Editorial: Advances in the treatment of primary central nervous system lymphoma

This is the authors' abstract. We don't add key points for this paper.

Percival Bailey in 1929, but he did not explicitly name it "lymphoma", but considered this type of tumor to be a perivascular sarcoma, originating from the perivascular sheath of the leptomeninges (1). In 1938, Yuile C. L. described it as "primary reticulum cell sarcoma of the brain" by a case report (2). Until 1963, Bursrein, S. D. et al found that reticuloendothelial neoplasms of the central nervous system were histologically similar to lymphoma (3). Nevertheless, they included this type in the category of reticulum cell sarcoma. In 1974, James M. Henry et al. found that primary "reticular cell sarcomato-microgliomatosis" of central nervous system was histologically identical to malignant lymphoma, so it was named primary central nervous system lymphoma(PCNSL)(4).After nearly a century of development, great progress has been made in the diagnosis, classification, staging, treatment and prognosis of PCNSL.The ultimate goal of these basic and clinical researches is to prolong the life of patients and improve their quality of life. This research topic focuses on the advances in the treatment of PCNSL, wish to improve the prognosis of this rare central nervous system tumor. This research topic contains 5 articles, involving chimeric antigen receptor T(CAR-T) cell therapy, autologous hematopoietic stem cell transplantation, new chemotherapy regimens and new prognostic models.In the article by Kotaro Miyao et al. from Japanese Anjo Kosei Hospital, they reviewed the role of Chimeric antigen receptor T (CAR-T) cells in PCNSL (5). CAR-T cell therapy has been proved to be effective in peripheral B-cell lymphoma, myeloma and other hematologic malignancies, but its role in PCNSL is still under clinical study. This review highlighted current state of CAR-T cell therapy in PCNSL, its resistance mechanisms and future directions in the field. It was suggested that the response rate and durable response of PCNSL could be improved by CAR-T cells combined with conventional high-dose MTX chemotherapy.Combining CAR-T cells with conventional high-dose MTX chemotherapy could also improve the response rate and durable response for PCNSL, and reduce the dose of conventional high-dose chemotherapy and its toxicity.Hospital attempted to identify the status of autologous stem-cell transplantation (ASCT) by meta-analysis (6). The status of ASCT in the PCNSL is still controversial. By analyzing data from PubMed, Embase, and Cochrane Library databases on newly diagnosed PCNSL, they found that consolidation with ASCT after chemotherapy may achieve better therapeutic outcomes：complete remission rate, overall response rate, and relapse rate were 80%, 95% and 19%, 5-year PFS and OS rates were 65% and 69%, comparable to whole brain radiation. Most of the current studies on the application of ASCT in PCNSL are single-arm studies or retrospective studies. Based on this meta-analysis, we expect further randomized double-blind controlled studies with a large sample size and higher evidence level.Xuefei Sun et al. from Chinese Beijing Tiantan Hospital analyzed 243 patients with PCNSL retrospectively (7). They found that among 95 patients receiving non-myeloablative sequential consolidation chemotherapy by either pemetrexed or etoposide plus cytarabine, median PFS was 28 months, and estimated 4 years overall survival was 78.7%, higher than 14 months and 61.6% for all patients. Age and early treatment response were independent predictors of survival. It was suggested that In conclusion, this research topic brings together the latest cuttingedge researches on the treatment and prognosis of PCNSL, which makes a contribution to the development of the treatment of PCNSL and points out the direction of further research. Finally, we would like to thank the authors for publishing their excellent papers on our research topic, as well as the reviewers for their professional opinions and the editorial staff for their support.