Paratesticular rhabdomyosarcoma: Importance of initial therapy.

PURPOSE

To evaluate factors associated with progression-free and disease-specific survival in patients with paratesticular rhabdomyosarcoma, we performed a cohort study. Also, since many patients present to our institution after initial therapy, we analyzed the effects of salvage therapy for scrotal violation.

PATIENTS AND METHODS

We retrospectively reviewed the records of all consecutive patients with histologically confirmed paratesticular rhabdomyosarcoma treated at our institution between 1978 and 2015. Fifty-one patients were initially identified, but two with incomplete data were excluded from analysis. Variables evaluated for correlation with survival were TNM staging, Children's Oncology Group Soft Tissue Sarcoma pretreatment staging, margins at initial resection, presence of scrotal violation, hemiscrotectomy and/or scrotal radiation. The log-rank test was used to compare survival distributions.

RESULTS

For the analytic cohort of 49 patients, the median age and follow-up were 15.7years (95% CI: 14.2-17.5, range: 0.8-25.1years) and 6.9years (95% CI: 4.4-9.0, range 0.2-37.5years), respectively. The 5-year overall disease-specific survival was 78.7% (95% CI: 67.7%-91.4%) and the progression-free survival was 66.9% (95% CI: 54.8%-81.6%). Median time to recurrence was 0.9years (95% CI: 0.7-0.9, range 0.1-6.2years). Scrotal violation occurred in 41% (n=20) and tripled the risk of recurrence for patients not appropriately treated with either hemiscrotectomy or scrotal radiation therapy (RR=3.0, 95% CI: 1.16-7.73).

CONCLUSIONS

The strongest predictors of disease-specific survival were nodal status and distant metastasis at diagnosis. Scrotal violation remains a problem in paratesticular rhabdomyosarcoma and is a predictor of disease progression unless adequately treated. The risk of progression could be reduced with appropriate initial resection.

LEVEL OF EVIDENCE

Level IV; retrospective study with no comparison group.