Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “ADENOMA”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 127 records · Page 7Linked to original sources
PubMed1992

Bile duct adenomas with endocrine component. Immunohistochemical study and comparison with conventional bile duct adenomas.

Bile duct adenomas are small nodules that are usually found incidentally on the liver surface at abdominal surgery or autopsy. We recently analyzed two such lesions that, in addition to the typical small caliber ducts, contained periductular nests and clusters of uniform round cells, suggestive of endocrine cell proliferation. Follow-up of these patients did not show endocrine tumors elsewhere. The lesions were studied by immunohistochemistry (avidin-biotin-peroxidase technique) and compared with conventional bile duct adenomas (seven cases). The results showed these cells to decorate with several endocrine markers, namely, neuron-specific enolase, chromogranin, synaptophysin, and Leu-7. Endocrine markers were not seen in the cells of conventional bile duct adenomas. Epithelial markers, that is, cytokeratin (CAM 5.2 antibody) and epithelial membrane antigen, were expressed by the cells composing both conventional bile duct adenomas and those with endocrine-like cells, although with less intensity in the endocrine cell clusters. We suggest that some bile duct adenomas contain endocrine cell proliferations that morphologically may resemble a small carcinoid tumor or the so-called pulmonary tumorlet. Neurosecretory granules have previously been identified in some cholangiocarcinomas and in bile duct proliferation associated with cholestasis. The endocrine clusters in biliary adenomas may constitute a diagnostic pitfall and must be separated from metastases of carcinoids or islet cell tumors.

Adenoma↗
PubMed2003

Crooke's cell adenoma of the pituitary: an aggressive variant of corticotroph adenoma.

Cushing's disease is caused by functional corticotroph adenomas of the pituitary, mostly noninvasive microadenomas. Classic Crooke's cells are nonneoplastic corticotrophs with cytoplasmic accumulation of cytokeratin filaments in response to glucocorticoid excess. Corticotroph adenomas exhibiting Crooke's change are rare and incompletely understood. We intend to define more clearly the clinicopathological features of Crooke's cell adenomas (CCA). Thirty-six CCAs were retrieved from the files of Mayo Clinic and from our (B.W.S., K.K.) consultation files. The number of informative cases varied for different criteria. Clinical follow-up was obtained in 31 cases. The 27 females and 9 males were 18 to 81 years of age (mean 46 years). At presentation, Cushing's disease was evident in 22/34 (65%); 81% were macroadenomas and 72% were invasive. All were initially treated by transsphenoidal resection. Twenty-five patients were followed for more than 1 year (mean 6.7 years). Of these, 15 (60%) developed recurrent tumor, and 6 (24%) had multiple recurrences. Lastly, 3 of these 25 patients (12%) died of tumor: 1 after multiple local recurrences and 2 from pituitary carcinoma. Compared with typical corticotroph adenomas, CCAs are aggressive. Most are functional adenomas occurring in middle-aged women and are invasive macroadenomas prone to recurrence. Morbidity and mortality rates are substantial. CCAs represent a distinct entity that should be separated from corticotroph adenomas without Crooke's hyaline change.

Adenoma↗
PubMedDate not supplied

A multicenter study of colorectal adenomas. Rationale, objectives, methods and characteristics of the study cohort. The Multicentric Study of Colorectal Adenomas (SMAC) Workgroup.

