[Simultaneous radiochemotherapy in recurrent and metastatic breast neoplasm. Clinical experience].

Background: To improve the quality of life for patients with recurrent and metastatic breast cancer, palliation of pain, skin and soft tissue metastases and complicating lymph node relapses are mandatory. Toxicity and efficacy of 2 simultaneous radiochemotherapy regimens was tested in this study.
Patients and Methods: From October 1989 to March 1993, 48 patients with locoregional relapse of breast carcinoma after primary mastectomy and no option for curative resection were entered in the study. Seventeen patients had additional distant metastases. Two different radiochemotherapy regimens were applied: Group A (28 patients) received a "split course" radiotherapy within 10 weeks (1.8 to 2 Gy single dose) on day 1 to 12, 29 to 40 and 57 to 68 up to a total dose of 54 Gy. Chemotherapy with 5-FU, methotrexate and cyclophosphamide was applied simultaneously with radiation. After the second and fourth week the treatment was interrupted for 2 weeks. Group B (20 patients) received "conventional" radiotherapy over 6 weeks with 1.8 to 2 Gy single and 54 Gy total dose. 5-FU and mitomycin C was applied in the first and fifth week of radiotherapy. Treatment toxicity was analyzed in 48 patients, while treatment efficacy was assessed in 44 patients with a minimum follow-up of at least 1 year.
Results: Overall treatment response (CR+PR) was 82% in group A (CR 21%). Five of 28 patients developed toxicities of grade 3 to 4 (EORTC/RTOG/WHO). The overall response rate in group B was 87% (CR 19%). In this group 6 of 20 patients experienced toxicities of grade 3 to 4. In both groups, the local response rate was remarkably reduced in patients with additional visceral metastases.
Conclusions: Both treatment concepts achieved similar response rates. Group B patients experienced a higher toxicity rate, but treatment duration was considerably shorter. The local response rate correlated well with the extent of systemic metastatic disease.