21例原发性中枢神经系统淋巴瘤临床分析及文献复习

Clinical Analysis of Primary Central Nervous System Lymphoma: of 21 Cases Report

目的:原发性中枢神经系统淋巴瘤(Primary central nervous system lymphoma,PCNSL)指原发于中枢神经系统,无其它系统播散的淋巴瘤。近年来发病率呈上升趋势且预后较差。本研究目的在于探讨PCNSL的合理诊断方法及治疗方式。方法:回顾性分析自1993年6月至2006年6月经病理证实的21例原发性中枢神经系统淋巴瘤的临床特征、诊断方法及治疗方式。采用SPSS11.5软件包进行统计学分析。结果:男性12例,女性9例,中位年龄50岁(46～55岁)。单发病灶15例,多发者6例。CT、MRI检查示明显的肿物占位效应,边界清楚,伴周围水肿。病理检查均为B细胞淋巴瘤,脑脊液未见癌细胞。3例行立体定向穿刺活检,18例行手术治疗完全或部分切除肿瘤。17例术后或立体定向穿刺术后行放、化疗综合治疗。10例术后先行放疗后行化疗,7例先行化疗后行放疗。Kaplan-Meier分析全组中位生存期(Mediansurvivaltime,MST)22.6个月,2年生存率44.5%。经Log-Rank检验,先放后化组与先化后放组的生存期未见统计学差异(P=0.0547)。前者中位生存期36个月,2年生存率66.7%;后者中位生存期19个月,2年生存率35.7%。结论∶原发性中枢神经系统淋巴瘤采用化疗和放疗综合治疗有望提高生存率。手术的意义仅仅在于取活检,并不能延长生存期。对于影像学高度怀疑的病例应行立体定向穿刺活检明确诊断,不必手术。放化疗的顺序对于患者总生存期并无影响。但先放后化组与先化后放组的2年生存率、中位生存期仍然存在较大差异。先放后化组好于先化后放组。

Objective： Primary central nervous system lymphoma （PCNSL） is a type of lymphoma which originates in the central nervous system and does not spread to other systems. The incidence of PCNSL is increasing, and its prognosis is poor. This study aims to investigate the diagnosis of PCNSL and to explore the most effective treatment for PCNSL in immunocompetent patients. Methods： Twenty-one cases （12 men and 9 women） with pathologically confirmed PCNSL were treated in our hospital from June 1993 to June 2006. The clinical characteristics, the differential diagnosis and the treatments were reviewed retrospectively. SPSS 11.5 statistical analysis software was used to compare the two methods of treatment： chemotherapy after radiotherapy and radiotherapy after chemotherapy. The survival curves were calculated according to the Kaplan-Meier method and compared the Log-rank test. Results： The age of the patients ranged from 46 to 55 years old （median age=50）. Multiple lesions were reported in 6 cases and single lesions in 15 cases. Computed tomography （CT） and magnetic resonance image （MRI） showed unique or muhiple periventricular, uniformly enhancing lesions with mass effect, clear margins and moderate perifocal edema. All cases were B-cell lymphoma. No positive case of cere- brospinal fluid （CSF） was ibund upon cellular examination. Three cases received siereotactic brain biopsy while others were given surgical treatment. Two cases received radiotherapy only after surgery,two cases received chemotherapy only after stereotactic brain biopsy while the remaining 17 cases received both radiotherapy and chemotherapy after stereotactic brain biopsy or resection. We divided the 17 patients into two groups： Group 1 and 2. Group 1 was given chemotherapy after radiotherapy, while Group 2 was given radiotherapy after chemotherapy. Kaplan-Meier analysis showed that the median survival time （MST） was 22.6 months and the 2-year survival rate was 44.5% across the whole group. Log-Rank test revealed that the survival time shows no statistical difference between Group 1 and Group 2 （P=-0.054 7）. The MST of Group 1 and Group 2 were 36 months and 19 months and the 2-year survival rates were 66.7% and 35.7%, respectively. Conclusion： PCNSL often occurs in middle-aged patients, with intracranial hypertension as the main clinical manifestation. B-cell lymphoma is the main pathological subtype. It is difficult to distinguish PCNSL from other central nervous system tumors only according to their clinical manifestations and radiological findings. Accurate diagnosis is determined by pathological examination. Resection provides no therapeutic benefit but should be reserved for the rare patients with neurologic deterioration due to herniation. PCNSL suspected in neurologic imaging must be confirmed via stereotactic biopsy. Characteristic imaging features should corroborate the diagnosis and surgery should be avoided. The combination of radiotherapy and chemotherapy was feasible and efficient. It improves tumor response rates and survival rates compared with whole brain radiotherapy （WBRT） alone or chemotherapy alone. High-dose MTX-based chemotherapy plus WBRT （30~40Gy） showed significant efficacy for PCNSL. The sequence of radiotherapy and chemotherapy did not significantly influence the overall survival, but the MST and the 2-year survival rate are significantly different between the two groups. Radiotherapy followed by chemotherapy is superior to chemotherapy followed by radiotherapy.