Investigator propose the implementation of circulating biomarker monitoring, focusing on molecules related to the progression of gastric atrophy and/or associated with gastric cancer.

Monitoring these biomarkers will provide gastroenterologists with timely information on individuals at risk and, if values worsen during follow-up, will alert physicians observing these patients to evaluate them.

This monitoring will be offered to individuals who contact the IBO (Immunopatologia e Biomarcatori Oncologici) Unit at CRO (Centro di Riferimento Oncologico) in Aviano requesting an assessment of gastric function through pepsinogen and G17 gastrin level testing. Monitoring these biomarkers will provide a dynamic analysis of patients' gastric status, allowing for timely intervention in case of deviations from normal values. This proactive approach is important for the preventive management of gastric diseases, particularly for the diagnosis and monitoring of gastric atrophy and gastric cancer.

The IBO unit of the CRO in Aviano, together with the pathological anatomy and clinical units of gastroenterology, medical oncology, and surgery, will play a role in coordinating and implementing this monitoring program, thus contributing to the promotion of gastric health and the prevention of associated diseases.

Inclusion Criteria:

• Aged over 18;
• Ability to understand, accept, and sign the informed consent form for the study;
• Ability to understand, accept, and sign the consent form for data processing;
• Ability to understand, accept, and sign the consent form for the collection of a serum sample for research purposes;
• Patients who are fasting and have requested a pepsinogen test or gastroscopy, or who have gastric cancer prior to treatment;
• Subjects who are fasting and have suspected pre-neoplastic/neoplastic gastric lesions or who have requested a pepsinogen test and for whom endoscopic examination data are available.

Exclusion Criteria:

• Patients under the age of 18
• Pregnant women
• Patients with a coexisting or previous diagnosis of another malignant neoplasm in the last 5 years
• Patients unable to understand, accept, and sign the consent form for data processing

The study will be divided into two patient cohorts:

• a retrospective cohort comprising biological material (serum) stored at the IBO unit of the CRO in Aviano and/or at the Biobank since 2014 from subjects with suspected gastric lesions or gastric cancer;
• a prospective cohort of subjects with prescriptions for pepsinogen and G17 gastrin testing. Selection will be made from among those who present at the CRO blood collection room in Aviano, in gastroenterology, or who are admitted to medical oncology or surgery for gastric cancer. Hospitalized patients will undergo fasting blood sampling before therapy or surgery. Subjects belonging to high-risk categories or diagnosed with neoplasia will undergo a second blood sampling during follow-up to monitor any disease progression or therapeutic response.