We treated 64 patients with metastatic melanoma using a melanoma vaccine preceded by low-dose cyclophosphamide (CY), and monitored immunologic effects and antitumor activity. On day 0, the patients were given CY 300 mg/m2 intravenously. Three days later, they were injected intradermally with vaccine consisting of 10 to 25 x 10(6) autologous, enzymatically dissociated, cryopreserved, irradiated (25 Gy) tumor cells mixed with bacillus Calmette-Guérin (BCG). This treatment sequence was repeated every 28 days. Of 40 assessable patients with measurable metastases, five had responses, four complete and one partial, with a median duration of 10 months (7 to 84+ months). In six additional patients, we observed an antitumor response that seems to be peculiar to this vaccine therapy: the regression of metastatic lesions that appeared after the immunotherapy was begun. Delayed-type hypersensitivity (DTH) to autologous, mechanically dissociated melanoma cells that had not been exposed to extraneous antigens, such as enzymes or fetal calf serum, increased significantly following immunotherapy (day 0 v day 49, P less than .001; day 0 v day 161, P less than .001; day 0 v day 217, P = .021). Antitumor responses to the vaccine were strongly associated with DTH, as indicated by three observations: (1) eight of 10 patients who exhibited tumor regression had positive DTH, (2) in postsurgical adjuvant patients, there was a highly significant linear relationship (P less than .001) between the intensity of DTH to autologous melanoma cells and the time to recurrence of tumor, and (3) nine patients who developed DTH to the autologous melanoma cells in their original vaccine developed new metastases that failed to elicit DTH or elicited a much smaller response. In three cases, we were able to excise regressing tumors for histologic examination; such tumors were characterized by an intense infiltration of lymphocytes. This demonstration that an immune response to melanoma-associated antigens can be elicited in cancer-bearing patients provides some basis for optimism about the prospects for developing active immunotherapy that has practical therapeutic value.

This study underscores the importance of the immunopharmacology of the autologous, DNP-modified vaccine and may be relevant to other cancer vaccine technologies.

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Uveal melanoma is the most common primary intraocular malignancy in adults and the liver is the most common site for systemic metastases. We conducted a phase II clinical trial for patients with hepatic metastases from uveal melanoma using chemoembolization of the hepatic artery with 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) dissolved in ethiodized oil. Gelatin sponge particles were used as a transiently occlusive agent. The responses in hepatic metastases, overall survival, time to progression and side-effects related to chemoembolization were evaluated. Thirty patients were enrolled. Twenty-four patients completed at least one treatment to all targeted liver metastases and were evaluable for hepatic response. Eighteen of these 24 patients experienced regression or stabilization of hepatic metastases for at least 6 weeks (one complete response in hepatic metastases; four partial responses; 13 stable disease). One of the 13 patients with stable disease was rendered free of disease by surgical removal of metastases after chemoembolization (surgical complete response). The overall response rates (complete and partial responses) for intention-to-treat patients and for patients who were evaluable for response were 16.7 and 20.4%, respectively. The median overall survival of the entire intention-to-treat group of patients was 5.2 months (range, 0.1-27.6 months), for patients with complete or partial response in hepatic metastases 21.9 months (range, 7.4-27.6 months), for patients with stable disease 8.7 months (range, 2.9-14.4 months) and for patients with progressive disease 3.3 months (range, 1.6-5.6 months). Importantly, 13 of the 18 patients who achieved complete response, partial response or stable disease subsequently developed progression of extrahepatic metastases with control of hepatic metastases. Chemoembolization with BCNU is a useful palliative treatment for the control of hepatic metastases in uveal melanoma patients. However, progression in extrahepatic sites after stabilization of hepatic metastases requires further improvement in the therapeutic approach to this disease.