Gastric cancer: Russian clinical guidelines

Gastric cancer remains one of the most common malignancies in Russia. Despite steady decrease of gastric cancer incidence it still reaches 24.65 per 100 000 population (crude rate) in 2019 with about 36 000 new cases annually. More than 29 000 people die of gastric cancer every year. High mortality rate is mostly caused by an extremely significant proportion of patients with metastatic disease which reached 40.1% in 2019. The majority of cases is related to Helicobacter pylori infection, salty diet, tobacco exposure as well as hereditary syndromes. Staging of locally advanced gastric cancer includes contrast-enhanced computed tomography of the thorax, abdomen and pelvis as well as diagnostic laparoscopy with peritoneal washings. In patients with inoperable or disseminated cancer of the stomach additional analysis for HER2, microsatellite instability and PD-L1 status is recommended. Endoscopic or laparoscopic resection remains the mainstay of treatment in patients with early cancer. Laparoscopic gastrectomy in patients with locally advanced cancer is reserved for high-volume centers with extensive experience with the procedure. Recently, perioperative cytotoxic therapy became the standard of treatment in patients with locally advanced gastric cancer. FLOT regimen is recommended while FOLFOX6 or XELOX are considered possible in the elderly or frail patients. Drug therapy includes standard doublet or triplet chemotherapy regimens for metastatic disease with trastuzumab for HER2(+++) patients. Patients with MSI-H tumors can be treated with pembrolizumab starting with 2nd line while nivolumab is reserved for the 3rd and further lines regardless of PD-L1 status. Importantly, this year guidelines include multimodal prehabilitation including physical exercise, nutritional support and psychological counselling as a possibility in all patients in need of surgery. Also standardized enhanced recovery protocols are recommended for usage during the perioperative period.