Long-term disease-free survival following salvage brachytherapy for recurrent pediatric rhabdomyosarcoma: Two case reports and review of relevant literature

Purpose: Rhabdomyosarcoma (RMS) is the most common pediatric soft-tissue sarcoma, mostly involving the genitourinary (GU) tract, head and neck, and extremities. This study reports the long-term outcome of two infants with recurrent GU-RMS who underwent combination therapy with chemotherapy (ChT) and salvage brachytherapy (BT).

Methods and materials: An 18-month-old girl with vaginal bleeding and a 7-month-old boy with urinary retention presented with a diagnosis of vaginal, and bladder/prostate embryonal RMS, respectively. Surgical resection and ChT were done for both patients. However, both developed local recurrences after one year and subsequently, underwent second-line ChT and salvage interstitial high dose rate BT.

Results: The clinical target volumes for the first and second patients were treated to a totaldose of 32 Gy in 10 fractions and 35 Gy in 10 fractions, respectively, with two fractions delivered per day with a 6-h interval between fractions. After 9 years of follow-up, both patients are alive with natural growth and no late complication or evidence of recurrence.

Conclusions: Our report shows that BT (for patients with no prior history of irradiation) could result in long-term disease-free survival in well-selected pediatric patients with recurrent GU embryonal RMS without inflicting expected adverse effects of external beam radiotherapy.