Expression and modulation of class I and class II histocompatibility leukocyte antigens on human soft tissue sarcomas

Phase I/II trial of autologous tumor cell line-derived vaccines for recurrent or metastatic sarcomas

AIM

We previously reported the laboratory methodology for producing patient-specific irradiated autologous tumor-cell products derived from short-term cultured tumor cells. We attempted to determine the feasibility, safety, and clinical effects of autologous tumor vaccine-derived sarcomas.

PATIENTS AND METHODS

Efforts were made to establish tumor cell lines in tissue culture with expansion to 100 million cells for patients who were candidates for therapy. Cells were irradiated and cryopreserved in aliquots of 10 million cells for subcutaneous (s.c.) injections, once a week for 3 weeks, then once a month for 5 months.

RESULTS

Efforts were made to establish short-term tumor cell lines from 86 fresh sarcoma specimens (10 primary, 14 recurrent, and 62 metastatic). Initial growth was successful for 48 patients (56%), and cultures were expanded for 36 patients, with 25 patients treated. There were 23 evaluable patients, including 12 women and 11 men, with a median age of 52 years and a range from 16-79 years. Vaccine therapy was well tolerated. Delayed-type hypersensitivity (DTH) tests to irradiated tumor cells were positive in 0 of 20 patients tested at baseline, but converted to positive after 3 weekly vaccinations in 8 of 16 patients who were retested. Median survival for the 8 DTH converters was 16.6 months versus 8.2 months for the 8 responders whose tumor DTH test remained negative, and 6.0 months for the 7 patients who were not tested. No objective responses were recorded among 12 evaluable patients with measurable disease; 10 patients have survived more than 1 year.

CONCLUSIONS

This approach is feasible, well tolerated, and the resulting DTH conversion rate is of interest. Patients with minimal tumor burden would be preferred for further future testing.