Rectal carcinoids are on the rise: early detection by screening endoscopy

Abstract

Rectal carcinoids are on the rise; in the United States the age-adjusted incidence has increased by 800% -1000% in the last 35 years. The incidence of carcinoids of the stomach, pancreas, or small bowels has also multiplied. The reasons for these epidemiological changes are not yet understood. Both screening sigmoidoscopy and screening colonoscopy lead to a shift to smaller-sized (< or =13 mm) rectal carcinoids and earlier tumor stages at diagnosis. During the last 35 years the overall 5-year survival of patients with rectal carcinoid disease has increased by almost 20% (in the US). Thus, endoscopic screening of the colorectum is effective in the early diagnosis not only of colorectal adenomas and adenocarcinomas but also of carcinoids. Rectal carcinoids that are 10.0 mm or less and do not infiltrate the muscularis propria can be removed endoscopically. If histological angioinvasion or lymph node metastases are found, surgical lymph node dissection has to be considered. Before deciding on definitive therapy, rectal carcinoids should be staged by means of endoscopic ultrasonography, CT, or MRI and somatostatin receptor scintigraphy.