Combination chemotherapy with gemcitabine and irinotecan in patients with previously treated carcinoma of an unknown primary siteThe following institutions are Minnie Pearl Cancer Research Network Participating Sites: Tennessee Oncology, PLLC (Nashville, TN); Wellstar Cancer Research (Marietta, GA); Consultants in Blood Disorders & Cancer (Louisville, KY); Graves‐Gilbert Clinic (Bowling Green, KY); Grand Rapids CCOP (Grand Rapids, MI); Upstate Carolina CCOP (Spartanburg, SC); Northeast Georgia Medical Center (Gainesville, GA); King's Daughters' Medical Center (Ashland, KY); Pheobe Cancer Center (Albany, GA); The Reading Hospital and Medical Center (Reading, PA); and Montana Cancer Specialists (Missoula, MT).: A Minnie Pearl Cancer Research Network Phase II trial

The current study was performed to evaluate the activity of combination chemotherapy with gemcitabine and irinotecan in patients with previously treated carcinoma of an unknown primary site.Patients with carcinoma of an unknown primary site who had received one previous chemotherapy regimen were eligible for this study. All patients received gemcitabine at a dose of 1000mg/m2 intravenously (i.v.) and irinotecan at a dose of 100 mg/m2 i.v. on Days 1 and 8; treatment courses were repeated every 21 days. Patients were evaluated for response after completing two courses of treatment; responders/stable patients continued treatment for a recommended six courses.Forty patients entered this multicenter, community‐based Phase II trial between September 2000 and July 2003. Four of these 40 patients (10%) achieved objective responses (a partial response in 3 patients and a complete response in 1 patient). An additional 17 patients (43%) had stable disease/minor response at first reevaluation; 7 of these patients (18%) remained stable for longer than 6 months. The median survival for the entire group was 4.5 months, with 1‐year and 2‐year survival rates of 25% and 13%, respectively. The treatment was well tolerated by most patients. Neutropenia was the most common Grade 3/4 toxicity (according to the National Cancer Institute Common Toxicity Criteria, version 3.0) (occurring in 36% of patients). Myelosuppression‐related complications were uncommon, as were severe nonhematologic toxicities.The combination of gemcitabine and irinotecan has modest activity and is well tolerated in patients with recurrent/refractory carcinoma of an unknown primary site. Treatment‐related toxicity, particularly myelosuppression, appears to be less severe than toxicity produced by the taxane and platinum regimens frequently used in the first‐line therapy of these patients. Evaluation of the gemcitabine and irinotecan combination as first‐line therapy is indicated. Cancer 2005. © 2005 American Cancer Society.