Abstract:

Objective To retrospectively analyze the clinical characteristics of sonic hedgehog (SHH) medulloblastoma (MB) in children, and to explore the prognostic factors. Methods The clinical data of SHH MB children from June 2015 to October 2019 were retrospectively analyzed. The overall survival rate and event-free survival rate were calculated by the Kaplan-Meier method. The survival rate between groups was compared by log-rank test. Cox proportional hazards regression model was used for multivariate analysis. Results A total of 99 children (62 boys and 37 girls) with SHH MB were enrolled. The median age was 6.0 (3.3-6.0) years, of which 75 children were ≥3 years old and 24 children were <3 years old. There were 66 cases of M₀ stage and 33 cases of M₊ stage. Total resection was performed in 72 children and near total resection in 27 children. The main pathological type was desmoplastic/nodular MB (DMB). Tumor origin sites were commoner in midline sites (fourth ventricle, posterior fossa, cerebellar vermis). SUFU germline variation was found in two children. The median follow-up time was 3.2 (2.2-4.1) years, the 3-year EFS rate was (61.0±5.0) %, the 3-year OS rate was (72.2±4.6) %, and 39 children (39.4%) had progression or recurrence. The 3-year OS rates of DMB and MB with extensive nodularity (MBEN) <3 years old are (80.0±10.3) % and (57.1±18.7) %, respectively. Among them, 12 patients with M₀ stage, without MYCN amplification and SUFU germline variation only received chemotherapy without radiotherapy. Cox regression model analysis showed that M₊ stage, TP53 mutation or MYCN, GLI2 amplification, and pathological type of large-cell/anaplastic was an independent risk factor for the prognosis of the disease (P<0.05). Conclusions The prognosis of SHH MB children is related to M stage, pathological type, TP53 mutation, MYCN or GLI2 amplification. Infants with pathological types of DMB and MBEN without the above risk factors and SUFU germline variation have a better prognosis, so radiotherapy is not necessary.

Key words: medulloblastoma, prognosis child