Carcinoid tumor treatment

Octreotide acetate is an endocrine and metabolic agent, whose actions mimic those of natural hormone somatostatin. It suppresses secretion of serotonin and gastroentero-pancreatic peptides (e.g., gastrin, insulin, glucagon, secretin, and motilin), and also suppresses the growth hormone. It is indicated in the symptomatic treatment of diarrhea associated with carcinoid tumors, treatment of profuse watery diarrhea associated with vasoactive intestinal peptide tumors (VIPoma), and to reduce blood levels of growth hormone and IGF-1 in acromegaly patients who have had inadequate response to or cannot be treated with resection, pituitary irradiation, and bromocriptine at maximally tolerated doses. 

Malignant carcinoid tumors, a symptom of carcinoid syndrome, presented a therapeutic challenge for many years until the introduction of interferon treatment in 1982 by Oberg and Eriksson [51]. They reported that 47 out of 111 patients (42%) treated with interferon- / (median dose of 6 mega-units (MU) of interferon-a, five... 

Ronnblom, L.E., Aim, G.V., and Oberg, K.E., Possible induction of systemic lupus erythematosus by interferon-alpha treatment in a patient with a malignant carcinoid tumor, J Intern Med., 227, 207,1990. 

Somatostatin has a very brief half-life in serum and is not useful clinically. An 8-amino acid analogue with 2 D-amino acids substituted for the naturally occurring L-amino acids is more stable, and monthly injections of a depot form of this analogue (octreotide, Sandostatin LAR) have several uses. Long-acting octreotide is used to treat acromegaly, as described earlier. It is also used to counteract unpleasant effects caused by overproduction of secreted bioactive substances produced by neuroendocrine tumors, including hyperinsulinemia from insulinomas and secretions from carcinoid tumors that cause severe diarrhea. Octreotide may also control severe diarrhea associated with AIDS that has not responded to other treatments. 

A patient with severe diarrhea as a result of a carcinoid tumor is a candidate for which of the following treatments ... 

Treatment of carcinoid and vasoactive intestinal peptide acromegaly (reduce blood levels of growth hormone), symptomatic treatment of metastatic carcinoid tumors, and profuse water diarrhea associated with intestinal tumors... 

Serotonin is an important neurotransmitter, a local hormone in the gut, a component of the platelet clotting process, and is thought to play a role in migraine headache. Serotonin is also one of the mediators of the signs and symptoms of carcinoid syndrome, an unusual manifestation of carcinoid tumor, a neoplasm of enterochromaffin cells. In patients whose tumor is not operable, a serotonin antagonist may constitute a useful treatment. 

The major clinical applications of cyproheptadine are in the treatment of the smooth muscle manifestations of carcinoid tumor and in cold-induced urticaria. The usual dosage in adults is 12-16 mg/d in three or four divided doses. It is of some value in serotonin syndrome, but because it is available only in tablet form, cyproheptadine must be crushed and administered by stomach tube in unconscious patients. 

A powerful new synthetic peptide that mimics the action of somatostatin, octreotide acetate (Sandostatin). is approved by the Food and Drug Administration (FDA) for (he treatment of certain rare forms of intestinal endocrine cancers, such as malignant carcinoid tumors and vasoactive intestinal peptide-secreting tumors (VIPomas). Octreotide acetate is indicated for long-term treatment of severe diarrhea associated with these carcinomas. 

FIGURE 36-2. Recommendations for treating chronic diarrhea. Follow these steps (1) Perform a careful history and physical examination. (2) The possible causes of chronic diarrhea are many. These can be classified into intestinal infections (bacterial or protozoal), inflammatory disease (Crohn s disease or ulcerative colitis), malabsorption (lactose intolerance), secretory hormonal tumor (intestinal carcinoid tumor or VIPoma), drug (antacid), factitious (laxative abuse), or motility disturbance (diabetes mellitus, irritable bowel syndrome, or hyperthyroidism). (3) If the diagnosis is uncertain, selected appropriate diagnostic studies should be ordered. (4) Once diagnosed, treatment is planned for the underlying cause with symptomatic antidiarrheal therapy. (5) If no specific cause can be identified, symptomatic therapy is prescribed. 

Octreotide, a synthetic octapeptide analog of endogenous somatostatin, is prescribed for the symptomatic treatment of carcinoid tumors and vasoactive intestinal peptide-secreting tumors (VIPomas). Metastatic intestinal carcinoid tumors secrete excessive... 

Octreotide (Sandostatin) injection is commercially available in the United States for subcutaneous or intravenous administration. A long-acting intramuscular formulation of octreotide (Sandostatin EAR) is also available for monthly administration. In addition to the treatment of acromegaly, octreotide has many other therapeutic uses, including the treatment of carcinoid tumors, vasoactive intestinal peptide tumors (VIPomas), gastrointestinal fistulas, variceal bleeding, diarrheal states, and irritable bowel syndrome. 

Streptozotocin is a naturally occurring nitrosourea useful for the treatment of advanced islet cell carcinomas and carcinoid tumors [107]. 

Carcinoid tumors—Symptomatic treatment of patients with metastatic carcinoid tumors, where... 

C. Clinical Uses Ketanserin has been studied as an antihypertensive drug. Ketanserin, cyproheptadine, and phenoxybenzamine may be of value (separately or in combination) in the treatment of carcinoid tumor, a neoplasm that secretes large amounts of serotonin (and peptides) and causes diarrhea, bronchoconstriction, and flushing. 

Useful irreversible antagonist for treatment of some carcinoid tumors... 

Although uptake of FDG is increased in most malignant tumor entities, there are some exceptions that require special attention in the context of a potential microsphere treatment, namely, hepatocellular carcinoma (HCC) and carcinoid tumors. 

Gupta S, Yao JC, Ahrar K et al (2003) Hepatic artery embolization and chemoembolization for treatment of patients with metastatic carcinoid tumors the M.D. Anderson experience. Cancer J 9 261-267... 

Kemeny N et al. (1999) Hepatic arterial infusion of chemotherapy after resection of hepatic metastases from colorectal cancer. N Engl J Med 341 2039-2048 Kim YH et al. (1999) Selective hepatic arterial chemoembolization for liver metastases in patients with carcinoid tumor or islet cell carcinoma. Cancer Invest 17 474-478 Konno T (1990) Targeting cancer chemotherapeutic agents by use of lipiodol contrast medium. Cancer 66 1897-1903 Konya A,Szendroi M (1992) Aneurysmal bone cysts treated by superselective embolization. Skeletal Radiol 21 167-172 Kramer SC et al. (1999) Interventional treatment of hemorrhages in advanced cervical carcinoma. Radiologe 39 795-798... 

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