Results in patients with cranial parameningeal sarcoma and metastases (stage 4) treated on Intergroup Rhabdomyosarcoma Study Group (IRSG) Protocols II-IV, 1978-1997: Report from the children's oncology group

Purpose. Determine outcome of patients with cranial parameningeal sarcoma and concurrent metastases treated on Intergroup Rhabdomyosarcoma Study Group (IRSG) Protocols II-IV. Patients. We identified 91 patients in the database, which includes newly diagnosed subjects <21 years old with rhabdomyosarcoma (RMS) and undifferentiated sarcoma, and reviewed their charts in detail. Results. The 54 males and 37 females were <1-19 years at diagnosis. Primary sites were nasopharynx-nasal cavity, middle ear/mastoid and parapharyngeal area ("better" sites, 55%), paranasal sinus and infratemporal-pterygopalatine area ("worse" sites, 42%), and other (3%). Sixty-eight percent of informative patients had direct intracranial extension. Major metastatic sites at diagnosis were lung (63%), bone marrow (33%), and bone (27%). Treatment included vincristine, actinomycin D, and cyclophosphamide (VAC) chemotherapy and radiotherapy to the primary tumor and up to five metastatic sites/tissues. Outcome. The estimated 10-year failure-free survival (FFS) rate was 32% (95% confidence interval [CI]: 22%, 42%). Sixty patients had progressive disease (N = 49) or death as a first event (N = 11); another developed myelodysplastic syndrome and died. Sites of first progression/relapse were distant (55%), local (12%), CNS extension (8%), mixed (6%), and uncertain (18%). Factors indicating likelihood of 10-year FFS included tumor arising in "better" versus "worse" sites (FFS 46% vs. 18%, P = 0.02) and embryonal versus other histology (FFS 37% vs. 19%, P=0.06). Conclusions. Cure was possible for some patients with metastatic cranial parameningeal sarcoma. Patients with the best outlook had embryonal RMS located in the nasopharynx/nasal cavity, middle ear/mastoid, or parapharyngeal region. Distant metastases were the most frequent type of recurrence, indicating that more effective systemic agents are needed to eliminate residual disease.