The current landscape and advances in functional-preserving gastric cancer surgery.

With the gradual enhancement of public health literacy and advancements in gastroscopy technology, China has witnessed a steady increase in the detection rate of early-stage gastric cancer. Early-stage gastric cancer is characterized by favorable prognoses and prolonged survival times. In the treatment of early-stage gastric cancer, maintaining postoperative quality of life while ensuring curability without excessive intervention is crucial and remains a focal point in current therapeutic strategies. This can be addressed through minimally invasive, function-preserving gastrectomy. Laparoscopic proximal gastrectomy, pylorus-preserving gastrectomy, segmental gastrectomy, local gastrectomy, and laparoscopic-endoscopic combined surgery are all examples of function-preserving procedures. In proximal gastrectomy, reconstruction typically involves anti-reflux techniques such as esophagogastrostomy, double-tract reconstruction, and jejunal interposition. Currently, the Kamikawa anastomosis, as a method to prevent reflux esophagitis, has become the preferred reconstruction technique in Japan. However, a standardized reconstruction method following proximal gastrectomy has yet to be established. Additionally, sentinel lymph node navigation surgery is essential for maintaining the curability of early-stage gastric cancer through minimally invasive, function-preserving gastrectomy. It aids in intraoperative lymph node localization, assesses lymph node metastasis, and determines the extent of lymphadenectomy, thereby enhancing postoperative quality of life for early-stage gastric cancer patients. Internationally, sentinel lymph node navigation surgery has been established as a treatment option for specific early-stage gastric cancer patients, with its application expected to expand in the future. This article reviews the current research status of function-preserving gastrectomy for gastric cancer both domestically and internationally. It details various function-preserving surgical methods, analyzes and summarizes their clinical efficacy, aiming to provide valuable references for surgeons to better perform such surgeries. This, in turn, will promote the standardized application and further development of function-preserving gastrectomy for gastric cancer in clinical practice. Keywords: Gastric Cancer; Functional-Preserving Surgery; Gastrectomy; Digestive Tract Reconstruction；Surgical treatmentIntroduction According to the 2022 Global Cancer Statistics released by the International Agency for Research on Cancer of the World Health Organization, GC ranks 5th in incidence and 4th in mortality globally [1]. Traditional surgical complications, such as postoperative malnutrition, anemia, and inadequate anti-reflux, significantly impact patients' quality of life. Therefore, reconstructing the anti-reflux barrier and preserving the residual stomach's function during surgical treatment are critical concerns. In recent years, functional preservation surgeries for GC have gained traction, aiming to retain part of the stomach's anatomical and physiological functions while ensuring radical tumor resection, thereby enhancing postoperative quality of life [2]. In functional-preserving gastrectomy, precise assessment of lymph node metastasis status is crucial for determining surgical approaches, predicting prognosis, and guiding subsequent treatments, requiring a balance between tumor radicality and functional preservation. Lymph node metastasis is a pivotal biological behavior in malignant tumor progression, involving tumor cells detaching from the primary site, colonizing lymph nodes via the lymphatic circulation, and proliferating, resulting from interactions between tumor cells and the host microenvironment. The pathophysiological mechanisms involve complex multi-step, multi-factor regulation of tumor cell invasion, migration, and colonization. Diagnosis of lymph node metastasis necessitates clinical, imaging, and pathological methods, with pathological diagnosis serving as the "gold standard" ,including intraoperative frozen section biopsy of suspicious lymph nodes, postoperative paraffin-embedded cases, and sentinel lymph node biopsy. With advancements in molecular diagnostic technologies, future identification of micrometastases and potential metastatic risks will become more precise, providing stronger support for assessing lymph node metastasis. Currently, widely used functional-preserving surgeries include proximal gastrectomy(PG), pylorus-preserving gastrectomy(PPG), segmental gastrectomy(SG), local gastrectomy(LG), and laparoscopic-endoscopic combined surgeries(LECS).