Department of Radiation Oncology, The Third Affiliated Hospital of Soochow University, The First Peoples' Hospital of Changzhou, Changzhou, 213003, China.
Department of Radiation Oncology, The Second Affiliated Hospital of Soochow University, Suzhou, 215004, China.
Sci Rep. 2017 Jun 13;7(1):3443. doi: 10.1038/s41598-017-03517-y.
Irradiation on hippocampus would lead to neuro-cognitive dysfunction in locally advanced nasopharyneal carcinoma (LA-NPC) patients accepting radiotherapy. Our study here aimed to investigate if undergoing hippocampus sparing (HS) volume modulated arc therapy (VMAT) would influence the plan quality in LA NPC patients. We designed three kinds of radiotherapeutic plans for 11 LA NPC patients: conventional VMAT (C-VMAT), HS-VMAT and HS intensity modulated radiation therapy with dynamic multileaf collimator (HS-dMLC). And the dose distribution on targets and surrounding organs at risk (OAR) were carefully evaluated. We found out that the expected doses on hippocampus were significantly lowered in HS-VMAT (899 ± 378 cGy) and HS-dMLC (896 ± 321 cGy) as compared to C-VMAT (1518 ± 337 cGy, p < 0.05), but meaningless difference was presented on plan quality of targets (p > 0.05). Moreover, lower radiation doses on brain stem were observed in HS-VMAT plan in comparison with C-VMAT plan (p < 0.05). However, there were no statistically meaningful diversities in the doses received by other OARs among all plans. Here we concluded that HS-VMAT presented promising advantages on protecting hipppcampus and brain stem as compared to C-VMAT and HS-dMLC, but enthusiastically had no effects on plan quality in LA-NPC patients.
对接受放疗的局部晚期鼻咽癌（LA-NPC）患者进行海马照射会导致神经认知功能障碍。我们的研究旨在探讨是否进行海马保护（HS）容积调强弧形治疗（VMAT）会影响 LA NPC 患者的计划质量。我们为 11 例 LA NPC 患者设计了三种放射治疗计划：常规 VMAT（C-VMAT）、HS-VMAT 和具有动态多叶准直器的 HS 调强放疗（HS-dMLC）。并仔细评估了靶区和周围危及器官（OAR）的剂量分布。我们发现，与 C-VMAT（1518±337cGy）相比，HS-VMAT（899±378cGy）和 HS-dMLC（896±321cGy）中海马的预期剂量明显降低（p<0.05），但靶区计划质量无明显差异（p>0.05）。此外，与 C-VMAT 计划相比，HS-VMAT 计划中脑干的照射剂量较低（p<0.05）。然而，在所有计划中，其他 OAR 接受的剂量没有统计学上的显著差异。因此，HS-VMAT 在保护海马和脑干方面较 C-VMAT 和 HS-dMLC 具有明显优势，但对 LA-NPC 患者的计划质量无明显影响。
