Adjuvant radiotherapy on older and oldest breast cancer patients after conservative surgery: a retrospective analysis.

Purpose of this study was to evaluate the impact of adjuvant radiotherapy, in terms of feasibility and activity, in women aged ≥ 75 years with early (stage) breast cancer. From January 2000 to December 2007, 131 consecutive patients aged 75 years or older received adjuvant radiotherapy after breast conserving surgery. Eighty-two patients received radiotherapy in combination with 5 years of hormone therapy with tamoxifen or aromatase inhibitor. Thirty out of 131 received chemotherapy. Variables considered were age, stage, co-morbidity, performance status, radiation dose (boost), hormone therapy and chemotherapy. The mean age was 78.3 years (range 75-88 years). A total of 19.1% of the patients had no co-morbidity, 57.38% mild, 19.8% moderate, and 3.8% had severe co-morbidities. All patients but one completed the planned radiation schedule. At a median follow-up of 56 months, the 5-year overall survival rate was 78.8%. There was a better survival for patients with no or mild co-morbidities (p<0.0001). The disease-free survival at 5 years was 89.6%. No difference in acute and late toxicity rates was found between patients with different ACE-27 (Adult Comorbidity Evaluation-27) indexes and for different age. We conclude that compliance with adjuvant radiotherapy is good and rate of toxicity is acceptable in elderly patients. Patients with no or mild co-morbidities have a significantly better survival. Increasing severity of co-morbidity may sufficiently shorten remaining life expectancy to cancel gains with adjuvant radiotherapy. Further prospective trials are needed to confirm these results.