OUTLINE: This is a dose escalation study. Patients receive indium In III pentetreotide (OctreoScan) IV on day 1. Imaging is conducted on days 3 and 6. Treatment continues weekly for a total of 4 courses in the absence of disease progression or unacceptable toxicity. Cohorts of at least 3 patients receive escalating doses of OctreoScan until the maximum tolerated dose (MTD) is determined. The MTD is defined as the dose preceding that at which 2 of 3 patients experience dose limiting toxicities. Patients are followed every 3 months for the first year, then every 6 months thereafter.