The purpose of this study was to evaluate the clinical characteristics and outcomes of patie nts with neuroblastoma aged less than 1 year.

From January 1997 to December 2007, 41 patients aged less than 1 year were diagnosed with neuroblastoma. Patients were divided into 3 risk groups according to the stage of the disease and N-myc amplification. Low-risk patients underwent surgery with (stage 2) or without (stage 1) short-term chemotherapy. Intermediate-risk patients underwent chemotherapy and surgery with or without local radiation therapy. High-risk patients underwent chemotherapy, surgery, radiation therapy, and high-dose chemotherapy/autologous stem cell rescue (HDCT/ASCR).

While tumor relapse occurred in only 1 patient, 7 patients died of treatment-related toxicities. Causes of treatment-related death included infection during conventional chemotherapy in 5 patients and acute myocarditis during HDCT/ASCR in 2 patients. The overall 5-year survival (±standard error) and 5-year event-free survival (EFS) rates after diagnosis for all 41 patients were 82.8±5.9% and 80.0±6.3%, respectively, with a median follow-up of 58 (9-137) months. The 5-year EFS rates for low-risk, interme diate-risk, and high-risk patients were 100%, 68.4±10.8%, and 66.7±19.3%, respectively.

Increased efforts to reduce infection-associated toxicity deaths during conventional chemotherapy are needed to further improve the survival of patients with neuroblastoma aged less than 1 year.