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Query: UMLS:C0001430 (adenoma)
 21,222 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Histological, immunohistochemical, and flow cytometric characteristics of three unusual parotid gland tumors are described. The patients were adult white men with carcinoma ex pleomorphic adenoma, true malignant mixed tumor, and primary parotid gland chondrosarcoma. The carcinoma ex pleomorphic adenoma showed evidence of simultaneous epithelial, myoepithelial, and mesenchymal differentiation by immunohistochemistry. The true malignant mixed tumor exhibited variable positivity for two keratins, vimentin, proliferating cell nuclear antigen, Ki67, and p53. The chondrosarcoma initially stained for vimentin, S100, muscle-specific actin, proliferating cell nuclear antigen, and Ki67, but it lost actin expression in its first recurrence, accompanied by more extensive Ki67 staining. DNA ploidy varied from diploid to aneuploid with intratumoral variation in the carcinosarcoma. S-phase fractions ranged from 2.43% to 13.9%. The findings underscore the diversity of tumors that may be pathogenetically related to, and at times derived from, pleomorphic adenoma.
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PMID:Unusual mesenchymal and mixed tumors of the salivary gland. An immunohistochemical and flow cytometric analysis of three cases. 780 57

Forty-nine follicular adenomas and 11 follicular carcinomas of the thyroid were investigated by immunohistochemistry for the expression of p53 protein and proliferating cell nuclear antigen (PCNA). The DNA ploidy and the S-phase fraction (SPF) of the neoplasms were analysed by flow cytometry. Twelve adenomas (24 per cent) and six carcinomas (55 per cent) were DNA non-diploid (P = 0.07). The carcinomas had a higher proliferation rate than the adenomas when assessed either by SPF size (median 9.9 per cent vs. 2.9 per cent, P = 0.0003) or by PCNA staining intensity (P < 0.0001). Some scattered nuclei in two (4 per cent) adenomas and in three (27 per cent) carcinomas stained positively for p53 (P = 0.04). The two adenomas with positive staining for p53 were subserially sectioned, but no signs of invasion were found; both patients are alive and well 6 and 7 years after surgery. One of the two adenomas showing positive p53 nuclear staining was DNA aneuploid, and both were positive in PCNA staining, but their SPFs were low (2.1 and 3.3 per cent). We conclude that p53 protein expression is not confined to follicular carcinomas; scattered p53-positive cells may also be present in histologically and clinically benign follicular adenomas. Because both follicular adenomas and carcinomas may be DNA aneuploid and their SPF and PCNA staining distributions overlap, the distinction between follicular adenoma and carcinoma should still be based on histological criteria.
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PMID:p53 protein, PCNA staining, and DNA content in follicular neoplasms of the thyroid gland. 788 88

Measures of rectal mucosal proliferation have been developed and used in research clinical settings, but their utility for larger-scale epidemiological studies remains uncertain. We assessed the suitability of bromodeoxyuridine (BrdUrd) and proliferating cell nuclear antigen (PCNA)-labeling indices (LIs) in the setting of a multicenter clinical trial of adenoma recurrence. Subjects at participating practices were asked to permit biopsy of normal rectal mucosa during a colonoscopy scheduled for other reasons. PCNA and BrdUrd labeling was performed, and corresponding LIs were computed. In general, subjects were willing to undergo biopsy during their scheduled procedures; less than 10% refused. Specimen preparation for PCNA was acceptable; the mean number of scorable crypts (+/- SE) was 12.99 +/- 0.37. Preparation for BrdUrd labeling was less successful, with a higher proportion of unscorable specimens and a lower mean number of scorable crypts. Among the 54 specimens with both LIs computed, the LI for PCNA was modestly higher than that for BrdUrd LI (4.1 +/- 0.2 and 3.7 +/- 0.2 respectively; P = 0.03). The rank order correlation between the two indices was 0.38). There was variation across centers in the PCNA LIs but few differences according to number of crypts scored. Measurement of rectal mucosal proliferation is feasible among endoscopy patients in large studies if PCNA is used; BrdUrd seems more difficult. The relationship between these two labels requires further study.
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PMID:Epidemiological use of rectal proliferation measures. 789 25