BACKGROUND AND AIMS: The Multicenter Study of Colorectal Adenomas (SMAC) is a retrospective-prospective cohort study involving four Gastrointestinal Endoscopy Units in Italy. The main aim of the study is to evaluate the relationship between clinical and pathologic information at index colonoscopy and subsequent incidence of adenoma and colorectal carcinoma. We report the rationale, objectives and methods of the study, including patient characteristics at initial presentation. METHODS: All patients were consecutively identified from the endoscopy registries of the four Centres from January 1, 1985 to December 31, 1992. Inclusion criteria were: age 18-69 years, endoscopy performed with adequate toilette at least up to the rectosigmoid junction, and removal of all detectable polyps. Exclusion criteria were: familial adenomatous polyposis, inflammatory bowel diseases, adenocarcinoma in adenoma with infiltrated margins, previous invasive cancer at any site, colon resection and geographic inaccessibility. RESULTS: Out of 20,071 patients who underwent endoscopy at the four Centres, 11,959 fulfilled the eligibility criteria (5,892 males and 6,067 females, mean age = 51.1 +/- 11.6 years). The main reasons for exclusion were age (n = 4,020) and previous or present colorectal cancer (n = 2,389). Symptoms were the most common reason for referral (72.3%), while post-polypectomy follow-up and positive fecal occult blood accounted for most of the remaining cases. A pancolonoscopy was performed in 3,088 patients (25.8%), while a left-sided endoscopy was performed in 7,887 (66%). A total number of 4,810 polyps were removed from 2,699 patients (2,994 adenomas, 1,580 hyperplastic polyps and 236 polyps lost after resection). A significant association (p < 0.001) between age and the endoscopic findings was observed. The subjects without polyps (n = 9,198) had the lowest age (mean = 49.9; 95%CL = 49.6-50.1) followed by the patients with hyperplastic polyps (n = 661; mean age = 52.3; 95%CL = 51.5-53.1), and the patients with adenomas (n = 1,732; mean age = 56.2; 95%CL = 55.8-56.6), and the patients with hyperplastic polyps and adenomas (n = 306; mean age = 57.2; 95%CL = 56.3-58.2). Polyps were diagnosed more frequently in males than in females (28.6% versus 17.0%; p < 0.0001). CONCLUSION: This study provides some insights in the natural history of colorectal cancer and stresses the need to develop adequate strategies in the follow-up of subjects after either positive or negative colonoscopy.

Adenoma↗
PubMed1997

A case of nonfunctioning pituitary adenoma resembling so-called silent corticotroph adenoma.

It has been indicated that some subsets of clinically nonfunctioning pituitary adenoma exhibit immunohistochemical and ultrastructural features of somatotroph or corticotroph cells, which are described as silent somatotroph and corticotroph adenomas, respectively. We here describe a 70-year-old woman with nonfunctioning pituitary adenoma presenting with visual disturbance. None of the pituitary hormones show abnormal finding. Magnetic resonance imaging study revealed a pituitary tumor which developed inferiorly into the sphenoidal sinus. Tumor resection was performed by a transsphenoidal approach, and resulted in a partial resection of the tumor. The specimen indicated chromophobic adenoma. Immunohistochemical examination revealed a characteristic distribution pattern of cytokeratin staining for ACTH cell adenoma, although immunostaining for ACTH was only weakly positive. After the operation, only ACTH secretion was impaired, requiring replacement therapy with glucocorticoid. Bromocriptine was administered in order to prevent the recurrence of the tumor. It remains to be elucidated whether the present case could be classified as silent corticotroph adenoma, which was originally indicated to have aggressive characteristics, i.e., progressive visual defect, high incidence of infarction and frequent recurrence.

Adenoma, Chromophobe↗
PubMed1993

Pit-1/GHF-1 expression in pituitary adenomas: further analogy between human adenomas and rat SMtTW tumours.

Adenomas can develop from each cell type of the anterior pituitary. In the normal pituitary, three of these cells types, the GH-, prolactin- and TSH-secreting cells, express the transcription factor Pit-1/GHF-1 which is responsible for prolactin and GH (and probably TSH) cell commitment, differentiation, probably proliferation and gene expression. We have analysed the expression of Pit-1/GHF-1 in a panel of human pituitary adenomas. All GH-, prolactin- and TSH-expressing adenomas studied expressed the Pit-1/GHF-1 factor, as demonstrated by in-situ hybridization and immunocytochemistry. The expression was higher in adenomas than in normal human pituitary. In contrast, ACTH- and LH-FSH-secreting and non-secreting adenomas were negative. Seven transplants of the spontaneous rat prolactinoma SMtTW were also investigated and all were found to be positive. This further stresses the analogy between these tumours and human prolactinomas. Taken together, the data confirm that Pit-1/GHF-1 expression is restricted to GH-, prolactin- and TSH-expressing cells, and the increased expression in adenomas is compatible with a role of Pit-1/GHF-1 in cell proliferation.

Adenoma↗
PubMed1988

Colorectal adenomas and food. A prospective study of change in volume and total mass of adenomas in man.

