Cryoimmunology caught on in 1971 with a publication (Ablin, Soanes, Gonder) of 3 cases of metastatic prostate cancer with a regression of metastases after cryotherapy of primary tumor. From this time, we attached a big importance to cryoimmunology and many works were published (1976, 1983, etc.).
The immunologic answer to cryotherapy in prostate carcinoma is probably linked to the release of seized antigens, like PSA, and is both systemic and local, with a specific antitumorous. Many studies have demonstrated a change in immunologic answer after cryotherapy of tumors, both in laboratory animals (Ablin) and in men (Sesia, Fontana, et at.), using of complement, increase of immune globulines, especially IgE, appearance of tumor antibody, activation of Natural Killer and cytotoxic T Cells. Flock and Coll. have published their work about transperineal cryotherapy in prostate cancer, their results at 10 years were comparable to radical prostatectomy.
Our works have demonstrated an improvement of survival in patients treated with hormone therapy plus cryotherapy versus patients treated with hormone therapy alone. The most important points of the answer to cryotherapy are immunosensitivity, linked to antigenic mosaic of tumor target, and immunostaging (Ablin, Fontana), which classify host's immunocompetence in four stages, by evaluation of immune globulins, cell's answer and general conditions of patients. It is obvious that every factor that can reduce immunity, like thinning, cachexia, radiotherapy, chemotherapy, cortisone, anesthesia, surgery, stress, intercurrent diseases, can at the same time hamper immunological answer and also the results of cryotherapy.
Critical to the answer to cryotherapy is its quality: extension of cryonecrosis, temperature, time and number of applications, velocity of treatment. In some cases, Authors described an aggravation of prostate cancer after cryotherapy - recently, attention is attracted to antigenic intolerance and immunologic paralysis. Fontana (1995) has obtained good results using adjuvant therapy with Interleukin-2 in advanced prostate cancer.
In conclusion, we know that there is certainly an immunological answer to cryotherapy, but we need other trials to fix how we can exploit this answer and about some possible adjuvant therapy.