[Historical Background]

The Department of Pathology at Zhongshan Hospital has a rich and illustrious history, dating back to the hospital's inception. It is closely linked with the Pathology Department of the original Shanghai Medical College (later Shanghai Medical University), and renowned national experts in pathology such as Gu Jingqian and Gu Suiyue, among others, provided a solid foundation for the development of clinical pathology at Zhongshan Hospital. In 1957 and 1973, Zhongshan Hospital assigned Professors Chen Changchun and Pan Wensheng from the General Surgery Department to lead the surgical pathology diagnostic work. In 1989, a pathology laboratory was established to meet the needs of research. In the 1990s, in line with the hospital's development, the department was officially established in 1992, and the pathology laboratory was subsequently renamed the Department of Pathology. In February 2001, to comply with standardized management requirements, the cytopathology unit returned from the Laboratory Medicine Department to the Department of Pathology. Under the prospective leadership of successive department heads, including Professors Chen Changchun, Pan Wensheng, and Tan Yunshan, the Department of Pathology gradually expanded. Currently, the baton has been passed on to Director Hou Yinghong. After 30 years of hard work. With the care and support of hospital leadership over the years, the Pathology Department at Zhongshan has made significant progress and, as of 2022, has grown to become a department with 36pathologist, 39 technicians, and a comprehensive medical practice, educational, and research combination. The department occupies a workspace of approximately 1500 square meters, featuring a well-organized layout and standardized processes. As the department has evolved, it has developed four main sections: Organ Pathology, Immunopathology, Molecular Pathology, and Cytopathology. Additionally, it participates in the establishment of the hospital's tissue bank and collaborates with some branch hospitals to establish a network pathology cooperative platform. The department is also involved in the construction of a national telepathology consultation system.

[Personnel Composition]

The Department of Pathology has 11 senior title pathologist, including the current department head, Professor Hou Yinghong, Vice Professors Ji Yuan and Lu Shaohua. Among them, 7 have full professorships, and 4 have associate professorships. Three of the senior pathologist are doctoral supervisors (Hou Yinghong, Chen Gang, Lu Shaohua), and five are master's supervisors. The department has 20 attending physicians and 5 resident. Notably, 20 of the staff hold doctoral degrees (55.5%), and 15 hold master's degrees (41.7%). In 2022, the Department of Pathology is training 6 attending physicians in the Clinical Pathology Specialty Base program, and 31 resident in the standardized training program for pathologists. Within the technical group, there are 3 associate chief technicians, 10 supervising technicians, and 26 technicians. Among them, 3 hold doctoral degrees, and 14 have master's degrees (accounting for 43.6%). There are approximately 15 personnel in other assisted roles.

[Routine Work]

The Department of Pathology at Zhongshan Hospital has witnessed significant growth in its workload over the years. At its establishment, it processed nearly 20,000 cases per year. In 2014, it surpassed 100,000 cases, and in 2021, it handled nearly 200,000 cases. The department performs over 13,000 frozen sections annually, more than 17,000 rapid pathological diagnoses, and approximately 7,000 consultation cases. It offers nearly 300 kinds of immunohistochemistry tests, performing over 30,000 of these tests each year, as well as around 25,000 special staining procedures. In 2022, the cytopathology section exceeded 40,000 diagnoses. The department is known for its diverse range of pathology specimens, including surgical resections, biopsies, endoscopic biopsies, EMR/ESD samples, fine needle aspirations, and more, covering a wide range of tumor and non-tumor lesions in various organ systems. These include but are not limited to hepato-biliary, cardio-thoracic, gastrointestinal, breast, head and neck, urological, and gynecological systems, as well as soft tissues and hematolymphoid disorders. The department has also seen rapid growth in transplant pathology, particularly in liver transplantation. Pathologists are skilled in diagnosing and differentiating various benign and malignant conditions, and they actively participate in the diagnosis and treatment process of patients through numerous multidisciplinary team (MDT) collaborations.

