类癌是一种生长缓慢的上皮细胞肿瘤 ,具有恶化的倾向。原发肿瘤常发生在胃肠道。恶性类癌可转移至肝脏 ,使血流中血清素等物质增多。所以 ,也有人认为是一种内分泌肿瘤。临床表现除局部症状外 ,还有皮肤潮红 ,腹泻 ,腹痛 ,哮喘 ,心脏瓣膜病变 ,以及水电解质失衡如低钾血症。此 Carcinoid carcinoid is a slowly growing epithelial tumor with a propensity to deteriorate. Primary tumors often occur in the gastrointestinal tract. Malignant carcinoid can be transferred to the liver, so that blood flow and other substances increased serotonin. Therefore, some people think that is an endocrine tumor. In addition to the clinical manifestations of local symptoms, there are skin flushing, diarrhea, abdominal pain, asthma, valvular heart disease, and water and electrolyte imbalance such as hypokalemia. this