In an endoscopic population screening study for detection of colorectal polyps the diet was registered before ascertaining whether polyps were present. Polyps less than 5 mm in diameter were followed up for 2 years before removal and histologic diagnosis. The relative risk of an increase both in the volume of registered adenomas (excluding new adenomas) and in the total mass of adenomas (including new adenomas) showed a trend towards an inverse relationship with intake of dietary fiber, non-fiber carbohydrate, and cruciferous vegetables, reaching the significance level only for intake of dietary fiber for increase of adenoma volume in men. A trend towards a positive relationship between growth and total fat intake was more inconsistent, although the significance level was reached for the relative risk of increase in adenoma mass for men. These prospective observations with regard to polyp-bearing individuals agree with previous incidence and prevalence data that have indicated a relationship between dietary habits and colorectal carcinogenesis.

Adenoma↗
PubMed1990

[A rare case of pleomorphic adenoma of lateral wall of nasal cavity--with special reference of statistical observation of pleomorphic adenoma of nasal cavity in Japan].

Pleomorphic adenoma, which is also called mixed tumor is considered to occur favorably in major salivary glands such as parotid and submandibular glands, and rarely in the nasal cavity, pharynx, larynx, trachea, and lacrimal gland. We reported here a rare case of pleomorphic adenoma (2.9 X 2.2 X 1.7 cm3) developed from the lateral wall of right nasal cavity in a 43-year-old woman. Statistical observation of pleomorphic adenoma of the nasal cavity in Japan was made and comparative study was also made between such adenoma and that in the parotid gland. In Japan, 41 cases of pleomorphic adenoma originated in the nasal cavity have been reported so far including ours. These cases had age of onset of 16-74 years, averaging 44.6 years. Sex ratio showed female predominance. No significant difference was noted in affected sides sites. Chief complaints were represented mostly by nasal obstruction (29 cases; 71%) and nasal bleeding (23 cases; 56%). Tumors were surgically extirpated in all cases. One recurrent case (2.4%) was reported and another malignant case (2.4%) was also reported. 4 cases (9.8%) were originated in the lateral wall of nasal cavity and all of the other cases were in the nasal septum. In comparison with pleomorphic adenoma developed in parotid gland in Japan, sex ratio was 1:1.8 compared with 1:2.1 for parotid gland with almost similar tendency. Age of onset averaged 44.6 compare with 32.8 years for parotid gland, with a little advance in age.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenoma, Pleomorphic↗
PubMed2006

Proliferating cell nuclear antigen (PCNA) expression in pituitary adenomas: relationship to the endocrine phenotype of adenoma.

The expression of proliferating cell nuclear antigen (PCNA) correlates to cell proliferation and for this reason it is commonly considered as one of proliferation markers. Since proliferation rate is an important factor determining the tumor aggressiveness, the evaluation of PCNA index (the percentage of PCNA-immunopositive nuclei in the investigated tumor sample) is suggested as useful in predicting pituitary adenoma outcome. Seventy three unselected, surgically removed pituitary adenomas were immunostained with antibodies against the pituitary hormones or their subunits and against the proliferating cell nuclear antigen (PCNA). The highest PCNA index was found in ACTH-immunopositive tumors without the manifestation of the Cushing's disease ("silent" corticotropinomas). This value was significantly different in comparison to other adenoma subtypes including corticotropinomas manifesting themselves by Cushing's disease. The lowest PCNA index was noticed in monohormonal GH-secreting tumors. The adenomas which express more than one hormone (plurihormonal adenomas) seem to have a higher PCNA indices than monohormonal ones; the difference was significant in the case of mono- and plurihormonal prolactinomas. The recurrent tumors presented a higher mean PCNA index as compared to the primary tumors, although the difference was significant only in the case of prolactinomas. These findings suggest that the proliferative potential of pituitary adenomas is related to the tumor recurrence and hormone expression.

Adenoma↗
PubMed2005

Basal cell adenoma and lymphoepithelial cyst as recurrent tumors of pleomorphic adenoma of the parotid gland.

Basal cell adenoma of the parotid gland is a rare benign tumor. Lymphoepithelial cyst of the parotid gland is also a rare benign tumor-like lesion. We report an elderly woman, who previously underwent a removal of pleomorphic adenoma, with multiple masses in the left parotid gland. Physical, MR and intra-operative examination suggested the masses as multiple recurrences of the previous pleomorphic adenoma. A total parotidectomy with facial nerve preservation was performed. The histological examination revealed that the masses were two basal cell adenomas and one lymphoepithelial cyst. These rare tumors should be considered in the differential diagnosis of recurrent masses after a removal of pleomorphic adenoma of the parotid gland.

