Cancer Detection and Therapy. Affinity of Neoplastic, Embryonic, and Traumatized Tissues for Porphyrins and Metalloporphyrins.

These experiments show that all porphyrins tested accumulate in neoplastic (induced and transplanted sarcomas, spontaneous and transplanted mammary carcinomas), embryonic and regenerating tissues. Introduction of a metal (zinc) into the porphyrin molecule did not destroy the tendency of the porphyrin to concentrate in tumors. The tendency of injected porphyrins and metalloporphyrins to accumulate in lymph nodes may limit the therapeutic usefulness of these compounds in all neoplastic diseases except lymphatic leukemias. The possibility of using small doses of radioactive metalloporphyrins for detecting deep cancer is being investigated.