Combination of cyclophosphamide, adriamycin and platinum (CAP) versus 5-fluorouracil, adriamycin and cyclophosphamide (FAC) as primary treatment in metastatic breast cancer: results of a prospective randomized study.

Based on favorable results we reported earlier with the CAP regimen in breast cancer (CAP vs CMFVP), the present study compared the CAP with the FAC regimen, which is so far one of the most active adriamycin containing chemotherapy regimens in breast cancer. The aim of the study was to find the optimal first line treatment and possibly evaluate the role of cis platinum in breast cancer chemotherapy. The CAP schedule consisted of cyclophosphamide 200 mg/m2 i.v. days 1, 3 and 5, adriamycin 40 mg/m2 i.v. day 1, and platinum 30 mg/m2 i.v. day 1, 3 and 5. The FAC schedule included 5-FU 500 mg/m2 days 1 and 8, adriamycin 50 mg/m2 day 1, and cyclophosphamide 500 mg/m2 day 1. One hundred and twenty-six previously untreated patients received greater than 2 cycles and were evaluated. In the CAP arm 15 complete (26%) and 24 partial remissions were observed, resulting in a 67% overall response rate (39/58). The response in soft tissue and visceral organs was notable (78% - 22/28, 71% - 15/21) with an important complete response rate (32%). In the FAC arm there was an overall response in 41% (28/68) of patients, with 8 complete (12%) and 20 partial responses. The difference in overall response, complete response, and response in soft tissue and visceral organs, was statistically significant in favor of the CAP arm (P less than 0.005). Concerning bone metastases there was no difference between the two schedules in response rate, nor in the median remission duration (CAP 11, FAC 10 months). In spite of a somewhat longer median survival in the CAP group, the difference (13 months vs 9 months) was not statistically significant (P = 0.10). Toxicity was moderate and tolerable in both regimens with more pronounced myelosuppression and vomiting in the CAP group. Compared with the FAC schedule the platinum containing combination chemotherapy (CAP) showed higher antitumor activity with no reflection on remission duration and survival.