CARCINOID TUMORS.

Carcinoid tumors are diminutive growths found along the gastrointestinal tract, in the lungs and, occasionally, within the confines of teratomas. Carcinoid tumors of the intestinal tract are found in decreasing order of frequency in the rectum, the appendix, the ileum, the jejunum, the lung, the stomach and the duodenum. Arising from argentaffin elements in the crypts of Lieberkuehn, and secreting serotonin, carcinoid tumors belong to the order of functioning neoplasms. Their indolent growth seems to place them between benign neoplasms and carcinomas. However, they possess propensities for metastasis that correlate with increase in size. The symptoms that are produced are almost always due to the presence of metastatic lesions. In ileal and gastric carcinoid tumors, the tendency to metastasis is augmented and the metastatic masses are sometimes of sufficient bulk to cause the carcinoid syndrome or to interfere with the supply of blood to the affected segment. More often they produce the clinical picture of intestinal obstruction. The unusually long interval from onset to death associated with carcinoid tumors makes palliative subtotal resections and short-circuiting operations in symptomatic patients with advanced disease worthwhile, for by such unorthodox procedures the patients may be afforded many additional years of useful life.