72例标危型髓母细胞瘤放疗剂量对生存的影响

目的 回顾分析标危型髓母细胞瘤采用全脑全脊髓放疗剂量≤24 Gy和>24 Gy对预后的影响。方法 标危型髓母细胞瘤定义为年龄>3岁、未发生转移、肿瘤全切或近全切(残留≤1.5 cm³)。2003—2013年共入组72例初治儿童、青少年标危型髓母细胞瘤患者。患者术后接受全脑全脊髓+局部瘤床放疗和8个疗程辅助化疗,化疗方案为顺铂、司莫司汀或卡莫司汀联合长春新碱。按放疗剂量≤24 Gy和>24 Gy分为A、B组(20、52例),比较两组患者复发率和生存率。Kaplan-Meier法计算复发率和生存率并Logrank法检验组间差异。结果 A组接受全脑全脊髓放疗19.2~24.0 Gy,B组接受全脑全脊髓放疗24.1~30.6 Gy。放疗后66例(92%)患者完成全部辅助化疗。共11例患者复发。随访满3年患者48例,其中复发11例,死亡7例。全组3年EFS率为83%,3年OS率为86%。A组和B组患者3年EFS率分别为84%和83%(P=0.609), 3年OS率分别为85%和87%(P=0.963)。结论 标危型髓母细胞瘤经规范综合治疗效果较好,其中全脑全脊髓放疗剂量减少至19.2~24.0 Gy未影响疗效。

Impacts of radiation dose on survival in 72 patients with average-risk medulloblastoma

Objective To retrospectively analyze the impacts of a craniospinal radiation dose ≤24 Gy or>24 Gy on the prognosis of patients with average-risk medulloblastoma. Methods Average-risk medulloblastoma was defined as non-metastatic cancer in children more than 3 years old with complete or near-complete (residual tumor ≤1.5 cm³) resection of tumor. A total of 72 children and adolescents with newly diagnosed average-risk medulloblastoma were enrolled as subjects from 2003 to 2013. After radical resection of the tumor, all patients received craniospinal plus local tumor bed radiotherapy and 8 cycles of adjuvant chemotherapy using cisplatin-, semustine-, or plus vincristine-based regimens. Patients exposed to a radiation dose ≤24 Gy were enrolled into Group A (n=20), while patients exposed to a radiation dose>24 Gy were enrolled into Group B (n=52). The recurrence rate and survival rate were compared between the two groups. The recurrence rate and survival rate were calculated using the Kaplan-Meier method and the differences between the two groups were analyzed using the log-rank test. ResultsPatients in Group A and Group B received craniospinal radiotherapy with a dose of 19.2-24.0 Gy and 24.1-30.6 Gy, respectively. After radiotherapy, 66 patients (92%) completed all adjuvant chemotherapy. A total of 11 patients were recurrence. In all patients, the 3-year sample size was 48;the 3-year event-free survival (EFS) and overall survival (OS) rates were 83% and 86%, respectively. There were no significant differences in the 3-year EFS and OS rates between Group A and Group B (84% vs. 83%, P=0.609;85% vs. 87%, P=0.963). Conclusions The standard comprehensive therapy achieves satisfactory treatment outcomes for average-risk medulloblastoma, in which a craniospinal radiation dose decreased to 19.2-24.0 Gy has no impacts on treatment outcomes.