Adenoma↗
PubMed2001

Colorectal adenomas and diet: a case-control study. Colorectal Adenoma Study Group.

It has been postulated that high intakes of animal fat and protein and low intakes of fiber, calcium, and antioxidants increase the risk of colorectal cancer. Whether specific types of protein such as that from red meat are important, and whether vegetables might be key protective factors will also be considered in this study. Dietary intake over the past year was studied according to the diet history method by means of a case-control study in 184 cases and matched controls. After adjustment for energy, relative weight, and social class, no associations were found for fat or protein in comparison with either control group. Unexpectedly, carbohydrate intake was inversely related with adenoma risk, the RR being 0.29 (0.10-0.81) for quintile 5 versus 1 in comparison with hospital controls. None of the antioxidants showed a significant protective effect except beta-carotene intake in comparison with hospital controls, the RR being 0.24 (0.11-0.50) for the highest versus the lowest quintile. There was, however, a statistically significant positive association between adenomas and meat consumption with the RR for the highest versus the lowest quintile. There was, however, a statistically significant positive association between adenomas and meat consumption with the RR for the highest versus the lowest quintile of intake being 3.6 (1.7-7.5) in comparison with hospital controls and 4.4 (1.6-12.1) in comparison with population controls. Our data support the protective role for carbohydrate intake and of beta-carotene intake in the etiology of colorectal adenomas and show a strong increased risk for developing adenomas in those with high meat intake.

Adenoma↗
PubMed1991

Univariate and multivariate analyses of the relationship between adenocarcinoma and solitary and multiple adenomas in colorectal adenoma patients.

In 584 consecutive patients with no previous history of cancer or polypectomy, 769 adenomas were excised endoscopically and classified retrospectively according to the following parameters: macroscopic growth pattern, size, histological type, grade of dysplasia, anatomical site, presence of adenocarcinoma (ADK), number of adenomas and sex and age of the patient. A multivariate logistic analysis confirmed that size and histological type are the 2 most important predictors of ADK, both in solitary and in multiple adenomas. Adenomas located in the sigmoid portion and in the rectum have an increased probability of ADK, independent of size and histology. Multiple polyps, when compared to solitary polyps, were more frequent in males (p less than 0.01) and were more often larger than 2 cm. Significant similarities in histology, morphology and degree of dysplasia were observed among multiple adenomas from the same patient.

Adenocarcinoma↗
PubMed2004

Prolactin-producing pituitary adenoma with incomplete neuronal transformation: an intermediate adenoma-neuronal tumor.

We present a unique case of a prolactin (PRL)-producing pituitary adenoma showing incomplete neuronal differentiation without ganglion cells. A 27-year-old man presented with nausea, headaches, and instability over the last 2 months. Clinical examination revealed obesity with no other endocrinological signs. His serum PRL levels were slightly elevated (38 ng/ml), whereas concentrations of the other adenohypophysial hormones were within normal range. Histology revealed an unusual pituitary adenoma containing many hypocellular areas with fibrillar appearance. The sizable tumor cells were polyhedral or elongated harboring an ovoid, vesicular nucleus with prominent nucleolus, lacking, however, the typical features of ganglion cells. By immunohistochemistry, many adenoma cells were positive for PRL. Immunostain for neurofilament protein revealed variable amounts of fibrils dispersed throughout the stroma, mostly in the hypocellular areas. In addition, neurofilament protein and chromogranin were strongly reactive in approximately 15% of the tumor cell population, whereas reactivity for synaptophysin was uniform throughout the tumor. These findings led to the conclusion that part of the tumor-cell population expressed a hybrid immunoprofile of adenoma-neuronal cell. Our case is the first PRL-producing pituitary adenoma showing incomplete neuronal differentiation lacking mature ganglion cells.

Adenoma↗
PubMed2001

Morphometric analysis, at electron microscope level, combined with hormone assay of nonfunctioning adrenocortical adenomas: comparison with aldosterone-producing adenomas.

