[A case of remarkable regression of lung adenocarcinoma with PSK immunotherapy]

An asymptomatic 84-year-old man was admitted to our hospital for a further examination of an abnormal shadow in the right lower lung (S9) on chest X-ray film. Sputum and specimens of transbronchial brushing showed cytological characteristics of well differentiated adenocarcinoma. Considering his age, his family did not agree to any surgical operation, irradiation or intensive chemotherapy. Therefore, using PSK: 3.0 g/day, immunotherapy was started on October 26, 1984. However, the abnormal density continued to increase in size and was observed radiographically to infiltrate to the neighboring segment (S6) over the following four months. From March 1985, the tumor regressed gradually and had almost disappeared on chest X-ray films by December 1985. Since then, this remission has been maintained by administration of PSK alone (3.0 g/day).