[Molecular Pathology]

In the field of Molecular Pathology, the department began its journey in 2003 by conducting KIT and PDGFRA gene testing for gastrointestinal stromal tumors. In 2006, it received the First Prize of the New Technology and New Project from Zhongshan Hospital. After more than a decade of accumulating equipment and personnel, the department established a clinical PCR laboratory that complies with the "Basic Settings Standard for Clinical Gene Amplification Testing Laboratories." It strictly adheres to clinical gene amplification laboratory work and management standards to provide strong evidence-based support for clinical diagnosis and treatment. The Molecular Pathology Laboratory was consecutively selected as a demonstration laboratory by the Pathology Quality Control and Competence Center (PQCC) of the National Health and Family Planning Commission for three terms (2015, 2017, 2019). In 2014, it successfully obtained qualification as one of the first national high-throughput testing centers for "Cancer Diagnosis and Treatment." In its daily work, the department conducts various molecular pathology tests that are applicable to pathology diagnosis and targeted therapy. This includes gene mutation testing for KIT, PDGFRA, K-ras, N-ras, B-raf, PIK3CA, EGFR, and more. It also performs IgH and TCR gene rearrangement tests and conducts CISH or FISH testing for genes such as EBER, HER2, SS18, bcl-2, bcl6, c-myc, MALT, EWS, MDM2, CDK4, DDIT3, CCND1, MET, EGFR, Urovysion, PIK3CA, FOXO1, FUS, P53, D13S319, D13S25, RB1, 1q21, ATM, CSP12, ALK, ROS1, and many more, with the capability to conduct high-throughput testing for different gene combinations. The department actively participates in interlaboratory quality control programs, both nationally and internationally, and successfully passes these assessments.

[Teaching Activities]

The Department of Pathology became a master's degree training site in 1995, a doctoral degree training site in 2013, and was granted a post-doctoral training site for clinical pathology by Zhongshan Hospital in 2019. In 2007, it was approved as a key discipline by the National Ministry of Education (in conjunction with Fudan University Shanghai Medical College's Pathology Department). In 2010, it became one of the first training centers for pathological resident in Shanghai, and in 2014, it became one of the first specialized training centers for clinical pathology in Shanghai, offering specializations in general

pathology, thoracic pathology, digestive system pathology, and lymphatic system pathology. In 2018, it was recognized as the backbone training base for clinical pathologists by the Chinese Medical Association. In 2019, it became a clinical key specialty and a clinical medical research center in Shanghai. In 2021, it received recognition as a key specialty base for standardized training for pathological resident by the Chinese Medical Association. Over the years, the department has consistently organized national-level continuing education courses, providing comprehensive training in various aspects of pathology, including fine needle aspiration, intraoperative frozen section diagnosis, and the role of pathology in multidisciplinary team-based patient care. The department is responsible for teaching clinical pathology to various groups of students, including pathological residents, rotating residents, clinical interns from different departments. It trains 3-6 recruited pathology residents per year, 6-9 graduate students (including residents pursuing specialty certifications) per year, 9-12 rotating residents, and nearly a hundred clinical interns. Resident physicians are trained through a mentorship system, with each being paired with a senior pathologist for one-on-one guidance. The department boasts a wealth of teaching resources and a strong teaching team. Its advanced equipment and various state-of-the-art pathology technologies provide an excellent platform for training resident physicians.

[Research and Publications]

The Department of Pathology has received 16 grants from the National Natural Science Foundation of China and over 10 grants from the Shanghai Municipal Science and Technology Commission and the Shanghai Municipal Health Commission. The department has published research articles in renowned international journals such as Nature Medicine (IF: 53.44), American Journal of Respiratory and Critical Care Medicine (IF: 21.4), Advanced Science (IF: 16.8), Journal of Thoracic Oncology (IF: 15.6), Nature Communications (IF: 14.9), Oncogene (IF: 9.86), Modern Pathology (IF: 7.8), Laboratory Investigation (IF: 5.662), Histopathology (IF: 5.087), among others. In addition to international publications, the department has also published numerous articles in well-known Chinese journals such as the Chinese Journal of Pathology and the Chinese Journal of Transplantation. The department has made significant contributions to the establishment of several clinical practice guidelines, including the World Health Organization classification of lung cancer and thymic tumors, national standards for dust lung pathology diagnosis, and participation in the development of expert consensus documents, such as the "Chinese Gastrointestinal Stromal Tumor Diagnosis and Treatment Consensus" and "Chinese Expert Consensus on Epidermal Growth Factor Receptor Gene Mutation Testing in Non-Small Cell Lung Cancer Patients." Moreover, the department has edited and contributed to several textbooks and reference books, including "Gastrointestinal Stromal Tumors," "Liver, Gallbladder, and Pancreatic Tumors - Pathology, Imaging, and Clinical Aspects," and has participated in the translation of multiple specialized publications. The department has been involved in the identification of various technological achievements and has received several awards, including second and third prizes for scientific and technological progress in Shanghai.

(Note: The impact factors of journals are referenced to information available in 2021.)