Pathology of soft tissue sarcomas: 238 cases of the childhood tumor registry

Until April 1981 malignant soft tissue sarcomas were registered from 238 patients. Rhabdomyosarcoma was the most common tumor (115/238 = 48.3%). The embryonal subtype was predominantly seen among the rhabdomyosarcomas (83/115 = 72.2%). Rhabdomyosarcomas were localized most frequently in the head and neck area (40/115 = 34.8%), followed by genitourinary system (15/115), pelvis soft tissue (12), abdomen (10) and extremities (10). Non-rhabdomyosarcomatous soft tissue sarcomas (123/238 = 51.7%) were synovial sarcomas (20 = 8.4%), fibrosarcomas including spindle cell sarcoma (17 = 7.4%), leiomyosarcomas (12 = 5.0%), malignant tumors of the vascular system (11 = 4.6%) and neurofibrosarcomas (9 = 3.8%). Other types of sarcoma were extremely rare. 42 (17.6%) of all soft tissue sarcomas could not be classified histogenetically. Rhabdomyosarcomas could be diagnosed much more accurately (105/115 = 91.3%), compared to all other soft tissue sarcomas (99/121 = 81.8%). At present, the most difficult diagnostic problems remain with the tumors of connective tissue, in particular with fibrosarcomas and with the differential diagnosis of juvenile fibrosarcomas versus juvenile fibromatoses.