Menon D, Chelakkot P G
Department of Radiation Oncology, Amrita Institute of Medical Sciences, Amrita University, Kochi, Kerala, India.
Indian J Cancer. 2017 Apr-Jun;54(2):409-414. doi: 10.4103/ijc.IJC_216_17.
Radiation therapy is a major treatment option in the management of primary central nervous system (CNS) tumors, though recurrences after primary treatment, especially in high-grade glial tumors, is a challenge for treating physician. Advances in the field of radiation have made reirradiation a feasible option in recurrent CNS tumors.
Details of patients with primary CNS lesions who presented between 2009 and 2016, with recurrent CNS lesions, and who were treated with reirradiation were retrieved from electronic medical records, as a departmental audit, and the outcome was analyzed.
A total of 33 patients received reirradiation. Median follow-up was 112.7 months. Median age at presentation was 36 years. On completing initial treatment, 42.4% had no residual disease. Median time to symptomatic recurrence was 51.33 months. For reirradiation, stereotactic radiotherapy was used in 27.3%, stereotactic radiosurgery in 12.1%, and intensity-modulated radiation therapy in 36.4%. Mean cumulative 2 Gy equivalent dose (EQD2) was 111.00 ± 15.287 Gy. At the last follow-up, 57.6% of patients were alive, and 27.3% had succumbed to the disease. Median OS was 187.67 months. Three-year survival after reirradiation was 74.1%.
Our study is probably one of the first from the Indian subcontinent analyzing a series of reirradiation in primary CNS tumors. Our survival subsequent to reirradiation is comparable to that in available literature; which are also mostly retrospective. Our analysis also substantiates that younger patients, longer intervals between the two sets of radiation and biologically effective dose <100 Gy and EQD2of <100 Gy are factors that favorably improve the survival after reirradiation as has been shown in literature.
放射治疗是原发性中枢神经系统（CNS）肿瘤治疗的主要选择，尽管初次治疗后复发，尤其是高级别胶质瘤，对治疗医生来说是一项挑战。放射领域的进展使再程放疗成为复发性中枢神经系统肿瘤的可行选择。
作为科室审核，从电子病历中检索2009年至2016年间出现原发性中枢神经系统病变、复发性中枢神经系统病变并接受再程放疗的患者详细信息，并分析结果。
共有33例患者接受了再程放疗。中位随访时间为112.7个月。初次就诊时的中位年龄为36岁。完成初始治疗后，42.4%无残留疾病。出现症状性复发的中位时间为51.33个月。对于再程放疗，27.3%使用立体定向放射治疗，12.1%使用立体定向放射外科，36.4%使用调强放射治疗。平均累积2 Gy等效剂量（EQD2）为111.00±15.287 Gy。在最后一次随访时，57.6%的患者存活，27.3%死于该疾病。中位总生存期为187.67个月。再程放疗后的三年生存率为74.1%。
我们的研究可能是印度次大陆首批分析原发性中枢神经系统肿瘤系列再程放疗的研究之一。我们再程放疗后的生存率与现有文献相当；现有文献大多也是回顾性的。我们的分析还证实，年轻患者、两组放疗之间的间隔时间较长以及生物有效剂量<100 Gy和EQD2<100 Gy是有利于改善再程放疗后生存率的因素，正如文献中所显示的那样。
