Indications for postmastectomy radiotherapy in breast cancer patients with 1 -3 positive axillary nodes / 中华放射肿瘤学杂志

ABSTRACT

Objective To analyze the prognosis of T1-T2 stage breast cancer with 1 -3 positive axillary nodes after mastectomy, and to explore a subgroup of patients who could benefit from adjuvant radiotherapy. Methods In the retrospective study of 412 eligible patients, survival analysis was performed using the Kaplan-Meier method. Univariate and multivariate analyses were performed using the Log-rank method and Cox regression analysis, respectively. Results The follow-up rate was 98. 7%. 215 and 41patients were followed up for 5 and 10 years,respectively. The 5-and 10-year overall survival (OS) rate was 90. 0% and 81.3%, respectively. The 5-and 10-year locoregional recurrence (LRR) rate was 10. 7% and 18. 6%, respectively. In univariate analysis, T2 statging, more than one positive node, hormone receptornegative ( ER&PR-negative), ratio of positive lymph nodes (LNR) ＞ 25%, Her-2 positive, no hormonal therapy were associated with a significantly higher rate of LRR. T2 staging, more than one positive node,hormone receptor-negative were the risk factors for LRR with statistical significance in the multivariate analysis. Basing on these 3 risk factors, the high-risk group (with 2 -3 factors) had a 10-year LRR rate of 36. 9% compared with 3.9% in the low-risk group ( with 0 - 1 factors;x2 =20. 64,P =0. 000). The 5-year and 10-year distant metastasis (DM) rate was 12.9% and 24. 5%, respectively. LRR, and LNR ＞25%were statistically significant predictors of DM in the multivariate analysis. The 5-year DM rate for patients with LRR was 36. 6% compared with 9. 7% without LRR (x2 = 16. 34,P =0. 000). The 5-year OS rate for patients with LRR was 69. 9% compared with 92. 9% without LRR ( x2 = 20. 79, P = 0. 000). LRR was associated with a higher risk of distant metastasis and worse survival. Conclusions LRR after mastectomy has a significant impact on the outcome of patients with T1 -T2 breast cancer and 1 - 3 positive axillary nodes.Patients who have 2 -3 risk factors might benefit from radiotherapy.