We performed electron microscopic studies of eight nonfunctioning adrenocortical adenomas (NFA) and nine aldosterone-producing adenomas (APA) obtained from surgical specimens. A comparison of these two types of adenomas was conducted by morphometric analysis of random electron micrographs. The organelles measured included mitochondria (M), smooth-surfaced endoplasmic reticulum (SER), rough-surfaced endoplasmic reticulum (RER), lipid vacuoles (LV), and lysosomes (Ly). The content of steroid hormones, including 17-alpha hydroxyprogesterone (17-OHP), aldosterone (Ald), and other steroid hormones, was measured in adenoma tissue from six NFA and eight APA. The percentages of the areas of the organelles M, SER, and RER per total cell area in the NFA were significantly lower than those in the APA. The average content of Ald in adenoma tissues in APA was markedly higher than that in the NFA, while the mean content of 17-OHP in the NFA was significantly higher than that in APA. In conclusion, NFA are morphometrically characterized by a reduction in organelles such as M, SER, and RER, compared with findings in APA. From the quantitative analysis of steroid hormones, it was suggested that NFA produce more precursor substances with less hormone activity than APA and that steroidgenesis in NFA is shifted to a glucocorticoid pathway, as indicated by the elevated 17-OHP concentration.

Adenoma↗
PubMed1993

Tubulo-papillary adenoma (so-called nephrogenic adenoma) arising in the renal pelvis. Report of a case with a critical consideration of histogenesis and terminology.

This is the first detailed clinical and histopathologic report of a tubulo-papillary adenoma (so-called nephrogenic adenoma) arising in the renal pelvis of a 35-year-old woman. The tumor showed a polypoid exophytic growth and consisted of closely packed tubular formations lined by cuboidal to low columnar cells with an admixture of delicate papillary structures. Its benign nature was indicated by the lack of cellular atypias, the extremely low proliferative activity and the absence of invasiveness. We favor the metaplastic theory of origin rather than an embryologic (dysontogenetic) derivation from mesonephric remnants as the underlying histogenetic principle. The descriptive term "tubulo-papillary adenoma" seems more appropriate than the designation "nephrogenic adenoma". True tumors of this type should clearly be distinguished from metaplastic tubular, papillary or tubulo-papillary cuboidal hyperplasias of the urothelium (so-called nephrogenic metaplasia) which are considered preneoplastic and assumed to be immediate precursors of adenomas of the lower urinary tract.

Adenoma↗
PubMed2003

Neural adhesion molecule (N-CAM) in pleomorphic adenoma and carcinoma ex-pleomorphic adenoma.

BACKGROUND: The neural cell adhesion molecule (N-CAM) has been implicated in the behaviour of the adenoid cystic carcinoma. In vitro, it was demonstrated that N-CAM inhibits cell invasion. The aim of this study was to search for N-CAM in the most common salivary gland tumour that has a malignant counterpart. METHODS: We investigated the presence of N-CAM in pleomorphic adenoma and its malignant counterpart, the carcinoma ex-pleomorphic adenoma, using the immunohistochemistry technique. RESULTS: Neural cell adhesion molecule was expressed in all cases of pleomorphic adenoma, strongly labelling the luminal cells of the double-layered ductform structures. This expression was weaker in neoplastic myoepithelial cells and progressively diminished at a distance from the luminal cells. In carcinoma, ex-pleomorphic adenoma N-CAM was either totally absent or faintly present at the apical pole of the few luminal cells. CONCLUSIONS: As a result of the peculiar distribution of N-CAM in pleomorphic adenoma, we speculated that N-CAM behaves as a tumour-suppressor molecule, which is expressed in the benign neoplasm and which is down-regulated after malignancy, when the tumour assumes an invasive behaviour.

Adenocarcinoma↗
PubMed2002

The role of adenoma for colorectal cancer development: differences in the distribution of adenoma with low-grade dysplasia, high-grade dysplasia, and cancer that invades the submucosa.

