A PROSPECTIVE-STUDY OF NONRHABDOMYOSARCOMA SOFT-TISSUE SARCOMAS IN THE PEDIATRIC AGE GROUP

Nonrhabdomyosarcoma soft tissue sarcomas in infants and children are rare malignancies with most of the clinical data gained by retrospective analysis. In 1986, a prospective multicentered study was initiated by the Pediatric Oncology Group (POG) with a total of 75 cases now entered for epidemiologic examination. Median age of presentation was 12 years (range, newborn to 20 years). The male to female ratio was 2.3 to 1. The most common soft tissue tumor was synovial cell sarcoma ( 32 75, 42%), followed by fibrosarcoma ( 10 75, 13%), malignant fibrous histiocytoma ( 9 75, 12%), and malignant neurogenic tumors ( 8 75, 10%). Sixty-five percent of all tumors presented on the extremities (44% lower extremity, 21% upper extremity). Tumors of the trunk accounted for 28% (abdomen 15%, thorax 13%), whereas head and neck tumors were 7%. By TNMG classification, 16% presented as stage I, 21% as stage II, 33% as stage III, and 30% as stage IV. Age at presentation did not affect clinical site or stage. All upper extremity tumors presented with localized disease, whereas lower extremity tumors presented with regional nodal disease in 7% and metastatic disease (pulmonary) in 23% of the cases. Seventy-eight percent of the abdominal tumors were metastatic at diagnosis; the other 22% had extensive regional disease. In the thorax 78% had localized lesions with 22% having extensive regional disease. Ninety percent of synovial cell sarcomas were on the extremities: 84% localized disease and 12% metastatic spread at presentation. Sixty percent of the fibrosarcomas presented on the extremities with 80% having localized disease and 20% metastatic spread. Only 25% of the neurogenic tumors presented with localized disease, whereas 50% had metastases at the time of diagnosis. Because a significant percentage of nonrhabdomyosarcoma soft tissue tumors in the pediatric population present with regional and metastatic disease, incisional biopsy for diagnosis, surgical control of local disease, node sampling for accurate staging, and evaluation for metastatic spread remain crucial for maximizing outcome. © 1992.