Factors influencing loco-regional relapse in older breast cancer patients treated with tumour resection and tamoxifen.

In breast cancer patients (≥70 years), tumour resection plus tamoxifen (T + T) has a higher loco-regional relapse (LR) rate than mastectomy. This study examines factors influencing local recurrence in these cases.Clinical records of 71 patients aged ≥70 years, randomised to the T + T arm of 2 randomised trials were reviewed. Cox Proportional Hazards model was used to determine the most significant variables.After 15-years follow-up, LR relapse occurred in 29/71, of whom 5 had synchronous metastatic disease. Most tumours recurred in the index quadrant. Subsequently 21/24 patients with loco-regional recurrence only had salvage mastectomy. Three variables significantly predicted LR: lympho-vascular invasion (LVI) (HR [95% CI]: 11.18 [4.47, 27.95], p < 0.01), ER negative status (HR [95% CI]: 0.27 [0.10, 0.72] p = 0.01), and tumour necrosis (HR [95% CI]: 2.65 [1.10, 6.37], p = 0.03). Final margin status was not associated with LR.Tumour resection + Tamoxifen in older patients results in long-term local control in the majority with most loco-regional failures being salvageable. Risk factors for LR are lympho-vascular invasion, ER status and tumour necrosis. Negative tumour excision margins did not significantly change local outcome in the absence of radiotherapy. In these older patients LVI significantly reduced survival time.