The clinical features and prognosis of rhabdomyosarcoma: follow-up studies on pediatric tumors from the Japanese Pediatric Tumor Registry 1971-1980. Part II. Committee of Malignant Tumors, Japanese Society of Pediatric Surgeons.

A retrospective study was conducted on 126 patients with rhabdomyosarcoma enrolled in the Japanese Pediatric Tumor Registry between 1971 and 1980. The age of the patients ranged from less than 1 year to 15 years, and the male to female ratio was 1.3:1.0. Primary sites included the pelvis (37.3 per cent), abdomen (23.8 per cent), head and neck (21.4 per cent), thorax (9.5 per cent), extremities (6.4 per cent) and unknown (1.6 per cent). According to the staging system of the Japanese Society of Pediatric Surgeons, the extent of disease was classified into stages Ia (26.2 per cent of the total); Ib (14.6 per cent); II (12.6 per cent), III (29.1 per cent) and IV (17.5 per cent). The clinical stage was significantly correlated with survival outcome in this series (p less than 0.05). Age, sex, histology and primary site per se had no independent prognostic influence on tumor-free survival. With regard to treatment modalities, surgery was performed in 94.0 per cent of the patients, and radiotherapy at a mean dose of 37 Gy, and/or multi-agent chemotherapy in 41.7 per cent and 80.0 per cent, respectively. The patients who underwent total excision had a better survival outcome than those who did not (p less than 0.05). Combination chemotherapy such as VAC was more commonly administered in the latter study period. The overall 2-year tumor-free survival rate (2YTFSR) significantly improved from 24.0 per cent in the former period between 1971 and 1975 to 48.7 per cent in the latter period between 1976 and 1980 (p less than 0.05).