Rhabdomyosarcoma in infants younger than one year old: a report from the Italian Cooperative Group.

BACKGROUND

The management of rhabdomyosarcoma (RMS) in patients age < 1 year is particularly problematic and requires a tailored therapeutic approach. We report on the Italian Cooperative Group's 20-year study of 50 children with RMS who were age < 1 year at diagnosis.

METHODS

Patients were treated using multimodality therapeutic approaches that were based on three consecutive protocols. Chemotherapy was administered to all patients, with dosages calculated according to body weight; calculated doses subsequently were reduced by 33-50%. Radiotherapy was administered to 10 patients.

RESULTS

With a median follow-up of 76 months, 5-year event-free survival and overall survival rates were 42.3% and 61.7%, respectively. Local recurrence was the major reason for treatment failure. In particular, the local recurrence rate was high in patients who warranted radiotherapy but received none due to their age. Completeness of surgery and nodal involvement were the most significant prognostic factors. After a suitable reduction in dosage was made, acute toxicity was no different from what has been observed in older children. The most relevant toxic event was cardiotoxic death in a newborn (n = 1).

CONCLUSIONS

The current study confirmed that the outcome for infants with RMS is less satisfactory than for older children and that infants with RMS require more careful monitoring and specific treatment guidelines. The absence of local control is the major cause of treatment failure; aggressive conservative surgery should be encouraged, but more radiotherapy may be advisable in selected cases. Intensive chemotherapy is essential; a 33% dose reduction may ensure adequate tolerance. In addition, patients age < 3 months should not receive anthracyclines.