Carcinoid Tumors Are Often Misdiagnosed as IBS

The early symptoms of carcinoid tumors are difficult to recognize. Carcinoid tumors are frequently misdiagnosed as irritable bowel syndrome (IBS) for many years before the correct diagnosis becomes apparent.

Carcinoid tumors are a solid malignant cancers that arise from neuroendocrine cells found dispersed throughout the body. Approximately 66% of carcinoid tumors originate in the gastrointestinal system.

Carcinoid tumors that originate in the intestines begin deep in the intestinal mucosa lining the inner lumen of the intestines. These solid carcinoid tumors grow slowly and extend into the deeper underlying submucosa and out into the mucosal surface.

All carcinoid tumors have the potential to metastasize (send cancerous cells). Malignant carcinoid tumors can metastasize to other sites in the body. For example, carcinoid tumors in the small intestine most frequently metastasize to the liver.

The early signs and symptoms associated with gastrointestinal carcinoid tumors are usually quite vague. The symptoms often resemble other disorders of the gastrointestinal tract such as irritable bowel syndrome and inflammatory bowel disorders.

The most common misdiagnosis in individuals who have early symptoms of carcinoid tumors is irritable bowel syndrome or IBS. The symptoms of IBS include alternating diarrhea and constipation as well as abdominal pain relieved with bowel movements.

The most frequent early signs and symptoms of carcinoid tumors include:

-Abdominal pain

-Rectal bleeding

-Intestinal obstruction

-Constipation

-Diarrhea

-Abdominal mass

-Bleeding from the GI tract

Theses neuroendocrine tumors also have the potential to secrete bioactive substances into the circulation. The secretion of hormones and biopeptides, such as serotonin, histamine and tachykinins, by the malignant carcinoid cells can result in specific symptoms known as Carcinoid Syndrome.

Individuals may display a spectrum of the carcinoid symptoms below. However, the most frequently reported symptoms of carcinoid syndrome are episodes of flushing and diarrhea.

Common symptoms of Carcinoid Syndrome include:

-Cutaneous flushing (episodic red flush of the skin)

-Diarrhea

-Carcinoid heart disease (valvular disease)

-Bronchospasms and wheezing

-Arthropathy (joint problems)

-Increased skin pigmentation

-Fibrosis

It can take several years for a carcinoid tumor to progress to the more recognizable symptoms of carcinoid syndrome. In fact, patients who present with vague or nonspecific abdominal symptoms can often go 5 to 7 years before receiving an accurate diagnosis.

The delay in a correct diagnosis for carcinoid tumors is frequent and particularly discouraging when considering that the incidence of carcinoid tumors is increasing in the United States. Approximately one out of every 100,000 people was estimated to have a carcinoid tumor in 1980, whereas this estimate had increased to five out of every 100,000 people by the year 2000.