THE POTENTIAL ROLE OF IMMUNOCONJUGATES IN TARGETING CYTOTOXIC AGENTS TO BRAIN-TUMORS

Advances in surgical, radiation and chemotherapeutic techniques for th e treatment of tumours of the CNS have not improved the prognosis of t his type of cancer. Furthermore, the CNS represents a unique challenge to traditional chemotherapy because of the blood-brain barrier, the v ariety of tumours present within the CNS and heterogeneity within a gi ven tumour type. Monoclonal antibody technology has provided a variety of new agents to explore as possible therapies for cancers. The use o f antibodies to target isotopes, toxins, drugs or enzymes to brain tum ours is currently being investigated. A number of phenomena may affect the ability of these immunoconjugates to reach the target and their e fficacy once at the target site. These include tumour susceptibility a nd accessibility, target antigen expression, the immune response of th e patient and tumour heterogeneity. We conclude, based on our research and that of others, that immunoconjugates are effective against compa rtmentalised tumours in the CNS, and their primary role may be in the treatment of residual disease or in combined therapeutic regimens.