5-year LRR rates of 2.8% without PMRT and 4.2% with PMRT (P=.48; Cox analysis: AHR 1.41, P=.48). The most significant factor predictive of LRR for the patients who did not receive PMRT was the era in which the patient was treated (AHR 0.35 for later era, P<.001). Conclusion: The risk of LRR for patients with T1,2 breast cancer with 1 to 3 positive lymph nodes treated with mastectomy and systemic treatment is highly dependent on the era of treatment. Modern treatment advances and the selected use of PMRT for those with high-risk features have allowed for identification of a cohort at very low risk for LRR without PMRT.
- OSTI ID:
- 22416587
- Journal Information:
- International Journal of Radiation Oncology, Biology and Physics, Journal Name: International Journal of Radiation Oncology, Biology and Physics Journal Issue: 2 Vol. 89; ISSN IOBPD3; ISSN 0360-3016
- Country of Publication:
- United States
- Language:
- English
Similar Records
Locoregional Failure in Early-Stage Breast Cancer Patients Treated With Radical Mastectomy and Adjuvant Systemic Therapy: Which Patients Benefit From Postmastectomy Irradiation?
Patterns and Risk Factors of Locoregional Recurrence in T1-T2 Node Negative Breast Cancer Patients Treated With Mastectomy: Implications for Postmastectomy Radiotherapy