A rational approach toward determining the candidacy of the prostatic cancer patient for cryoimmunotherapy: an interim report.

While receiving only cursory attention compared to that of other malignant neoplasms, studies of patients with prostatic cancer have suggested that host responses, mediated in part by immunobiologic factors, may play a significant role in the pathogenesis and thus, the therapeutic management of this disease. For nearly a decade cryosurgery has gradually attained some degree of acceptance as one of the efficacious treatment modalities available in the therapeutic armamentarium for prostatic cancer. In addition to the localized destruction of the primary tumour, reports of secondary tumour cell destruction, i.e. of distant metastases, have supported the suggestion that cryosurgery, as documented in various animal species, may also be immunopotentiating in man. Although our understanding of immunopotentiation of the host's response to tumour via cryosurgery is far from complete, information derived from experimental studies demonstrating that the developement of an immunologic response following cryosurgery of the prostate may be attributed to androgenically and ontogenically dependent autoantigens may have clinical relevance. This together with knowledge that in the therapeutic management of the patient with prostatic cancer we are confronted with the treatment of an individual who, in the majority of cases, possesses waning immunocompetence, emphasizes the potential significance of evaluating what may be referred to as the 'cryosensitivity' of the prospective cryosurgical patient. At present this 'cryosensitivity' may be said to be dependent upon: (1) concentration of prostatic tissue [secretory(tumour?)]-specific or tumour-associated auto-(neo?) antigen(s); (2) physiologic state (elaboration of androgen), and (3) immunocompetence. It is hopeful that evaluation of these parameters may provide a rational approach toward determining the acceptability of cryosurgery as the treatment of choice in a given patient.