The use of treosulfan and gemcitabine in the treatment of platinum-resistant ovarian cancer.

The combination of treosulfan and gemcitabine (TG) has been shown to have activity in ovarian cancer. These two agents are thought to be synergistic, with gemcitabine causing the persistence of treosulfan-induced DNA crosslinks. This study aimed to investigate the response rates, survival and toxicity in patients with platinum-resistant ovarian cancer treated with TG. A retrospective case note review of the patients treated with TG was performed in one cancer centre between May 1st, 2000 and November 1st, 2005. Estimates of cumulative survival were obtained using the Kaplan-Meier method. Forty-nine patients were identified; median age at diagnosis was 55 years (range, 31-72) and the median follow-up was 45.1 months (range, 12.2-118.3). TG was used as second-, third-, fourth- and fifth-line chemotherapy in 15, 19, 13 and 2 patients, respectively. Fifteen patients (30.6%) had stable disease; 25 (51%), a partial response; 1 (2%), a complete response and 8 (16.3%) had progressive disease. Median survival following diagnosis was 45.1 months and the median relapse-free survival was 12 months. The median survival time from the start of TG was 13.7 months with a relapse-free survival of 6.3 months. The median number of cycles given was 7. The most common toxicity recorded was myelosuppression. There were no treatment-related deaths. TG chemotherapy produced favourable response rates in a heavily pre-treated group of patients with platinum-resistant epithelial ovarian cancer. This doublet warrants further investigation in a phase III trial setting.