Role of tumor immunity in ovarian cancer

Antigens associated with ovarian cancer tissue have been identified by the use of heteroantisera. It has also been reported that lymphocytes from patients with ovarian cancer responded to phytohemagglutinin (PHA) and keyhole-limpet hemocyanin (KLH) but had failed to respond to autologous tumor extracts. In our series, pretreatment sera from 37 patients with stage III and IV ovarian cancer failed to react with ovarian cancer antigen preparations. After therapy, serum from only three patients was reactive: all three patients were treated by chemoimmunotherapy. Preliminary data from this clinical trial for treating stage III and IV ovarian cancer with chemotherapy, immunotherapy, or combined chemoimmunotherapy show that survival of patients treated by chemotherapy or immunotherapy corresponded to that of nonresponders to L-PAM therapy as described in another study. Interestingly, combined chemoimmunotherapy produced a survival curve depicting significant improvement, similar to that for the responders to L-PAM therapy reported in that study.