Karzinoid

Karzinoid refers to a type of slow-growing tumor that arises from neuroendocrine cells. These cells are found throughout the body, but karzinoids most commonly develop in the gastrointestinal tract, particularly in the appendix, small intestine, and rectum, and also in the lungs. Despite their name, not all karzinoids are malignant, though they have the potential to metastasize.

The term "karzinoid" itself means "cancer-like." These tumors often secrete hormones, such as serotonin, which can lead to a range of symptoms. The most well-known manifestation of hormone secretion from a karzinoid tumor is carcinoid syndrome. Symptoms of carcinoid syndrome can include flushing of the skin, diarrhea, abdominal cramps, wheezing, and heart valve problems. However, many karzinoid tumors, especially those in the appendix and rectum, do not produce enough hormones to cause noticeable symptoms and are often discovered incidentally during other medical procedures.

Diagnosis typically involves imaging tests like CT scans or MRIs, along with blood or urine tests to measure hormone levels. Biopsy and histological examination of the tumor tissue confirm the diagnosis. Treatment depends on the tumor's location, size, whether it has spread, and the presence of symptoms. Options can include surgical removal of the tumor, medication to manage hormone overproduction, and, in some cases, therapies to control tumor growth. Prognosis is generally favorable for early-stage, localized karzinoids, especially when completely removed surgically.