Characteristics and outcome of metastatic infant neuroblastoma

Abstract

BACKGROUND: Metastatic neuroblastoma in infancy behaved differently from those of older children. A significant proportion of them can regress spontaneously (stage 4S). The MYCN status, Shimada classification, DNA index & 11q rearrangement may affect the outcome and has been adopted as guidance for treatment stratification. We reviewed our experience on this cohort of patients. PATIENTS AND METHOD: This is a prospective cohort study. The patients were recruited from 5 regional hospitals which take care of all children with cancer locally. The data were collected by 2 data managers sponsored by Children Cancer Foundations. Infant was defined as patients ≤365-day-old. The staging was according to the INSS system. The presence of abnormal bone scan, MIBG scan in the skeletal area and distant lymphoid region will be classified as INSS stage 4. Treatments included POG low intensity chemotherapy protocol or high intensity regimens (modified from MSKCC or OPEC). MYCN was evaluated by FISH in the University Laboratory. RESULTS: From Jan 1993 to Dec 2006, a total of 13 patients were diagnosed and treated in the 5 centers (total 134 for all stages, 9.7%). There were 5 stage 4S patients, 4/5 received chemotherapy due to either rapidly enlarging tumors in their visceral organs or cord compression. There were 8 stage 4 patients, all received chemotherapy and 6 under intensive protocols. The median age was 0.28 yrs (range 0.08-0.57 yrs) for stage 4S and 0.7 yrs (range 0 - 0.84 yrs) for stage 4. None of the stage 4S and 30% of stage 4 tested had MYCN amplification. 4/5 stage 4S patients survived at a median follow-up of 8.6 yrs (0.1-11.8 yrs). The only mortality was due to hepatic rupture without prior chemotherapy. For stage 4 patients, 6/8 patients survived at a median follow up of 3.3 yrs (0.1-8.8 yrs). Both fatal cases died of disease progression and they don't have MYCN amplification. CONCLUSION: In our infant metastatic neuroblastoma cohort, stage 4 neuroblastoma was even more common than stage 4S. All of our survived stage 4S patients required treatment and their long term outcome was excellent. Our stage 4 patients also had better outcome than older children with stage 4 disease.