Monitoring
Monitoring patients with carcinoid tumors and pancreatic neuroendocrine tumors (pNETs) is recommended in order to assess whether there is progression of disease.1,2 Optimal monitoring of patients requires a multidisciplinary approach with nurses, primary care practitioners, gastroenterologists, oncologists (medical, surgical, and radiation), radiologists, endocrinologists, nuclear medicine physicians, molecular geneticists, clinical immunologists, pathologists, and surgeons involved in the follow-up process.1,3
The National Comprehensive Cancer Network (NCCN) recommends that all patients with carcinoid tumors be re-evaluated 3 to 12 months postresection, and every 6 to 12 months thereafter with history and physical examination and imaging as clinically indicated.1 It is recommended that patients with midgut carcinoid tumors be reassessed once between 3 and 6 months after complete resection.2 Subsequently, patients with midgut carcinoid tumors should be assessed every 6 to 12 months for at least 7 years.2
General surveillance for carcinoid tumors and pNETs should include a history and physical examination, measurement of urinary 5-hydroxyindoleacetic acid (5-HIAA) and serum chromogranin A (CgA), abdominal/pelvic triple-phase contrast-enhanced computed tomography (CT), magnetic resonance imaging (MRI), and/or SRS scans and measurement of biochemical markers.2 Surveillance may vary according to treatment setting (Table 8).
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Table 8. Surveillance by Treatment Setting: Postresection, Recurrent, Unresectable, Localized and Metastatic Disease1 |
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|---|---|---|---|---|
Postresection |
Recurrent disease |
Unresectable disease |
Localized disease |
Metastatic disease |
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Prognosis
Prognostic indicators allow physicians to monitor disease progression.4 Table 9 lists both positive and negative prognostic indicators (Table 9).
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Table 9. Prognostic Indicators4-6 |
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|---|---|---|---|
Positive Indicators |
Negative Indicators |
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Age <50 years5 |
Hepatic metastases5 |
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Female gender5 |
Atypical histological features5 |
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Low grade6 |
Presence of carcinoid syndrome5 |
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Tumor size <3 cm5 |
Distant metastases6 |
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Well differentiated6 |
Presence of second malignancy5 |
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Low levels of CgA5 |
High levels of pancreastatin4 |
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Low levels of neurokinin A4 |
Depth of invasion5 |
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The development or presence of a second malignancy such as an adenocarcinoma is associated with a worse prognosis, as is the occurence of carcinoid syndrome.5 High levels of pancreastatin confer a poor prognosis due to active progressive liver disease.4
For patients with NETs and distant metastases, the 5-year survival rates are 35% for well differentiated/moderately differentiated and 4% for poorly differentiated/anaplastic carcinoid tumors.6
It is important to note here that patients presenting with relatively small primary tumors can have metastatic potential.7
Survival can also be affected by the presence of symptomatic carcinoid heart disease (4.4 year median survival), skeletal metastases (3-year median survival from diagnosis of bone lesions),8 and high CgA levels (5-year median survival: 22% compared with 63% for low CgA levels).9 Low levels of neurokinin A increase survival in patients with midgut carcinoid tumors.4
