Patients receive interferon alfa subcutaneously on days 1, 3, 5, and 7; paclitaxel intraperitoneally (IP) on day 4 or topotecan IP on day 6; and 177Lu-CC49 IP on day 6. Treatment continues every 6 weeks for 2 courses in the absence of disease progression or unacceptable toxicity. Cohorts of 3-5 patients receive escalating doses of paclitaxel and decreasing doses of 177Lu-CC49 until the maximum tolerated dose (MTD) is determined. The MTD is defined as the dose preceding that at which 3 of 5 patients experience dose limiting toxicity. Once the MTD of paclitaxel is determined, the dose of 177Lu-CC49 is escalated. Once the MTD of 177Lu-CC49 is determined, 90Y-CC49 is substituted. The MTD of 90Y-CC49 is then determined when administered with paclitaxel. Topotecan is then substituted for paclitaxel (administered with the MTD of 177Lu-CC49 and interferon alfa only) and escalated until the MTD is determined. Patients are followed at 6 weeks and then every 3 months for 1 year.