Chemotherapy as monotherapy for treatment of non-metastatic bladder/prostate embryonal rhabdomyosarcoma in children: preliminary report.

Objective: This work aims at evaluation of chemotherapy as mono-therapy for treatment of non-metastatic bladder/prostate embryonal rhabdomyosarcoma in children.

Patients And Methods: Between 1996 and 2002, 10 children presented with RMS of the bladder/prostate at a mean age of 6.6 years (range 1.5-18). Four patients had stage 2 disease and 6 had stage 3. The histology was embryonal in 8 and botryoid in 2. All patients received VAC chemotherapy for a mean duration of 14 months (range 12-18). CT or MRI was performed at 8 weeks, every 3 months in the first year and every 6 months thereafter.

Results: The mean follow-up duration was 48 months (range 12-96). At 8 weeks, 7 children showed more than 50% reduction in tumour size and the remaining 3 showed complete disappearance on CT or MRI. At final follow-up 8 patients are living, disease-free, with functioning bladder. The remaining 2 patients died of metastatic disease at 12 and 14 months from start of treatment. Out of the 8 survivors, 5 had complete disappearance of the tumour at last follow-up while 3 had residual tumour on CT/MRI. Those children underwent transurethral endoscopic resection and the pathology showed no evidence of malignancy in all. The 4-year disease-free survival was 100% for stage 2 and 66% for stage 3.

Conclusions: Chemotherapy as mono-therapy is effective treatment in children with stage 2 embryonal RMS of the bladder/prostate with the advantage of bladder preservation. Within stage 3, non-survivors had statistically significant larger tumours. Adjuvant therapy or more intensive chemotherapy might be required for those with large stage 3 tumours.