Hematological toxicity of craniospinal irradiation and the short-term clinical efficacy in medulloblastoma

Objective: To evaluate the hematological toxicity of craniospinal irradiation, and determine the short-term clinical efficacy and prognostic factors in medulloblastoma. Methods: Eight-seven patients who underwent craniospinal irradiation were retrospectively analyzed with respect to the changes in hematology during craniospinal irradiation. The effect of sex, age, tumor location, interval between surgery and radiation, interval time during radiation and radiation sequence on survival were also studied. Results: The 1, 2, 3-year overall survival (OS) and progress-free survival (PFS) rate were 95.0%, 92.4%, 84.9% and 93.7%, 89.8%, 80.8%, respectively. The incidence of 2-3 grade leucopenia was 90.8%, while the incidence of 1-2 grade thrombocytopenia was 70.1%, and the incidence of 3 grade thrombocytopenia was 1.1%. The incidence of 1-2 grade hemoglobin reduction was 16.1%. No patient had grade 3-4 hemoglobin reduction. Kaplan-Meier analysis shows that more favorable prognoses in terms of 3-year PFS were evident for 0-1 grade thrombocytopenia compared with 2-4 grade thrombocytopenia (χ² = 3.936, P < 0.05). And 3-year PFS and 3-year OS were evident for 0 grade hemoglobin reduction compared with 1-4 grade hemoglobin reduction (χ² = 10.269, 9.336, P < 0.05). The 3-year PFS between interval time during radiation < 3 days and ≥ 3 days was 84.6% and 68.6%(χ² = 4.413, P < 0.05). Conclusions: Hematological toxicity during craniospinal irradiation and the interval time during radiation were prognostic factors. (authors)