Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Pediatric Abdominal Rhabdomyosarcoma: Experience of a Reference Pediatric Oncosurgical Center.

BACKGROUND: Pediatric abdominal rhabdomyosarcoma (RMS) represents an oncosurgical challenge. For adults with peritoneal carcinomatosis and for children/adolescents with desmoplastic small round cell tumors (DSRCT), cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) has been shown to be an effective treatment. Thereby, we present the largest series on CRS and HIPEC in patients with abdominal RMS.

PATIENTS AND METHODS: Between August 2013 and January 2024, 18 patients (9 female and 9 male) with abdominal RMS underwent CRS and HIPEC at our institution. All patients were treated according to an institutionalized protocol. The indication for surgery was established by a multidisciplinary national tumor board. HIPEC was performed using cisplatin (37.5-100 mg/m2) and doxorubicin (15-30 mg/m2) for 60 min at 42°C. A retrospective review of patient's records was performed.

RESULTS: The median age at operation was 3.8 years. A complete cytoreduction was achieved in 17/18 patients. Median length of hospital stay was 11 days. Mean length of ICU stay was 2.5 days. No procedure-associated complications and no major short-/long-term toxicities were recorded. The median follow-up was 20 months. The 5-year overall survival (OS) and event-free survival (EFS) were 72% and 53%, respectively. Patients >10 years and those with alveolar histology had the worst prognosis (OS 0%). Patients with relapse after HIPEC (6/18) had a significantly poorer survival compared with those without recurrence (OS 33% vs. 100%, p = 0.001).

CONCLUSIONS: CRS and HIPEC are effective in patients with abdominal RMS. Patients >10 years, those with alveolar RMS and those with relapse after HIPEC had the worst outcome.