From the Guidelines
Carcinoid tumors often present with symptoms such as abdominal pain, diarrhea, nausea, vomiting, rectal bleeding, or intestinal obstruction in gastrointestinal cases, and coughing, wheezing, chest pain, and recurrent lung infections in lung cases, with carcinoid syndrome characterized by facial flushing, diarrhea, wheezing, rapid heartbeat, and skin lesions occurring in about 1% to 5% of patients 1.
Symptoms of Carcinoid Tumors
The symptoms of carcinoid tumors vary depending on the tumor's location and whether it has spread.
- Gastrointestinal carcinoid tumors may cause:
- Abdominal pain
- Diarrhea
- Nausea
- Vomiting
- Rectal bleeding
- Intestinal obstruction
- Lung carcinoid tumors typically cause:
- Coughing
- Wheezing
- Chest pain
- Recurrent lung infections
Carcinoid Syndrome
As these tumors grow and spread, they can produce excess hormones leading to carcinoid syndrome, which is characterized by:
- Facial flushing
- Diarrhea
- Wheezing
- Rapid heartbeat
- Skin lesions Other possible symptoms include:
- Unexplained weight loss
- Fatigue
- In rare cases, heart valve problems due to hormone-induced fibrosis The diagnosis of carcinoid syndrome can be made by measuring the main metabolite of serotonin, 5-hydroxyindoleacetic acid (5-HIAA), in 24-hour urine collections, with a specificity of close to 90% 1.
Importance of Early Detection
If you experience persistent digestive issues, unexplained flushing, or breathing difficulties, seek medical attention as early detection improves treatment outcomes. The evaluation of patients with suspected carcinoid tumors should include imaging studies, such as CT and MRI, to assess disease burden and possible primary location, as well as biochemical evaluation, including a 24-hour urine collection for 5-HIAA, to evaluate serotonin secretion 1.
From the Research
Symptoms of Carcinoid Tumor
- The hallmark symptoms of carcinoid syndrome are flushing and diarrhea 2
- Atypical signs and symptoms can include:
- Wheezing
- Abdominal pain
- Valvular heart disease
- Telangiectasias
- Pellagra
- Complications of mesenteric fibrosis, including ureteral obstruction, bowel obstruction, and bowel ischemia 2
- Carcinoid syndrome can also present with difficult-to-control diarrhea and fibrotic complications, which significantly worsen the patient's quality of life 3
- Cutaneous flushing and diarrhea are the most typical clinical manifestations of midgut carcinoid in the presence of liver metastases 4
Biochemical Markers
- Serum chromogranin A is a nonspecific biochemical tumor marker for carcinoid tumors 4
- Increased urinary excretion of 5-hydroxyindole acetic acid (5-HIAA) is a specific marker for the carcinoid syndrome 4
- Fasting plasma 5-HIAA assay can be used as a convenient screening test for carcinoid, with a sensitivity of 89%, a specificity of 97%, and a test efficiency of 93% 5