Postmastectomy radiotherapy in patients with T1-2N1 breast cancer: a single center experience and a meta-analysis

J Cancer Res Clin Oncol. 2023 Sep;149(12):9979-9990. doi: 10.1007/s00432-023-04908-7. Epub 2023 May 31.

Abstract

Purpose: Postmastectomy radiotherapy (PMRT) in patients with T1-2N1 breast cancer is still controversial. This study was to evaluate the survival prognosis of T1-2N1 patients with or without PMRT.

Patients and methods: From January 2006 to May 2017, 2606 female breast cancer patients underwent mastectomy in our medical center, among whom 402 patients of T1-2N1 stage with or without PMRT were finally analyzed. The median follow-up duration was 59.5 months. The primary endpoint was overall survival (OS). The secondary endpoint was disease-free survival (DFS).

Results: In the study of our center, no statistically significant difference was observed between the T1-2N1 PMRT and non-PMRT subgroups for the 5-year OS (94.4% vs 95.4%, p = 0.667) and DFS (90.1% vs. 91.1%, p = 0.798). By the date of the last follow-up, 8.96% (n = 36) of the patients experienced any recurrence. Univariate analysis revealed that PMRT was not a prognostic factor for either OS (p = 0.667) or DFS (p = 0.798) in T1-2N1 patients. We then did a meta-analysis on the current treatment patterns, in which 2606 PMRT and 4281 non-PMRT T1-2N1 breast cancer patients with mastectomy were included. The meta-analysis showed that PMRT didn't improve the OS of the patients (HR = 0.85, p = 0.11), but patients with PMRT had better DFS than those in the non-PMRT group (HR = 0.62, p < 0.001).

Conclusion: PMRT did not affect the survival of T1-2N1 breast cancer patients who underwent mastectomy, suggesting that radiotherapy may be safely omitted for them.

Keywords: Breast cancer; Disease-free survival; Overall survival; Postmastectomy radiotherapy.

Publication types

  • Meta-Analysis

MeSH terms

  • Breast Neoplasms* / pathology
  • Breast Neoplasms* / radiotherapy
  • Breast Neoplasms* / surgery
  • Female
  • Humans
  • Mastectomy
  • Neoplasm Recurrence, Local / pathology
  • Neoplasm Staging
  • Radiotherapy, Adjuvant
  • Retrospective Studies