ROGCAS - Retrospective Observational Gastric Cancer Study

This is an observational retrospective research entitled "Gastric cancer endoscopic screening in an intermediate-risk country - ROGCAS, a dual-centre pilot program" (STROBE protocol. This study will analyze the results of an initiative of the ULSAALE Endoscopy Units, which, with the approval of the Board of Directors and Ethics Committee, started an opportunistic screening pilot program for oesophagogastric cancer in February 2023, inviting users from the national colorectal screening program to undergo EGD at the same time as screening colonoscopy. Based on the assumptions of the theoretical models of cost-effectiveness studies, we will analyze the efficacy of endoscopic screening for GC by determining the HP infection rate, the pre-malignant lesion detection rate, the GC detection rate, the early GC detection rate, the stage at diagnosis, the adherence rate and the cost of this pilot program. This study will be carried out in the Endoscopy Units of Hospital Doutor José Maria Grande and Hospital de Santa Luzia de Elvas, with the approval of the Board of Directors and the Ethics Committee of ULSAALE, and data will be collected by consulting the Sclinico records of patients who agree to participate in the study and who have undergone EGD and screening colonoscopy at the same time in these hospitals. In terms of potential benefits, this study could help to elucidate the appropriateness of introducing endoscopic GC screening at the same time as colorectal cancer screening in order to detect pre-malignant and malignant lesions at an earlier stage, thus improving the management and prognosis of this pathology.

On the other hand, users can undergo two endoscopic screenings simultaneously with the same sedation, saving time and resources and reducing the number of referrals to health centers. In terms of risks, there are those associated with endoscopic procedure and those associated with the screening process. As for complications, although rare, bleeding, perforation and infection have been described, but ULSAALE has expert teams of gastroenterologists and surgeons to deal with these complications. There are also risks associated with the sedation process, related to local and systemic pharmacological reactions and the possible need for ventilatory support, which is why an anaesthesiologist and/or an advanced life support team is always present. The risks of the screening program itself are related to false positive results and overdiagnosis. False positives, in addition to the potential psychological damage to the patient, lead to unnecessary diagnostic investigations and consumption of resources. Overdiagnosis, on the other hand, could place a burden on health services, both in terms of surveillance of premalignant lesions and in terms of providing timely treatment to patients diagnosed with GC. However, since this is a pathology with a high incidence and mortality rate in Portugal, the benefits of early diagnosis and improved prognosis seem to outweigh the inherent risks of the endoscopic screening program. Participation in this study is also voluntary and all participants will be asked to give informed consent after receiving adequate information and personal reflection.