From the Guidelines
Carcinoid syndrome symptoms include facial flushing, diarrhea, abdominal cramping, wheezing, and heart valve problems, and patients experiencing these symptoms, especially flushing and diarrhea together, should seek medical evaluation promptly for proper diagnosis and treatment. The symptoms of carcinoid syndrome result from hormones, primarily serotonin, released by carcinoid tumors, which are slow-growing neuroendocrine tumors usually found in the digestive tract or lungs 1. These symptoms can be triggered by various factors, including alcohol, spicy foods, or stress, and can lead to complications such as heart valve damage over time, particularly affecting the right side of the heart 1. Other symptoms include skin lesions called telangiectasias, fatigue, weight loss, and heart palpitations, and the syndrome typically occurs when tumor cells metastasize to the liver, allowing hormones to enter the systemic circulation without being metabolized first by the liver 1. Some key points to consider in the diagnosis and treatment of carcinoid syndrome include:
- The measurement of 5-hydroxyindoleacetic acid (5-HIAA) in 24-hour urine collections to diagnose carcinoid syndrome, with a specificity of close to 90% 1
- The use of somatostatin analogs, such as octreotide or lanreotide, to control symptoms and tumor growth in patients with metastatic NETs and carcinoid syndrome 1
- The potential use of telotristat or telotristat ethyl to treat persistent diarrhea in patients with carcinoid syndrome, as recommended in the NCCN Guidelines 1
- The importance of seeking medical evaluation promptly for proper diagnosis and treatment, as the symptoms of carcinoid syndrome can be similar to those of other conditions, and early diagnosis and treatment can improve outcomes and quality of life 1. According to the most recent and highest quality study, the therapeutic approach in NETs with carcinoid syndrome should prioritize somatostatin analogs, such as octreotide or lanreotide, and consider other treatment options, such as telotristat or telotristat ethyl, for symptom control and tumor growth 1.
From the FDA Drug Label
Other symptoms of carcinoid syndrome (abdominal pain or flushing) did not show improvement in the comparison of Xermelo to placebo The symptoms of carcinoid syndrome include:
- Diarrhea
- Abdominal pain
- Flushing These are the symptoms mentioned in the provided drug labels.
From the Research
Carcinoid Syndrome Symptoms
The symptoms of carcinoid syndrome include:
- Flushing
- Diarrhea
- Abdominal pain
- Wheezing 2
- Depression, anxiety, and cognitive impairment are also frequently present symptoms in patients with carcinoid syndrome 2
Treatment Options
Treatment of carcinoid syndrome focuses on reducing serotonin levels with:
- Somatostatin analogues (SSA's) 3, 4, 5, 2, 6
- Telotristat ethyl, an oral inhibitor of tryptophan hydroxylase, the rate-limiting enzyme in serotonin biosynthesis 3, 4
- Interferon-alpha, a cytokine with direct inhibitory effect on hormone secretion and tumor cell proliferation 3, 4, 5
- Peptide receptor radionuclide therapy (PRRT) 2
Efficacy of Treatment Options
- Somatostatin analogues induced symptomatic improvement in 65-72% and biochemical response in 45-46% of patients 4
- Telotristat ethyl reduced bowel movements in 40% of patients with diarrhea refractory to somatostatin analogs 4
- Interferon-alpha controlled carcinoid syndrome symptoms in 45-63% of cases 4
- Octreotide treatment reduced flush and/or diarrhea in 70% of patients, and 37% showed > 50% decrease in urinary 5-HIAA 5