My dad 67 years old. Having stomach pain. Doctor did biopsy result : suggestive of adenocarcinoma ,moderately differentiated Ultrasound: shows enlarged retroperitoneal lymph nodes in the paraaortic and aortocaval station measuring upto 18mm to 12mm. Colonoscopy :shows ulceroproliferative  growth originating from ge junction to the lessser curvature of the stomach Which scan can be used to stage and find spread of cancer accurately?? Other than pet ct scan is there any other scan like taking upper and lower portion of the body?? Doctor was planing radiation and surgery. If doctor not doing pet scan is there other scan thats accurate?? Not sure which scan he will do. He just called us tomorrow.. Can doctor start treatment without staging??