Concurrent chemoradiotherapy in adjuvant treatment of breast cancer.

Background: The optimal sequencing of chemotherapy and radiotherapy after breast surgery was largely studied but remains controversial. Concurrent chemo-radiotherapy is a valuable method for adjuvant treatment of breast cancer which is under ongoing research program in our hospital. We are evaluating the feasibility of the concomitant use of chemotherapy retrospectively.

Methods: Two hundred forty four women having breast cancer were investigated in a retrospective study. All patients were either treated by radical surgery or breast conservative surgery. The study compares two adjuvant treatments associating concomitant chemotherapy and radiotherapy. In the first group (group A) the patients were treated by chemotherapy and radiotherapy in concomitant way using anthracycline (n = 110). In the second group (group B) the patients were treated by chemotherapy and radiotherapy in concomitant way using CMF treatment (n = 134). Chemotherapy was administered in six cycles, one each 3 weeks. Radiotherapy delivered a radiation dose of 50 Gy on the whole breast (or on the external wall) and/or on the lymphatic region. The Kaplan-Meier method was used to estimate the rates of disease free survival, loco-regional recurrence-free survival and overall survival. The Pearson Khi2 test was used to analyse the homogeneity between the two groups. The log-rank test was used to evaluate the differences between the two groups A and B.

Results: After 76.4 months median follow-up (65.3 months mean follow up), only one patient relapsed to loco-regional breast cancer when the treatment was based on anthracycline. However, 8 patients relapsed to loco-regional breast cancer when the treatment was based on CMF. In the anthracycline group, the disease free survival after 5 years, was 80.4% compared to 76.4% in the CMF group (Log-rank test: p = 0.136). The overall survival after 5 years was 82.5% and 81.1% in the anthracycline and CMF groups respectively (Log-rank test: p = 0.428). The loco-regional free survival at 5 years was equal to 98.6% in group A and 94% in group B (Log-rank test: p = 0,033). The rate of grade II and grade III anaemia was 13.9% and 6.7% in anthracycline group and CMF group respectively (Khi2-test: p = 0.009). The rate of grade II and grade III skin dermatitis toxicity was 4.5% in the group A and 0% in the group B (Khi2-test: p = 0.013).

Conclusion: From the 5 years retrospective investigation we showed similar disease free survival and overall survival in the two concurrent chemo-radiotherapy treatments based on anthracycline and CMF. However in the loco-regional breast cancer the treatment based on anthracycline was significantly better than that of the treatment based on CMF. There was more haematological and skin dermatitis toxicity in the anthracycline group.