The effects of PS-K on long-term survival of uterine cervical cancer patients treated with radiation was studied. The patients receiving PS-K were anxious about curability more or less at the time of completion of radiation therapy. Between 1977 and 1983, out of 96 patients with stage III, IV uterine cervical cancer treated with radiation, 27 were given PS-K as adjuvant therapy. The number of cases with PS-K administration were 15 (23%) out of 64 in stage IIIb, seven (37%) out of 19 in stage IVa and five (38%) out of 13 in stage IVb. Out of 27 patients administered PS-K, 19 were given the agent within three months after irradiation and the remaining eight after recognition of recurrence or metastasis. As a rule, PS-K was given orally, 3.0 g per day, intermittently in the pattern of two weeks per month. Judgement of the effects of PS-K was made in comparison with the survival rate of the patients with and without PS-K, and then by observation of the changes of the PPD skin test, ESR, appetite and body weight as early effectiveness of PS-K. The results were as follows. Obvious prolongation of survival was recognized in the patients with PS-K after irradiation. Namely, the cumulative five-year survival rates of stage IIIb were 65% and 49% with and without PS-K, respectively. Improvement by PS-K as early effectiveness was obtained in seven cases (37%) out of 19. The conditions necessary for long-term survival with PS-K were thought to be as follows: that the tumor almost disappears as a result of irradiation and that the condition of the host is superior to that of the tumor in the tumor-host relationship. The effectiveness of intermittent administration of PS-K was suggested.