The Department of Internal Medicine at Peking University Third Hospital was established as a comprehensive internal medicine department at the hospital's founding in 1958, with hematology serving as an independent specialty group. In 1984, the hospital formally established its subspecialties, and the Department of Hematology became an independent department, with Dr. Wang Liangxu becoming its first director after returning from overseas studies. In the same year, with approval from the Ministry of Health, a hematology research laboratory was formally established, equipped with independent laboratory personnel capable of performing hematological and bone marrow smear examinations independently. In 1997, Professor Ke Xiaoyan assumed the role of department director, leading the department to achieve nationally leading levels in the diagnosis and treatment of lymphoma and multiple myeloma, and establishing a multidisciplinary collaborative lymphoma diagnosis and treatment platform. In 2018, Professor Jing Hongmei became department director, further dedicating efforts to clinical cohort construction research across lymphoma subtypes, thereby enhancing the overall disciplinary development. The Department of Hematology at PUTH is currently one of the key specialties designated by both the Ministry of Education and Peking University Third Hospital, and was selected for the National Clinical Key Specialty Construction Project in 2023. The department currently operates 104 open beds, including 6 bone marrow transplantation beds and 20 beds at the airport campus. The department possesses robust technical capabilities, with a current staff of 88 physicians, nurses, and laboratory technicians, including 5 chief physicians/professors, 5 associate chief physicians, 9 attending physicians, 16 laboratory personnel, and 48 nursing staff. The Department of Hematology has a comprehensive diagnosis and treatment platform for lymphoma, multiple myeloma, and leukemia, managing over 5,300 patient cases annually. High-dose chemotherapy, hematopoietic stem cell transplantation, and cellular therapy are distinctive features of our department, which was among the first in China to pioneer peripheral blood stem cell transplantation and CAR-T cell therapy, earning considerable recognition. In September 2021, the PUTH-Yimiao Shenzhou CAR-T Cell Therapy Joint Research and Development Center was established, creating a CAR-T cell seed bank and conducting multiple basic and clinical research studies. The department has secured over 60 grants from the National Natural Science Foundation and provincial/ministerial-level funding, received a Second Prize for Science and Technology Progress from the Higher Education Outstanding Scientific Research Achievement Awards, published or co-authored over 30 books, published more than 400 papers, obtained 25 authorized patents, and completed 1 technology transfer. Multiple international symposiums and national continuing education training programs have been held, and nearly 100 master's and doctoral students have been trained. The Clinical Trial Drug Base of the Department of Hematology is a national-level hematology drug trial base. Since 1980, it has undertaken various clinical pharmacological research projects and was approved by the Ministry of Health in 1998 as one of the first batch of clinical pharmacology base specialties, becoming one of the first nationally certified professional institutions qualified to conduct clinical research on new drugs. Over the past five years, the department has undertaken 168 clinical drug trials, including 39 international multicenter projects, and served as the lead unit for 5 domestic multicenter clinical trials. These trials encompass clinical research on various new drugs, including hematological anti-tumor agents, treatments for anemia, thrombocytopenia, immunomodulators, antibiotics, hematopoietic growth factors, and cellular therapies. The covered population includes not only patients with hematological malignancies such as lymphoma, myeloma, and leukemia, but also those with benign hematological diseases and rare diseases. Over the past decade or more, the department has undergone 3 international audits, 3 CFDA inspections, and numerous inspections at various levels, all of which were successfully passed with repeated recognition. Relying on its mature and standardized clinical trial pharmacology base, the department has conducted numerous international and domestic multicenter clinical trials, including the development of many novel anti-tumor drugs, positioning it among the leading hematology departments in comprehensive hospitals. Several drugs from clinical studies previously participated in by the department have now received marketing approval, benefiting more patients with hematological malignancies, including daratumumab, bortezomib injection, bendamustine, azacitidine, eltrombopag, ibrutinib, zanubrutinib, obinutuzumab, and carfilzomib, among others. In 2011, the department participated in "A Randomized, Double-Blind, Placebo-Controlled Study Comparing the Efficacy and Safety of CNTO 328 (Anti-IL-6 Monoclonal Antibody) Combined with Best Supportive Care versus Best Supportive Care Alone in Subjects with Multicentric Castleman's Disease," serving as the study site with the highest global enrollment and successfully passing international audits. This drug (siltuximab for injection) was approved in China in December 2021 for the treatment of adult patients with multicentric Castleman's disease who are negative for human immunodeficiency virus (HIV) and human herpesvirus type 8 (HHV-8), and was among the first batch of urgently needed overseas new drugs. On April 1, 2022, the CDE website announced that the study our department is participating in—"CD19-Targeted Chimeric Antigen Receptor T Cells JWCAR029 (CD19-targeted chimeric antigen receptor T cells) by Shanghai Mingju Biotechnology Co., Ltd. for the treatment of adult patients with relapsed/refractory mantle cell lymphoma who have received two or more lines of therapy"—has been included in the "Breakthrough Therapy" designation, bringing hope to more patients with mantle cell lymphoma in the future. Over the past five years, our department has participated in the development of numerous guidelines, standards, and expert consensus documents, and has contributed to the compilation of multiple books, standardizing clinical experience while enhancing the department's influence within the field. Through years of conducting the aforementioned clinical research, the Department of Hematology has further strengthened its overall disciplinary competitiveness and consolidated its leading position in the field of hematology. In recent years, the Department of Hematology has further dedicated itself to clinical cohort construction research, which is of great significance for enhancing overall disciplinary development. To date, five large-scale cohort studies have been established: mantle cell lymphoma, follicular lymphoma, T-lymphoblastic lymphoma, multiple myeloma, and chronic lymphocytic leukemia/small B-cell lymphoma. Among these, a bidirectional cohort for mantle cell lymphoma has been established based on 19 centers in the northern region, with a case database and patient specimen bank of over 840 individuals established, with regular follow-up to maintain the database's timeliness. This currently represents the largest and most comprehensive mantle cell lymphoma database in northern China. The mantle cell lymphoma cohort study has received support from the Peking University Third Hospital Clinical Key Project. In relapsed/refractory mantle cell lymphoma, our department has led or participated in 9 clinical studies and received support from 7 national, provincial, and ministerial-level funding projects. The follicular lymphoma cohort study currently includes 3 centers with over 600 patients enrolled, and is currently conducting clinical model analysis and molecular biological analysis, establishing a patient education group for follicular lymphoma and participating in multiple clinical studies on follicular lymphoma. T-lymphoblastic lymphoma is a highly aggressive clinical tumor with an extremely poor prognosis, and the optimal treatment approach for adult hematopoietic stem cell transplantation remains unclear. A multicenter cohort study has been established to investigate the optimal treatment for adult T-lymphoblastic lymphoma, with prospective clinical studies led by our department exploring novel salvage treatment regimens for relapsed/refractory T-lymphoblastic lymphoma. The myeloma cohort study was jointly established by the Department of Hematology and the Department of Orthopedics, representing a typical multidisciplinary team (MDT) cohort within the hospital, with regular MDT activities conducted to analyze specific cases, promoting improvements in diagnosis and treatment levels and disciplinary development. Chronic lymphocytic leukemia/small B-cell lymphoma follows an indolent clinical course, and the chemotherapy-free treatment paradigm in the era of novel agents has introduced entirely new treatment concepts, with more patients completing diagnosis and treatment in outpatient settings. The establishment and follow-up of the outpatient cohort have facilitated comprehensive whole-process management of patient care. Through cohort construction, subspecialty directions have been developed, further deepening understanding of specific disease subtypes, which greatly contributes to and promotes the enhancement of overall disciplinary competitiveness.