Outstanding issues in perioperative chemotherapy for gastric cancer

Gastric cancer is an important medical and social problem all over the world. The aggressiveness of the course of this disease is reflected by the high figures of one-year mortality, which is due to both high neglect at the time of diagnosis and unsatisfactory results of surgical treatment of even a localized tumor process, which from a biological point of view casts doubt on the possibility of performing a “radical” operation for this type of malignant tumor. Currently, the “gold standard” has become the conduct of perioperative chemotherapy according to the FLOT scheme for locally advanced stages of gastric cancer, esophagogastric junction and esophagogastric junction and lower esophagus. A further promising direction for improving perioperative chemotherapy is the investigation of immune checkpoint inhibitors (pembrolizumab, atezolizumab and durvalumab) in combination with cytostatics. Today, there are still a number of unresolved issues, including the need to continue such aggressive treatment in the postoperative period with an unsatisfactory pathomorphological response from the tumor. Performing the entire volume of chemotherapy is a difficult task, due to the toxicity of this type of treatment and the weakened condition of the patient after extensive surgery. The significance of the pathomorphological regression of the tumor after neoadjuvant chemotherapy is also unclear. Only 10–15% of patients achieve a complete pathomorphological response. The standard postoperative practice is to carry out the same preoperative chemotherapy regimen, regardless of sensitivity to it. The search for prognostic markers will help to individualize the treatment strategy of such patients and protect patients from excessive toxicity with unjustified continuation of chemotherapy.