What studies are appropriate and necessary for staging gastric adenocarcinoma? Results of an international RAND/UCLA expert panel

Background: The approach for staging gastric adenocarcinoma (GC) has not been well defined, with heterogeneity in the application of staging modalities. Methods: Utilizing a RAND/UCLA appropriateness methodology (RAM), a multidisciplinary expert panel of 16 physicians scored 84 GC staging scenarios. Appropriateness was scored from 1 to 9. Median appropriateness scores from 1 to 3 were considered inappropriate, 4-6 uncertain, and 7-9 appropriate. Agreement was reached when 12 or more of 16 panelists scored the scenario similarly. Appropriate scenarios were subsequently scored for necessity. Results: Pretreatment TNM stage determination is necessary. Necessary staging maneuvers include esophagogastroduodenoscopy (EGD); biopsy of the tumor; documentation of tumor size, description, location, distance from gastroesophageal junction (GEJ), and any GEJ, esophageal, or duodenal involvement; if an EGD report is unclear, surgeons should repeat it to confirm tumor location. Pretreatment radiologic assessment should include computed tomography (CT)-abdomen and CT-pelvis, performed with multidetector CT scanners with 5-mm slices. Laparoscopy should be performed before resection of cT3-cT4 lesions or multivisceral resections. Laparoscopy should include inspection of the stomach, diaphragm, liver, and ovaries. Conclusions: Using a RAM, we describe appropriate and necessary staging tests for the pretreatment staging evaluation of GC, as well as how some of these staging maneuvers should be conducted.