Impact of relative dose intensity in gemcitabine–cisplatin chemotherapy for metastatic urothelial carcinoma

OBJECTIVES: To evaluate the impact of relative dose intensity for gemcitabine–cisplatin chemotherapy in patients with metastatic urothelial carcinoma. METHODS: We retrospectively reviewed the medical records of 18 patients with metastatic urothelial carcinoma, who received gemcitabine–cisplatin regimen as the first-line chemotherapy between 2009 and 2015. The doses of gemcitabine and cisplatin were reduced or the intervals between treatment cycles were prolonged according to the treatment efficacy and adverse events during the first and second cycles. The individually optimal relative dose intensity was set as the actual dose per the standard dose in the first and second cycles. From the third course onward, patients received the gemcitabine–cisplatin chemotherapy with the same relative dose intensity. Overall survival was compared with the groups according to the value of relative dose intensity. RESULTS: The median age was 72.5 (range, 56–79) years and 15 men and 3 women were enrolled in the study. The median number of cycles of first-line gemcitabine–cisplatin chemotherapy was 8 (range, 2–17), and the median survival time from initiation of first-line chemotherapy was 20.1 (range, 3.5–32.8) months. The total median relative dose intensity of gemcitabine–cisplatin chemotherapy was 56.1%. The median survival time of 10 patients in the group with the relative dose intensity of less than 60% was significantly longer than that of 8 patients in the group with the relative dose intensity of more than 60% (19.2 and 11.0 months, respectively, p = 0.04). CONCLUSION: Individual low relative dose intensity management in the first-line gemcitabine–cisplatin chemotherapy may be an acceptable option for patients with metastatic urothelial carcinoma.