Local recurrence in breast cancer after conservative surgery: Timing of radiotherapy and sequencing of chemotherapy

Background: A randomized trial was conducted to determine (a) the role of radiotherapy and chemotherapy on local control and (b) to determine the timing of radiotherapy for early-stage breast cancer. Materials and Methods: Five hundred and ninety patients were treated with both conservative surgery and radiotherapy (group A). The average time interval between surgery and radiation was 90 days for 452 patients and over 90 days for 138 patients. One hundred and ninety-four patients underwent adjuvant therapy based on CMF regimens (group B). Results: Among 396 patients of group A, 8.1% had local failure; we observed 7.2% local recurrences in 363 patients who received therapy before 90 days and 18.2% in patients who received therapy after 90 days. Among patients of group B, 7.7% had local failure; for patients who underwent radiotherapy before 90 days, the local recurrence rate was 6.6%, compared with 12.3% for patients who underwent therapy more than 90 days after surgery. Conclusion: In patients who are eligible to receive chemotherapy, it is possible to administer radiotherapy after systemic treatment, while in patients who have to be treated with radiotherapy more then 90 days after breast surgery, chemotherapy can reduce the local failure rate.