ABSTRACT
Ectopic acromegaly is a rare condition caused by extrapituitary central or peripheral neuroendocrine tumours (NET) that hypersecrete GH or, more commonly, GHRH. It affects less than 1% of acromegaly patients and a misdiagnosis of classic acromegaly can lead to an inappropriate pituitary surgery. Four types of ectopic acromegaly have been described: 1) Central ectopic GH-secretion: Careful cross-sectional imaging is required to exclude ectopic pituitary adenomas. 2) Peripheral GH secretion: Extremely rare. 3) Central ectopic GHRH secretion: Sellar gangliocytomas immunohistochemically positive for GHRH are found after pituitary surgery. 4) Peripheral GHRH secretion: The most common type of ectopic acromegaly is due to peripheral GHRH-secreting NETs. Tumours are large and usually located in the lungs or pancreas. Pituitary hyperplasia resulting from chronic GHRH stimulation is difficult to detect or can be misinterpreted as pituitary adenoma in the MRI. Measurement of serum GHRH levels is a specific and useful diagnostic tool. Surgery of GHRH-secreting NETs is often curative.
Subject(s)
Acromegaly , Growth Hormone-Releasing Hormone , Humans , Acromegaly/diagnosis , Acromegaly/etiology , Acromegaly/blood , Growth Hormone-Releasing Hormone/metabolism , Neuroendocrine Tumors/diagnosis , Neuroendocrine Tumors/metabolism , Neuroendocrine Tumors/complications , Human Growth Hormone/blood , Human Growth Hormone/metabolism , Pituitary Neoplasms/diagnosis , Pituitary Neoplasms/surgery , Pituitary Neoplasms/complications , Pituitary Neoplasms/metabolismABSTRACT
The impact of interstitial inflammatory cells, such as mast cells, and angiogenesis on the prognosis of cancer patients has been reported in many solid tumors, although there is disagreement about their role. We undertook a retrospective study with tissue samples from 65 patients with stage I and II non-small cell lung cancer to assess the clinical pathologic role and prognostic significance of mast cells. Mast cell phenotypes were identified by immunohistochemistry for tryptase and chymase. In addition, we identified microvessels using the endothelial marker CD34. Mast cell and microvessel density was quantified by assessing immunopositive cells in the intratumoral and peritumoral zones of tumor specimens. Both mast cell and microvessel density was higher in the peritumoral zone than the intratumoral zone (P Subject(s)
Carcinoma, Non-Small-Cell Lung/pathology
, Lung Neoplasms/pathology
, Lung/blood supply
, Mast Cells/pathology
, Microvessels/pathology
, Neovascularization, Pathologic/pathology
, Age Factors
, Aged
, Aged, 80 and over
, Carcinoma, Non-Small-Cell Lung/mortality
, Chi-Square Distribution
, Female
, Humans
, Immunohistochemistry
, Lung/pathology
, Lung Neoplasms/mortality
, Male
, Middle Aged
, Neoplasm Staging
, Prognosis
, Proportional Hazards Models
, Retrospective Studies
, Statistics, Nonparametric
