Irradiated Cells from Autologous Tumor Cell Lines as Patient-Specific Vaccine Therapy in 125 Patients with Metastatic Cancer: Induction of Delayed-Type Hypersensitivity to Autologous Tumor is Associated with Improved Survival

Objective: We established short-term cultures of pure tumor cells for use as autologous tumor cell vaccines in an effort to study the effects of patient-specific immunotherapy. Patients and Methods: Surgically resected fresh tumor was obtained from patients with metastatic cancer. Successful tumor cell lines (5 × 107) were expanded to 108 cells, irradiated, and cryopreserved for clinical use. Following a baseline test of delayed-type hypersensitivity (DTH) to an i.d. injection of 106 irradiated autologous tumor cells, patients received 3 weekly s.c. injections of 107 cells, had a repeat DTH test at week-4, then received monthly vaccinations for 5 months. A positive DTH test was defined as ≥ 10 mm induration; survival was determined from the first DTH test. Results: Short-term cell lines were successfully established for 299/695 patients (43%). Vaccines were prepared for 231 patients, 142 of whom were treated, and 125 had a baseline DTH test recorded. Median follow up at the time of analysis was greater th...