From the Guidelines
Surgery is the primary treatment for localized carcinoid tumors, and somatostatin analogs are the first-line medical therapy for metastatic carcinoid tumors to control symptoms of carcinoid syndrome. Carcinoid tumors are rare, slow-growing neuroendocrine tumors that most commonly develop in the gastrointestinal tract, particularly the small intestine, rectum, and appendix, though they can also occur in the lungs and other organs. Treatment typically involves surgical removal of the tumor when possible, which is often curative for localized disease 1.
For metastatic carcinoid tumors, somatostatin analogs like octreotide are the first-line medical therapy to control symptoms of carcinoid syndrome such as flushing, diarrhea, and wheezing 1. These medications work by binding to somatostatin receptors on tumor cells, inhibiting hormone secretion. Additional treatments may include liver-directed therapies for hepatic metastases, targeted therapies like everolimus or peptide receptor radionuclide therapy (PRRT) with lutetium Lu 177 dotatate for progressive disease.
Regular monitoring with biomarkers (5-HIAA, chromogranin A) and imaging is essential, as these tumors can cause carcinoid heart disease through the release of serotonin and other vasoactive substances, potentially leading to right-sided heart valve problems that require cardiac evaluation and management 1. The 5-year survival rate for patients with localized disease is estimated to be 80–100%, while for metastatic disease, it is around 29% 1.
Some key points to consider in the management of carcinoid tumors include:
- Surgery is the primary treatment for localized tumors and might be curative giving 5-year survival rates of 80–100% 1
- Somatostatin analogs are the first-line treatment of carcinoid syndrome and may be considered as first-line systemic antiproliferative treatment in unresectable PCs, particularly of low-grade TC and AC 1
- Locoregional or radiotargeted therapies should be considered for metastatic disease 1
- Systemic chemotherapy is used for progressive PCs, although cytotoxic regimens have demonstrated limited effects with etoposide and platinum combination the most commonly used, however, temozolomide has shown most clinical benefit 1
From the Research
Definition and Characteristics of Carcinoid Tumors
- Carcinoid tumors originate from neuroendocrine cells throughout the body and are capable of producing various peptides 2.
- They can be found in various locations, with the most common sites being the gastrointestinal and respiratory tracts 3, 4.
- The clinical presentation of carcinoid tumors depends on location, aggressiveness, production of biologically active amines and peptides, paraneoplastic syndromes, and tendency for metastasis 3.
Imaging and Diagnosis of Carcinoid Tumors
- Cross-sectional and functional imaging plays an important role in diagnosis, lesion characterization, and staging of carcinoid tumors 3.
- Various imaging modalities can be used, including gastrointestinal studies, ultrasound, computed tomography, magnetic resonance imaging, and nuclear medicine studies (radioactive octreotide) 4, 5.
- The hypervascular nature of carcinoid tumors and their metastases allows for a more aggressive role by the radiologist in diagnosis and interventional management 5.
Treatment and Management of Carcinoid Tumors
- The only curative therapy for carcinoid tumors remains surgical resection 6.
- Management of patients with carcinoid tumors requires an understanding of the disease process and a multimodality approach 2.
- Introduction of long-acting somatostatin analogues has resulted in significant advances in the palliative care of patients with carcinoid syndrome 2.
- Hepatic vascular occlusion therapy, chemoembolization, and direct percutaneous ethanol injection are also considered for the treatment of liver metastases 5.