Thirteen examples of pleomorphic adenoma (PA) and 4 of myoepithelioma (Me, 2 plasmacytoid cell type, 2 mixed cell type) were examined with respect to their proliferative activity on the basis of proliferating cell nuclear antigen (PCNA) immunohistochemistry. In PA, PCNA labeling index (LI) in tubular/trabecular/solid areas was significantly higher than that in myxomatous or chondroid areas. Although the mean value of LI in PA and Me was not statistically different (PA; 3.02 +/- 1.03%, Me; 3.19 +/- 1.76%), the Me of mixed cell type composed of epithelial, spindle or clear neoplastic myoepithelial cells had significantly higher LI, indicating the possibility of more rapid growth than PA. The small difference in the mean value of PCNA LI between PA and the mixed cell type of Me, however, suggests that enucleation with a margin of normal uninvolved tissue remains the recommended treatment for Me, as well as for PA.
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PMID:Proliferative activity of salivary gland pleomorphic adenomas and myoepitheliomas as evaluated by the proliferating cell nuclear antigen (PCNA) labeling index (LI). 790 71

Binding of a specific antibody to proliferating cell nuclear antigen (PCNA) and staining of argyrophilic proteins associated with nucleolar organizer regions (AgNORs) were investigated in proliferative lesions induced by N-nitrosobis(2-oxopropyl)amine (BOP) in the hamster kidney. Thirty male Syrian golden hamsters were given three weekly s.c. injections of BOP (10 mg/kg body wt.) and sacrificed for characterization of proliferative changes 30 weeks after the first BOP treatment. Morphologically, lesions of the tubular epithelia were classified either as tubular adenoma or dysplasia, the latter being further classified into small cluster, acidophilic cell, clear cell and cystic types. Immunohistochemistry for PCNA revealed significant increases of cell proliferation activity in adenomas and acidophilic cell types of dysplasia, along with significantly elevated mean numbers of AgNORs per nucleus. The results thus indicate that the acidophilic cell type of dysplasia may be of prime significance as the preneoplastic renal lesion induced by BOP.
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PMID:Analysis of proliferative activity in renal lesions induced by N-nitrosobis(2-oxopropyl)amine (BOP) in male Syrian golden hamsters. 791 May 17

Sixty-two colorectal adenomas 10 mm or less in diameter, resected endoscopically and fixed in formalin for 3 days or less, were evaluated with antiproliferating cell nuclear antigen/cyclin (PCNA) monoclonal antibody to investigate the cell proliferation kinetics. All lesions were tubular adenoma with low-grade atypia. These lesions were classified by macroscopic type as: I; polypoid (n = 14), IIa; flat or hemispherically elevated (n = 28), IIb; plain, flat (n = 6), IIc; depressed (n = 9), and IIa+IIc slightly elevated with a central depression (n = 5). The distribution patterns of PCNA-positive cells were divided into two types; diffuse distribution of positive cells throughout the crypts (diffuse type) and localized distribution, mainly in the upper portions of the crypts (superficial type). The distribution pattern of proliferating cells was correlated with the size and macroscopic type of adenoma. Type IIc, IIa+IIc, IIb, smaller (< or = 5 mm) IIa and smaller (5 mm) I adenomas showed the superficial type pattern. Larger (> 5 mm) adenomas of type I and IIa had the diffuse type pattern. The formation of a proliferative zone in small adenomas, as in normal mucosa, but in opposite locations, suggested a lower cell proliferation activity. In the elevated type (I and IIa) adenomas, however, the change in the distribution pattern of proliferating cells from the superficial to the diffuse type would lead to growth in size.
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PMID:Proliferating cell nuclear antigen/cyclin expression in small adenomas of the large intestine in relation to size and macroscopic appearance. 791 40

