Prospective multicenter phase II study of gemcitabine plus cisplatin in patients with unresectable gallbladder cancer

To evaluate the efficacy and safety of gemcitabine plus cisplatin in Japanese patients with unresectable gallbladder cancer (GBC).

Chemo-naïve patients with histologically proven unresectable GBC were enrolled in this study. The patients received gemcitabine (1000 mg/m²) and cisplatin (25 mg/m²) on days 1 and 8, every 21 days. A response assessment was done by CT scan every 4 weeks. The primary end points were to determine the response rates [RR; complete response (CR) + partial response (PR)] and the disease control rate [DCR; CR + PR + stable disease (SD)]. The secondary end points were to evaluate toxicity, progression-free survival (PFS), and overall survival (OS).

From March 2012 to February 2015, 14 patients from seven different institutions were enrolled in the study, and 13 cases were evaluable for assessment. Eleven cases (84.6%) had distant metastases, and 8 cases (61.5%) had obstructive jaundice. There was no CR, 1 PR (7.7%), 11 SD (84.6%), and 1 progressive disease (PD) (7.7%). The RR was 7.7%, whereas the DCR was 92.3%. The median PFS was 3.1 months, the median OS was 6.2 months, and the one-year survival rate was 0%. Grade 3 hematologic toxicity was observed in three cases (23%), but all of them recovered upon drug withdrawal, and there was no treatment-related death.

Although gemcitabine plus cisplatin has a high DCR (92.3%) and relatively low toxicity, the RR is less than 10%, and development of new therapies is desired for the treatment of unresectable GBC.