Matched case-control survival analysis of older chinese breast cancer patients treated with surgery or primary endocrine therapy

Abstract

Background: Primary endocrine therapy (PET) has been used as an alternative to primary surgery for elderly with estrogen receptor (ER) positive breast tumors. Such practices are less commonly performed in Asian countries and the response to PET in Chinese cohort is still lacking. This study aims to compare the clinical outcome of PET to primary surgery.

Patients and methods: Medical records of Chinese patients aged 70 and above with stage I to III, ER positive breast cancer treated at a University affiliated tertiary hospital from 2008 to 2017 were reviewed. Excluding those with extreme comorbidity, a one-to-one case-control survival analysis of patients treated with PET or primary operation was performed, using propensity score case-match analysis to adjust for confounding factors.

Results: 292 patients fulfilled the inclusion criteria during the study period. 209 patients received primary operation, whereas 83 patients received PET. Excluding those with extreme comorbidity, a one-to-one matching was performed, and the dataset was stratified into survival time within 0-5 years and beyond 5 years. Both groups had similar survival within 0-5 years (p = 0.63). The survival curves diverged beyond 5 years, with a significantly better outcome in patients operated than those treated with PET (p = 0.0029).

Conclusions: For frail older patients with limited life expectancy, PET may be appropriate since equivalent survival can be achieved for PET with or without surgery. Those patients with longer life expectancy may gain survival benefits from local treatment. A comprehensive geriatric assessment is useful to predict the survival probability and guide the optimal treatment.

Keywords: Breast cancer; case-control matching; older chinese patients; primary endocrine therapy; surgery.