[Different treatment regimens for primary central nervous system lymphoma:based on SEER database]

Objectives: To explore the prognostic factors of primary central nervous system lymphoma(PCNSL) and to analyze the efficacy of different treatment methods. Methods: Clinical data of 4 812 patients with PCNSL in SEER database from January 1975 to December 2016 were retrospectively analyzed.Among them, 2 831 were male and 1 981 were female, the ratio of male to female was 1.4∶1.0.There were 2 236 cases(46.47%) under 60 years old, 1 718 cases(35.70%) aged 60 to 74 years old, and 858 cases(17.83%) aged 75 years old or above. Two thousand four hundred and seventeen cases(50.23%) had supratentorial tumors, 299 cases (6.21%) had infratentorial tumors, and 554 cases(11.51%) had multiple brain tumors, 1 542 cases (32.04%) were other or unspecified location.Three thousand five hundred and thirteen cases(73.00%) had diffuse large B-cell lymphoma (DLBCL), 234 cases(4.86%) had non DLBCL, 1 065 cases (22.13%) had other or unspecified types of tumor.The treatment included 2 011 cases (41.77%) of biopsy, 61 cases (1.27%) of subtotal resection(STR), 54 cases (1.12%) of gross total resection(GTR), 2 384 cases (49.54%) of biopsy and chemotherapy, 159 cases (3.30%) of STR and chemotherapy, 144 cases (3.00%) of GTR and chemotherapy.Univariate and multivariate Cox regression models were used to analyze the prognostic factors affecting the overall survival of the patients.Fine-Gray test and competitive risk model were used to analyze the prognostic factors affecting cancer-specific survival.Kaplan-Meier method and Log-rank test was used for survival analysis. Results: Univariate and multivariate Cox regression analyses showed that age, race, marital status, tumor site, pathological subtype, surgery, chemotherapy, combined with other malignant tumors, and HIV infection were the independent prognostic factors affecting the overall survival of PCNSL patients.The results of Fine-Gray test and competitive risk model analyses showed that age, race, marital status, tumor location, pathological subtype, surgical method, chemotherapy, combined with other malignant tumors, and HIV infection were independent prognostic factors affecting cancer-specific survival, while gender and radiotherapy had no significant correlation with cancer-specific survival.Compared with biopsy, PCNSL patients may benefit from surgical resection (STR:HR=0.805, 95%CI:0.656‒0.989, P=0.04; GTR:HR=0.521, 95%CI:0.414‒0.656, P<0.01).Kaplan-Meier survival analysis showed that the median survival time of biopsy+chemotherapy group was 28 months (95%CI:24.497‒31.503), 2 months (95%CI:1.756‒2.244) in the biopsy group, 2 months (95%CI:1.410-2.590) in the STR group, 19 months (95%CI:0‒39.311) in the biopsy+chemotherapy group, 67 months (95%CI:46.187-87.813) in the STR+chemotherapy group, 84 months (95%CI:57.448‒110.552) in the GTR+chemotherapy group.The median survival time of patients with different treatment methods was statistically significant (P<0.01). Conclusions: Surgical resection may improve the prognosis of some PCNSL patients.Patients who have access to receive GTR or STR combined with chemotherapy may have prolonged Cancer-specific survival.