Ratio of metastatic lymph nodes on resected lymph nodes as a prognostic factor in gastric Cancer

• Grant number: 21/13897-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: May 01, 2022
• End date: April 30, 2023
• Field of knowledge: Health Sciences - Medicine - Surgery
• Principal Investigator: Ulysses Ribeiro Júnior
• Grantee: Breno Cordeiro Porto
• Host Institution: Instituto do Câncer do Estado de São Paulo Octavio Frias de Oliveira (ICESP). Coordenadoria de Serviços de Saúde (CSS). Secretaria da Saúde (São Paulo - Estado). São Paulo , SP, Brazil

Abstract

Gastric cancer (GC) is one of the most frequent neoplasms in the world, ranking as the 5th most incident, and the 4th in mortality. In 2020, this disease affected 1,089,103 people, of which 21,230 were new cases in Brazil. The most common histological type is adenocarcinoma, responsible for about 95% of cases of stomach cancer. Most patients are diagnosed at an advanced stage, where gastrectomy, with D2 lymphadenectomy, is the gold standard surgery with curative intent in locally advanced GC. The presence of metastasis in lymph nodes (LNs) is the main prognostic factor in GC, and the number of LNs affected is directly associated with patient survival. Thus, an adequate lymphadenectomy is essential to reduce the chances of metastasis dissemination through the lymphatic route and to verify the correct tumor stage. However, in many cases, the number of resected LNs is not sufficient for a reliable assessment of the pN category, which can lead to understating. Thus, a more adequate prognostic parameter, regardless of the extent of lymphadenectomy or the number of LNs evaluated, would be ideal for the correct assessment of these patients. In this context, the Lymph node ratio (LNR) - defined as the ratio between the number of positive LNs and the total number of removed LNs - has been reported as the most suitable method for the GC stage in comparison to the pN stage, which considers only the number of positive LNs to determine the prognosis. However, the results presented and their impact on survival is still controversial. Thus, the present study proposes to investigate the prognostic value of the LNR parameter in patients with gastric cancer undergoing surgical treatment with curative intent, in addition to evaluating the role of this measure in different scenarios depending on the number of resected LNs, to establish a comparison of the survival provided by the LNR with that of the pN stage and to establish correlations between LNR and other clinicopathological parameters.(AU)