Impact of extensive surgery in a multidisciplinary approach of parameningeal rhabdomyosarcoma in children, adolescent and young adult population.

[CONTEXT AND OBJECTIVES] Parameningeal (PM) site is a well-known unfavorable site for rhabdomyosarcoma (RMS). PM RMS are usually considered unresectable and treated by radiochemotherapy. This study reviews our experience with a multidisciplinary approach, including extensive surgery.

[METHOD] We included all patients treated for PM RMS requiring extensive surgery from January 1992 to December 2021.

[RESULTS] Thirty-one patients were included with a median age of 6 years (range 6 months-17 years). The primary site was the infratemporal fossa in 81 %, nasopharynx in 13 %, and middle ear/paranasal sinus in one case each. At diagnosis, 23 % had lymph node involvement, and 13 % had distant metastases. Twenty-six patients received neoadjuvant chemotherapy before extensive surgery, while five underwent extensive surgery after radiochemotherapy. Free flap reconstruction was needed for 71 % of patients. Adjuvant radiotherapy (median dose: 50 Gy) was performed in 24 patients, with a median delay of 7.5 weeks post-surgery (range 3-13 weeks). Seven recurrences (23 %) were observed: four local relapses, two leptomeningeal spreads, and one distant metastasis. The median follow-up was 81 months (range 16-223 months). The median time to relapse was 12 months (range 6-36 months). Five-year event-free and overall survival rates were both 73.9 %, with a local failure-free survival of 85.7 %.

[CONCLUSION] Our study suggests that incorporating extensive surgery in PM RMS treatment improves long-term local control and survival, even in advanced cases with unfavorable features.