Othman Ramadhan, Abdullah Kurdistan Gh
Department of Internal Medicine, College of medicine, University of Duhok, Duhok, Iraq. Email:
Asian Pac J Cancer Prev. 2017 Jul 27;18(7):1729-1735. doi: 10.22034/APJCP.2017.18.7.1729.
Background: Brain tumours are the most common solid tumours in children. More than 50% of these tumours develop in the posterior cranial fossa. Long term survivors of posterior fossa tumours (PFT) suffer from neurocognitive and memory issues. We hypothesized that serial MRI scanning of brain would show differences in hippocampal and ACC volume change in PFT patients treated with and without chemo-radiotherapy. Material and Methods: Twelve patients (8 females and 4 males) underwent 76 serial MR imaging examinations before and during treatment for posterior fossa tumours. Seven patients (4 medulloblastoma, 2 as ependymoma and 1 high grade glioma) were treated with maximum surgical resection followed by adjuvant radiotherapy and chemotherapy (Group 1). The other five patients were diagnosed as pilocytic astrocytoma who were treated only with surgery (Group 2). Hippocampal volumes were obtained manually on high-resolution 3Tesla T1-weighted images and normalised to intracranial volume, while ACC thickness and volume were obtained automatically using FreeSurfer software. Results: After the treatment period, the change in normalised hippocampal volume from baseline was significantly lower in group 1 patients compared to group 2 (mean change -0.0001470 ± 8.981e-005; Mean ± SEM vs 0.0002765 ± 9.151e-005; Mean ± SEM, respectively, P=0.004). Displayed graphically, the negative hippocampal growth trajectory in group 1 gradually returned to a positive growth pattern. There were no statistically significant changes in ACC volume and thickness. Both groups had similar rates of pre-operative hydrocephalus. Conclusion: Compared to PFT patients treated with surgery alone, PFT patients treated with chemo-radiotherapy showed lower hippocampal volumes and altered hippocampal growth trajectory. Serial quantitative MRI measures of brain may provide a neuroanatomical substrate for assessing functional impact on normal brain function following treatment of posterior fossa tumours.
脑肿瘤是儿童最常见的实体肿瘤。其中超过50%的肿瘤发生在后颅窝。后颅窝肿瘤（PFT）的长期幸存者存在神经认知和记忆问题。我们假设，对接受和未接受放化疗的PFT患者进行脑部系列MRI扫描会显示海马体和前扣带回皮质（ACC）体积变化的差异。
12例患者（8例女性，4例男性）在接受后颅窝肿瘤治疗前及治疗期间接受了76次系列MR成像检查。7例患者（4例髓母细胞瘤、2例室管膜瘤和1例高级别胶质瘤）接受了最大程度的手术切除，随后进行辅助放疗和化疗（第1组）。另外5例患者被诊断为毛细胞型星形细胞瘤，仅接受了手术治疗（第2组）。在高分辨率3特斯拉T1加权图像上手动获取海马体体积，并将其标准化为颅内体积，而ACC厚度和体积则使用FreeSurfer软件自动获取。
治疗期结束后，第1组患者标准化海马体体积相对于基线的变化显著低于第2组（平均变化-0.0001470±8.981e-005；平均值±标准误，对比0.0002765±9.151e-005；平均值±标准误，P=0.004）。以图形方式显示，第1组海马体的负生长轨迹逐渐恢复为正生长模式。ACC体积和厚度没有统计学上的显著变化。两组术前脑积水发生率相似。
与仅接受手术治疗的PFT患者相比，接受放化疗的PFT患者海马体体积较小，且海马体生长轨迹改变。脑部系列定量MRI测量可为评估后颅窝肿瘤治疗后对正常脑功能的功能影响提供神经解剖学基础。
