A 57 year old female had a tubular gastric adenocarcinoma confirmed by endoscopy and radiologic studies. Echotomography of the abdomen revealed multiple adenopathies. Immunoscintigraphy with 99mTc labeled anti-CEA BW 431/26 monoclonal antibody was performed. Images obtained at 6 and 24 h showed a significant uptake at the primary lesion and at periaortic adenopathies both in conventional gamma-camera and single emission photon tomography. This immuno-scintigraphic technique may be helpful in the management of patients with gastric cancer.