Outcome of Female Pediatric Patients Diagnosed With Genital Tract Rhabdomyosarcoma Based on Analysis of Cases Registered in SEER Database Between 1973 and 2006

Abstract
Objectives: We analyzed outcomes of pediatric rhabdomyosarcoma (RMS) of the female genitourinary (GU) tract using the Surveillance Epidemiology and End Result database. Materials and Methods: Females (0 to 19 years of age) diagnosed with RMS of GU sites between 1973 and 2006 were included in the analysis as 2 groups, 0 to 9 and 10 to 19-year-olds. They were compared for primary site distribution, stage, histology, and therapy. Kaplan-Meier method was used for survival analysis by histology, stage, and primary sites. Results: Sixty-seven cases were identified. Twenty-six cases (38.8%) had localized disease, 11 (16.2%) had regional disease, 15 (28.4%) had distant spread, and 15 (28.4%) were unstaged. The majority (85%) had embryonal RMS. Twenty-eight tumors originated in the vagina, 26 in the cervix/uterus, and 13 in other sites including vulva, labia, ovaries. Age groups did not differ with respect to race, cancer stage, histologic type, percent of cases treated surgically, and the proportion receiving radiotherapy. Vaginal RMS was predominant in the younger age group (68.4%). In the older age group, 65.5% had RMS of the cervix or uterus. This age-related prevalence of tumor sites was statistically significant (P<0.001). Survival of patients with embryonal and early-stage tumor was superior. There was no significant difference in survival by age or primary tumor site. Conclusions: This population-based study confirmed the significance of tumor histology and stage for female GU RMS patients. Tumor sites are strongly associated with age at diagnosis.