Measuring intragastric tumor markers in gastric cancer patients: a systematic literature review on significance and reliability

As of 2017, no serum tumor marker has shown high levels of sensitivity or specificity for early detection, classification, staging, prediction and prognosis of patients affected by gastric cancer. In this regard, since 1975 several authors have investigated the gastric juice or gastric lavage of patients with gastric adenocarcinoma in order to determine the concentrations of intragastric tumor markers and discover the perfect antigen for this cancer. To date, however, a systematic review of the literature on intragastric tumor markers is still unreported. After a thorough search, we found important as well as unimportant findings and have come to clearly defined conclusions. We believe that describing the current state of knowledge achieved by the scientific community in this particular field of research could augment information on the complex pathobiology of gastric cancer and entail a deeper understanding of its unpredictable malignant behavior.