BACKGROUND: The purpose of this study was to elucidate the role of adenoma in the early stage of colorectal cancer development, we focused on the clinicopathologic relationship between adenoma with low-grade dysplasia (ALGD), adenoma with high-grade dysplasia (AHGD), and cancer that invades the submucosa in the colorectum. METHODS: We clinicopathologically examined a total of 553 adenomas and 58 cancers that invaded the submucosa. The tissues were excised from 479 patients who underwent total colonoscopy. RESULTS: The percentage of ALGD was 79.9% in the proximal colon, 70.5% in the distal colon, and 48.3% in the rectum, respectively. The percentages of AHGD and cancer were 14.5% and 5.6% in the proximal colon, 21.3% and 8.2% in the distal colon, and 35.4% and 16.3% in the rectum, respectively. In contrast with the distribution of ALGD, the distribution of both AHGD and cancer shifted from the proximal to the distal site, with a statistical significance (P <.01). When the distribution of adenoma was compared according to tumor size, both large- and small-sized AHGD showed a similar cancer distribution, however, both large- and small-sized ALGD showed different distributions. CONCLUSION: An important role of AHGD for cancer development in the colorectum may relate to the similar distribution between AHGD and cancer; however, the different distributions observed between ALGD, AHGD, and cancer suggested that ALGD has only a slight association with the development of cancer.

Adenoma↗
PubMed1998

Overexpression of p53 protein correlates with a high risk of malignant transformation of adenomas in patients with multiple colorectal adenomas.

To assess the correlation of p53 oncoprotein expression with the high risk of developing carcinomas in patients with multiple colorectal adenomas, 25 cases with histologic carcinoma in adenoma (CIA) were examined by immunohistochemistry using a monoclonal antibody specific to human p53 protein (wild and mutant). The 25 cases were classified into multiple and single groups. The former contained 13 cases with synchronous multiple colorectal adenomas (one to six adenomas) and adenocarcinoma. The latter included 12 cases with single CIA only. This study revealed an overall incidence of 57.14% of p53 overexpression in carcinomatous lesions and 31.9% in adenomatous lesions, which was statistically significant (P < 0.05). The carcinomatous lesions showed a diffuse staining pattern, whereas the adenomatous lesions showed a focal pattern. A significant finding was that the incidence of p53 overexpression was significantly higher in multiple groups (81.25%) than in single groups (31.43%) in the carcinomatous (P < 0.01) rather than in the adenomatous (P < 0.05) lesions. There were no correlations between p53 overexpression and proliferation activity or carcinoembryonic antigen expression. The results indicate that p53 abnormality may be an important genetic factor responsible for the high risk of developing carcinomas in patients with multiple adenomas.

Adenoma↗
PubMed1990

Endocrine and immunohistochemical studies on thyrotropin (TSH)-secreting pituitary adenomas: responses of TSH, alpha-subunit, and growth hormone to hypothalamic releasing hormones and their distribution in adenoma cells.

Endocrine and immunohistochemical studies were performed in two cases of TSH-secreting pituitary adenomas. The patients had elevated serum TSH and alpha-subunit concentrations despite high serum thyroid hormone levels. In addition, one patient (no. 1) had elevated serum GH levels with clinical evidence of acromegaly. GH-releasing hormone infusion increased serum levels of TSH, alpha-subunit and GH in the two patients. TRH injection increased serum TSH levels in both patients and, concomitantly, serum alpha-subunit and GH levels in patient 1. Basal TSH levels and their responses to TRH changed reciprocally to changes in serum thyroid hormone levels, although TRH-induced GH release did not. The administration of GnRH also increased serum TSH, alpha-subunit, and GH levels in patient 1. In accordance with these in vivo results, pituitary adenoma cells in culture obtained from patient 1 responded to GH-releasing hormone, TRH, or GnRH to secrete TSH, alpha-subunit, and GH. Incubation of cells with dexamethasone resulted in inhibition of TSH and stimulation of GH secretion without a significant change in alpha-subunit secretion. On the basis of light microscopic and electron microscopic double gold immunohistochemistry, the tumor from patient 1 was a bimorphous adenoma composed of two separate cell types: cells with TSH beta-subunit (TSH beta) and alpha-subunit, and those with GH and alpha-subunit. The remainder consisted mainly of cells with TSH beta and alpha-subunit. The coproduction of the unusual combination of two hormones such as GH and alpha-subunit in a single-type of adenoma cell and the coexistence of thyrotrophs and somatotrophs in one pituitary adenoma along with the aberrant responses of TSH beta, alpha-subunit, and GH to multiple hypothalamic hormones suggest the dedifferentiation of pituitary cells to multipotential progenitor cells by neoplastic transformation.

Adenoma↗