Malignant Carcinoid Syndrome Follow-up

Updated: Aug 03, 2021
  • Author: Luigi Santacroce, MD; Chief Editor: N Joseph Espat, MD, MS, FACS  more...
  • Print

Inpatient & Outpatient Medications

See the list below:

  • Always assess the color of the urine. Dark-brown or intensely yellow urine usually indicates dehydration, and  fluids must sometimes be given intravenously to keep up with the fluid loss from diarrhea.

  • Weigh the patient daily and replace the essential elements and vitamins, either by diet or by commercial supplements.

  • Other clinical problems associated with carcinoid syndrome, such as tachycardia and asthmalike attacks, should be managed by a cardiologist and pulmonologist.

  • Severe flushes may be treated with clonidine.

  • Patients need to avoid conditions or substances that cause flushing (eg, stress, alcohol, epinephrine, epinephrinelike drugs).

The safety of antidepressants—especially selective serotonin reuptake inhibitors (SSRIs)—in patients with neuroendocrine tumors (NETs) has been questioned, since serotonin secretion by NETs contributes to carcinoid syndrome. However, Isenberg-Grzeda et al reviewed antidepressant treatment in 92 patients with NETs, including 16 with carcinoid, and found that none of the patients developed carcinoid syndrome or carcinoid crisis during antidepressant use. [66]



Patients must avoid any physical and emotional stress and any food or drug that may trigger a crisis. For example, monamine oxidase inhibitors should be avoided because they can exacerbate the syndrome by inhibiting serotonin degradation.



Complications may include the following [67] :

  • Hypotension related to massive vasodilation can increase the risk of falls and subsequent injuries.

  • Increased platelet aggregation causes a high risk for strokes, deep venous thromboses, and similar disorders.

  • Gastrointestinal bleeding is very rare. Bowel obstruction from tumor mass or, most frequently, from mesenteric adhesions is also very rare.

  • Right-sided heart failure is more frequent.

  • Analysis of catecholamines and associated metabolites shows consistent elevation of dopamine, norepinephrine, and epinephrine metabolites in more than 30% of midgut carcinoids. This explains some adverse effects (eg, arrhythmias, perioperative carcinoid crisis) in patients in whom octreotide premedication is indicated.

  • Usually, urinary levels of histamine metabolites are less elevated, but increased histamine production can cause specific symptoms (eg, angioedema), which should be treated specifically.

  • Acute renal failure after liver chemoembolization of carcinoid metastases is an infrequent but well-known complication.

  • Metastasis

Risk of metastasis correlates with size of primary tumor, as follows:

  • Tumors ≤1 cm metastasize in only 2% of cases
  • Tumors 1-2 cm metastasize in 50% of cases
  • Tumors ≥2 cm metastasize in 85% of cases


The prognosis for patients with malignant carcinoid syndrome is relatively good compared with the prognosis for patients with other malignancies, but the prognosis for any treated patient with progressing, recurring, or relapsing disease is poor. The median survival rate after 5 years is 30-67%. Survival for 8.5 years and 23 years has been reported.

In patients with malignant carcinoid syndrome who are cured with surgery, follow-up care does not need to be intensive. For patients with advanced disease, follow-up care should be scheduled on a regular basis. The frequency of follow-up care depends on the general condition of patients and their disease. In each follow-up session, blood tests, x-ray films, and other studies may need to be performed complementary to patient examination.

For many patients, the treatment options for carcinoid syndromes have prolonged life, but it is very important to understand the patient’s perception of symptoms and the influence of treatment, which may affect quality of life as well as disease progression. [68, 69]

The incidence of metastasis is estimated at 1-2 cases per 100,000 affected people, and the best treatment remains controversial. Lymph nodes and liver are the most common sites of metastasis, and bone and lung are less commonly affected. Involvement of distant sites (eg, ovary, orbit) is very rare. Most patients with metastases are asymptomatic and have an indolent course. If patients are left untreated, survival at 5 years is 30%.


Patient Education

See the list below: