Silicone prostheses and anti-tumor immunity: an in-vitro rat study.

We believe we have demonstrated that there is no difference in the immune responsiveness in normal animals which undergo sham surgery (as compared to those unoperated). With the addition of a simple placement of a silicone prosthesis, there was an increase in the lymphocyte cytotoxicity--but this was equalized by a blocking effect at both the target cell and the lymphocyte levels. This response appeared to be of short duration. The presence of tumor, as previously documented produces an increase in lymphocyte cytotoxicity with a concomitant increase in the target cell and the lymphocyte blocking effect. Importantly, we found no significant difference in the immune response when prostheses were placed as an adjunct to surgical excision of transplanted tumors in this rat model.