karzinoids

Carcinoids are a type of slow-growing neuroendocrine tumor. They can arise in various parts of the body, most commonly in the digestive tract, lungs, and ovaries. The term "carcinoid" was originally coined by the pathologist Rudolf Oberndorfer in 1907, reflecting his observation that these tumors shared some characteristics with carcinomas but were also distinct.

Neuroendocrine tumors, including carcinoids, originate from cells that have characteristics of both nerve cells and endocrine (hormone-producing) cells. These cells are found throughout the body, playing roles in various functions. When these cells undergo abnormal growth, they can form a carcinoid tumor.

Many carcinoid tumors do not produce any symptoms, especially when small. When symptoms do occur, they are often related to the hormones the tumor may be secreting. For example, carcinoid syndrome can develop, characterized by symptoms such as flushing, diarrhea, wheezing, and heart valve problems. The specific symptoms depend on the location of the tumor and the hormones it releases.

Diagnosis typically involves imaging tests like CT scans or MRI, blood or urine tests to detect hormone levels, and biopsies. Treatment options vary depending on the tumor's size, location, grade, and whether it has spread. Surgery is often the primary treatment for localized carcinoid tumors. Medications can be used to manage hormone secretion and control symptoms. In some cases, other therapies like peptide receptor radionuclide therapy or chemotherapy may be employed. Carcinoids generally have a better prognosis than many other types of cancer due to their slow growth rate.