Gemcitabine and Irinotecan in Treating Patients With Cancer of Unknown Primary

OBJECTIVES:

Primary

• Determine the response rate in patients with carcinoma of unknown primary when treated with gemcitabine and irinotecan.
• Determine the adverse event profile and tolerability of this regimen, based on the presence or absence of the UGT1A1*28 polymorphism, in these patients. (Cohort I closed to accrual 11/17/05)
• Determine the adverse event profile and tolerability of this regimen. (Cohort II)

Secondary

• Determine the time to progression and overall survival of patients treated with this regimen.
• Correlate patterns of immunohistochemical staining with response in patients treated with this regimen.
• Correlate variation in multiple different genes, whose protein products are involved in the uptake, metabolism, and distribution of these drugs, with clinical outcomes, in terms of response and toxicity, in these patients.
• Determine primary origin of cancer of unknown primary samples by completing a 92-gene RT-PCR cancer classification assay.
• Determine whether the 92-gene assay results are correlated with clinical response to gemcitabine and irinotecan.

OUTLINE:

• Cohort I (closed to accrual 11/17/05): Patients receive gemcitabine IV over 30 minutes and irinotecan IV over 90 minutes on days 1, 8, 15, and 22. Irinotecan dose may be escalated or de-escalated after course 1 depending on toxicity. Courses repeat every 6 weeks in the absence of disease progression or unacceptable toxicity.
• Cohort II: Patients receive gemcitabine IV over 30 minutes and irinotecan IV over 90 minutes on days 1, 8, and 15. Courses repeat every 4 weeks in the absence of disease progression or unacceptable toxicity.

Patients are followed every 3 months for 2 years.