A phase II study to evaluate the efficacy and toxicity of oxaliplatin in combination with gemcitabine in carcinoma of unknown primary

Background Preclinical and clinical data suggest synergy for gemcitabine and oxaliplatin. These agents were tested in several known cancers that also comprise the common carcinoma of unknown primary (CUP) subtypes; namely, lung and pancreaticobiliary profiles. Methods The study enrolled 29 patients of whom 28 patients were eligible for treatment. Gemcitabine was given at 1,000 mg/m 2 as a fixed dose rate infusion and oxaliplatin was infused at 100 mg/m 2 every 2 weeks with restaging performed after 3 cycles at 6 weeks. Results The study reported one complete response (CR) (4%), 6 patients with a partial response (PR) (25%), and 13 with stable disease (SD) (54%); and 4 patients had progressive disease (PD) (17%) on restaging. Median overall survival (OS) and progression-free survival were 12.8 months (95% confidence interval [CI] 8.5–18.5) and 3.1 months (95% CI 1.7–6), respectively. The 1-year OS was 54%. The most common grade 3 toxicities were nausea (22%), vomiting (15%), and fatigue (11%). There were no grade 4 toxicities. This study was closed early as we moved from an empiric therapy platform to a more individualized approach. Conclusions Gemcitabine and oxaliplatin is a well-tolerated regimen in CUP with similar outcomes to previously documented CUP studies. In selected good performance status patients this combination may serve as a first-line doublet chemotherapy option for CUP patients (clinicaltrials.gov ID:NCT00353145).