Cellular Immunity to Autologous Breast Cancer and RIII-Murine Mammary Tumor Virus Preparations1

Cell-mediated immunity (CMI) to autologous breast can cer tissue was measured by means of skin window (SW) and leukocyte migration tests (LMT's). Simultaneous measurements were made of the in vitro (LMT) reactivity to Rlll-murine mammary tumor virus, virions and/or puri fied glycoprotein with a molecular weight of 55,000. Among clinically disease-free patients tested 6 to 12 months postoperatively, positive SW responses were found in 86% of Stage 0 cases, in 57% of those invasive breast cancer patients who subsequently survived without recurrence for 5 or more years, and in 26% of those invasive breast cancer patients who developed recur rence less than 4 years postoperatively. Simultaneous CMI to Rlll-murine mammary tumor virus and autologous breast cancer was significantly more frequent among lymphoreticuloendothelial (LRE)-positive than among LRE-negative breast cancer patients tested 2 to 5, 6 to 12, and 13 to 39 months postoperatively. Among clinically disease-free LRE-positive patients tested 13 to 60 months postmastectomy, there was a striking correlation between migration indices to Rlll-glycoprotein with a molecular weight of 55,000 and autologous breast cancer. Our data indicate that: (a) the SW and LMT procedures could provide objective criteria for monitoring the effects of putative immunotherapeutic procedures on prognostically significant CMI; (b) the SW and LMT data support our earlier suggestion that the presence of LRE responses in breast cancer tissue reflects prognostically significant CMI to the cancer; (c) the SW, LMT, and LRE characteris tics individually and collectively demonstrate that preinvasive (Stage 0 in situ) breast cancers are commonly, if not universally, immunogenic; and (d) induced CMI to shared CMI determinants of Stage 0 in situ cancers might exert a retarding influence on subsequently developing breast cancer.