Local hyperthermia in prostate cancer

We conducted a clinical trial evaluating the effects of hyperthermia in patients with carcinoma of the prostate, treating 20 patients with newly diagnosed carcinoma of the prostate with local microwave hyperthermia (915 MHz). Histological examination revealed hypoeremic effects and diffuse oedema with interstitial lymphoplasmatic cellular infiltration. However, necrotic tumour cells were not found in any of specimens. A second series consisted of 10 patients with metastasizing carcinoma of the prostate (n = 4 untreated; n = 6 hormone-resistant). For 8 weeks, epirubicin was administered once weekly, followed each time by local microwave hyperthermia 1 h later. The efficacy was evaluated according to the EORTC criteria. In 4 patients with untreated carcinoma no change was found in the size of the prostate or metastases. In 3 of the 6 patients with hormone-resistant carcinoma progressive disease was found, while the other 3 had stable disease. Only in 2 of the 10 patients did the grading of tumour regression reveal any improvement. Cytophotometric studies showed no change of DNA ploidy. Currently we consider hyperthermia unsuitable as monotherapy for carcinoma of the prostate, and the combination of epirubicin and hyperthermia is no more favourable than monotherapy with epirubicin alone. Further studies are necessary to evaluate other cytotoxic regimens and various patterns of application for hyperthermia.