Prospects for preneoplasia immuno-detection and cancer immuno-prevention

The three traditional modalities of cancer treatment: surgery, radio- and chemotherapy, even when applied in optimal fashion, leave over 50% of incurable patients, because of the metastatic disease. Hence the importance of preventive methods in cancer, by directing attention to the detection and treatment of preneoplasia. Focal preneoplastic lesions have been observed prior to the appearance of malignant epithelial tissues. The phenotypic patterns of preneoplasia seem to be as varied as those of neoplasia. In the frame of persistent multicellular hyperplasia, the appearance of enzyme-altered foci is supposed to be related to the origin of neoplasia, and in this sense these lesions can be considered pre-neoplasia. If there is any immune reaction to the non-self promoted by these lesions, their detection and their enhancement or induction by a vaccine would be a cancer immuno-prevention. Preliminary experiments and clinical pilot studies have shown a specific host-resistance to a pharmaceutical placental suspension (PS), when injected intradermally (DTHS-reactivity test) in patients with clinical conditions having, as histopathological substratum, a cellular adaptive (reactive) or neoplastic proliferation. Boosting this reaction by an adjuvant (BCG, corynebacterium parvum, etc.) would be an immunotherapeutic approach to cancer, as adjunct to standard treatments and in preneoplastic-bearing patients an immuno-preventive method in cancer. In vitro studies have shown that a glycoprotein of MW 40 kDa (P40), from an extract of placental suspension (PS) is recognized by patients' serum, (Ouchterlony's technique). The monospecific rabbit antiserum (MRA) raised to P40 glycoprotein also reacts with the serum of patients with positive DTHS reactions to PS.(ABSTRACT TRUNCATED AT 250 WORDS)