Use of the monoclonal antibody anti-HER2 trastuzumab in the treatment of metastatic breast cancer: a cost-effectiveness analysis.

Background: This open controlled prospective study aimed at evaluating the medical and economical impact of first line chemotherapy for metastatic breast cancer (MBC). Patients and Methods: Two groups of HER +++ MBC patients were compared: 26 were treated by a combination of trastuzumab and paclitaxel in 4 “prescriber” centers (group A) and 19 patients were treated by any chemotherapy without addition of trastuzumab, in 6 control centers (group B). The cost of chemotherapy and related hospitalizations was taken into account during the first 8 cycles. Results: Forty-five patients, mean age 51 years have been included. The objective response rate was significantly higher in group A (42% vs. 6%, P = 0.036). The median overall survival was 17 months longer in the group A (29 vs. 12 months). The median progression free survival rate was 12.2 months longer in the group A (19 vs. 7 months). The 1-year survival rate was 85% in the group A and 47% in the group B. The mean overall care cost was 33.271 € per patient in group A versus 11.191 € per patient in group B. The additional cost per saved year of life expressed as the incremental cost-effectiveness ratio is 15.370 € 2002. Conclusion: The related additional cost seems affordable for an European health care system and justifies the recommendation for its use in the subpopulation overexpressing HER2.