Hepatoblastoma in children aged less than six months at diagnosis: A report from the SIOPEL group

The purpose of this study was to evaluate clinical characteristics, treatment, and survival of children, who were diagnosed with hepatoblastoma (HB) in their first 6 months of age, enrolled in the SIOPEL 2 and 3 protocols. Seventy-nine patients, treated between 1994 and 2006, were analyzed after stratification into three age groups: <1 month, between 1 and 3 months, and between 3 and 6 months. All received preoperative chemotherapy. Clinical characteristics were similar in both trials: 4 patients had pulmonary metastases at diagnosis, 4 had α-fetoprotein <100 ng/ml, 68 were operated by partial hepatectomy, and 7 received liver transplant. Chemotherapy courses were delayed in 8.5%, 8.4%, and 11.8% of cycles in the three groups. Doses were calculated according to weight for children <5 and 5-10 kg, and further reduced in 18.1%, 6.8%, and 5.9% of cycles. Acute toxicity was manageable. Long-term hearing loss was the major problem at follow-up occurring in two-thirds of children. Ten patients experienced progression or relapse, and 5 of 10 died. After a median follow-up of 5.6 years, the 5-year overall survival (OS) and event-free survival (EFS) were 91% (95% confidence interval [CI]: 84-96%) and 87% (95% CI: 78-92%), respectively. The 5-year OS and EFS of children <6 months of age affected by HB seem to be similar to those documented in the elder children. Dose reduction does not seem to jeopardize the long-term outcome and may explain the lower toxicity profile. Ototoxicity though appears as high as in the whole population of SIOPEL 2 and 3. The treatment for these children should be further explored in international studies, particularly focusing on prevention of hearing loss