Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0007095 (carcinoid)
 6,990 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Two patients with acromegaly secondary to ectopic GHRH secretion by metastatic carcinoid tumors were studied before and during therapy with the somatostatin analog octreotide (SMS 201-995). GH and GHRH secretory patterns were assessed during intermittent sc administration, continuous sc infusion (CSI), and continuous iv infusion of octreotide. Octreotide reduced serum GH and plasma GHRH levels in the two patients, although there was differential sensitivity of GH and GHRH. Intermittent sc therapy transiently lowered serum GH in both patients. A higher iv dose was required to reduce plasma GHRH by 50% than to reduce serum GH by 50% (2.0 vs. 0.05 micrograms/kg.h, respectively; patient 1). A similar pattern was found during CSI octreotide administration in the same patient. Chronic therapy with intermittent sc and CSI octreotide was assessed by serial 24-h profiles of GH and GHRH secretion in patient 2. Mean hourly serum GH levels decreased from a pretreatment level of 31.5 +/- 3.5 (+/- SE) to 9.5 +/- 1.5 micrograms/L during CSI therapy (1000 micrograms/day or 0.40 micrograms/kg.h). In contrast, plasma GHRH levels were less effectively suppressed. The mean serum GH levels and the variation in hourly GH values were reduced to a greater extent with CSI than with intermittent sc therapy. Serum insulin-like growth factor I also declined from 5.9 x 10(3) to 2.5 x 10(3) U/L during chronic CSI therapy (patient 2). CSI therapy with octreotide can be more effective than intermittent sc therapy in controlling GH excess in the rare syndrome of ectopic GHRH secretion, although serum GH may not decline to normal.
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PMID:Octreotide suppresses both growth hormone (GH) and GH-releasing hormone (GHRH) in acromegaly due to ectopic GHRH secretion. 249 33

A 59-yr-old woman with a disseminated carcinoid tumor was evaluated for acromegaly. She had previously undergone a hypophysectomy for acromegaly and an enlarged pituitary, with a reduction in her serum GH levels from 100 to 4 micrograms/L. Recurrence of acromegalic symptoms 2 yr later was accompanied by elevated serum GH (16 micrograms/L) and insulin-like growth factor I (IGF-I; 528 micrograms/L) and plasma GHRH levels (12 micrograms/L; normal, less than 30 ng/L). Computed tomographic scan did not reveal pituitary enlargement. Metastatic carcinoid tissue in bone removed at biopsy contained GHRH (100 pg/mg tissue). High performance liquid chromatography of plasma GHRH revealed predominantly GHRH-(3-40)-OH, a biologically inactive GHRH metabolite, along with mature GHRH forms, while carcinoid tissue contained both GHRH-(1-40)-OH and GHRH-(1-44)-NH2. Treatment with pergolide initially resulted in reduction in serum GH and IGF-I levels and amelioration of symptoms of acromegaly. However, after 14 months of pergolide therapy, serum GH levels increased despite administration of up to 1000 micrograms pergolide/day. Plasma GHRH levels remained elevated throughout the treatment period. Subsequent treatment with SMS 201-995, a long-acting somatostatin analog, for over 1 yr resulted in sustained reductions of ectopic GHRH secretion, GH hypersecretion, and IGF-I levels. Plasma GHRH levels correlated with simultaneously measured serum GH levels in response to acute SMS 201-995 administration. SMS 201-995 was an effective medical treatment for acromegaly caused by ectopic GHRH production in this patient.
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PMID:Medical management of acromegaly due to ectopic production of growth hormone-releasing hormone by a carcinoid tumor. 289 89

Diagnosis of ectopic acromegaly was made in a 21-year-old female patient who 3 years before had undergone a right pneumectomy for a disseminated bronchial carcinoid. Plasma growth hormone-releasing hormone (GHRH) concentrations were markedly elevated (6440 ng/l; normal value < 100 ng/l), as were serum GH (187 micrograms/l; normal < 5 micrograms/l) and plasma insulin-like growth factor I (IGF-I) levels (6.7 U/ml; normal < 2 U/ml). Retrospective immunohistochemical examination of the carcinoid tumor was positive for GHRH and the tumoral content of GHRH was 2130 ng/g wet weight. Subcutaneous treatment with octreotide was begun and first resulted in a profound inhibition of GH hypersecretion, normalization of plasma IGF-I and only partial reduction of GHRH concentrations. However, the initial dose of 3 x 100 micrograms had to be increased gradually to 4 x 750 micrograms because of a progressive deterioration of the hormonal control. After 15 months of intermittent therapy, octreotide was administered by continuous sc infusion. This treatment improved compliance, allowed the daily dose of octreotide to be reduced to 1500 micrograms and normalized serum GH levels. A near-normalization of the plasma IGF-I concentrations was also obtained, whereas the suppression of plasma GHRH concentrations remained incomplete. Despite favorable evolution of the endocrine parameters, intramedullar metastases were diagnosed and required radiation therapy. This observation emphasizes the superiority of continuous over intermittent administration of octreotide in the treatment of ectopic acromegaly. It also shows that the somatostatin analog acts more at the pituitary level to inhibit GH secretion than at the site of the neuroendocrine tumor.
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PMID:Subcutaneous octreotide treatment of a growth hormone-releasing hormone-secreting bronchial carcinoid: superiority of continuous versus intermittent administration to control hormonal secretion. 758 49

Ectopic GHRH-secreting tumors, such as carcinoid, rarely cause acromegaly. As protracted exposure to high levels of GH is associated with considerable morbidity and mortality, these patients require early and effective medical therapy to control hormonal hypersecretion. We employed a prolonged release somatostatin analog, lanreotide, to treat a patient with disseminated GHRH-producing carcinoid. Before treatment, the patient had a biochemical profile characteristic of active acromegaly. Plasma GHRH levels were markedly elevated (200-fold), and urinary 5-hydroxyindolacetic acid (5-HIAA) levels were increased (4-fold). Magnetic resonance imaging revealed a large asymmetrical pituitary mass consistent with somatotroph hyperplasia. Somatostatin receptor scintigraphy revealed multiple bony and soft tissue lesions as well as striking pituitary uptake. Lanreotide (30 mg) was administered weekly by im injection for 12 weeks. Rapid and sustained symptomatic clinical improvement with diminished soft tissue swelling and hyperhidrosis was observed. GHRH levels decreased by 70%; glucose-suppressed GH and insulin-like growth factor I levels were reduced by 90% and 75%, respectively, to near normal values; urinary 5-HIAA levels normalized; and the pituitary mass remained unchanged. Unfortunately, the patient died due to complications of osteogenic sarcoma. In conclusion, prolonged release lanreotide induced clinical and biochemical remission in this patient with diffusely metastatic GHRH-producing carcinoid. This long-acting drug thus offers an effective, well tolerated, and convenient medical therapy for control of hormonal hypersecretion induced by excess GHRH.
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PMID:Long-acting lanreotide induces clinical and biochemical remission of acromegaly caused by disseminated growth hormone-releasing hormone-secreting carcinoid. 1032 16