Samples of normal, hyperplastic, and neoplastic parathyroid tissues were analyzed for proliferative activity to determine (1) whether a higher number of proliferating cells were detectable in adenoma and hyperplasia versus normal tissues; (2) whether there was a difference in the number of proliferating cells in adenoma versus hyperplasia; and (3) whether there was a relationship between nodularity and proliferative rate in both adenoma and hyperplasia. Formalin-fixed, paraffin-embedded tissue from 21 patients with parathyroid adenoma and 10 patients with hyperplasia (two primary, six secondary, and two tertiary) was analyzed by immunohistochemistry with the monoclonal antibody PC10 to proliferating cell nuclear antigen (PCNA) and, in a subset of cases, with Ki-67 (MIB 1) as markers of cell proliferation. The results were that (1) no proliferating cells were found in normal glands or residual rim of "suppressed" parathyroid tissue; (2) the most intense proliferative activity was confined to nodular areas in both adenomas (57% nodular) and hyperplasias (80% nodular); (3) when fields of highest number of labeled nuclei were chosen, PCNA counts were higher in adenomas than in hyperplasia in both nodular and diffuse areas (P < .05); and (4) the number of nuclei immunoreactive for Ki-67 (MIB-1) was consistently and proportionally lower (range, 13% to 45%; mean, 32%) than the number of those immunoreactive for PCNA, although the nodular pattern was maintained. These findings demonstrate that nodules within parathyroid adenomas and hyperplasias contain subpopulations of cells with a consistently higher proliferative rate than nonnodular areas. Cells within these nodules may be more likely to develop genetic abnormalities that have been observed in hyperplastic and neoplastic parathyroid tissues.
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PMID:Nodular foci in parathyroid adenomas and hyperplasias: an immunohistochemical analysis of proliferative activity. 792 9

Leptomeningeal dissemination of pituitary adenoma is a very rare occurrence. The present report describes the case of a 28 year old man with a nonfunctioning pituitary adenoma which was operated on and irradiated. Eight years later, the patient developed Cushing's syndrome and multiple leptomeningeal masses were revealed by brain CT and MNR. The diagnosis was ACTH-cell adenoma, without malignant histological signs. The growth fraction of the tumor, detected by means of the immunohistochemical demonstration of proliferating cell nuclear antigen (PCNA), was 5.45% of cells; this figure is higher than that reported for non-recurrent pituitary adenomas. From a review of the reported cases, the possibility of predicting late malignant behaviour is discussed. The microscopic aspect has no prognostic value, since metastasizing cases are not overtly malignant in a histological or cytological sense. The application of methods aimed at detecting the growth fraction of the tumor may prove useful in the early identification of aggressive pituitary tumors.
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PMID:Intracranial dissemination of pituitary adenoma. Case report and review of the literature. 796 Jun 73

The recurrence rate of pituitary adenomas has been reported to be as high as 10% to 35% despite their generally benign nature. A monoclonal antibody directed against proliferating cell nuclear antigen (PCNA) was used to investigate whether the proliferative index might help to predict adenoma recurrence. This antigen is a nuclear protein identified as the auxiliary protein of deoxyribonucleic acid polymerase delta, and its gene expression correlates with cell proliferation. The authors studied 30 patients with recurrent pituitary adenomas, 32 with nonrecurrent adenomas, and seven normal pituitary tissue samples. The mean interval to recurrence ( +/- standard error of the mean) was 5.3 +/- 0.7 years. The age- and sex-matched nonrecurrent group had a mean follow-up period of 6.6 +/- 0.3 years without clinical recurrence. Mean percentages of PCNA-positive tumor nuclei in both the initial and the second surgical specimens of the recurrent adenomas (13.45% +/- 3.02% and 19.56% +/- 3.66%, respectively) were significantly higher than that of the nonrecurrent group (2.49% +/- 1.21%). In addition, recurrent tumors had a higher PCNA index than the initial tumors in the same patients. Normal anterior pituitary gland tissue had a significantly lower mean PCNA index (0.12% +/- 0.11%) than either patient group. Stepwise multivariate regression analysis indicated that factors which collectively correlated significantly with recurrence were: high PCNA index, large tumor size, extrasellar extension, and incomplete surgical excision. The PCNA nuclear count was not associated with age, sex, or hormone hypersecretion, but was higher in macro- than in microadenomas, in tumors with extrasellar extension, and in those incompletely excised. A higher PCNA index also correlated with a shorter disease-free interval. The authors conclude that evaluation of the PCNA index assists in predicting the likelihood of pituitary adenoma recurrence.
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PMID:Significance of proliferating cell nuclear antigen index in predicting pituitary adenoma recurrence. 809 73

Immunohistochemical detection of the nuclear antigen recognised by the monoclonal antibody Ki67, DNA polymerase alpha, and the proliferating cell nuclear antigen (PCNA), and histochemical staining for the argyrophilic proteins associated with the nucleolar organizer regions (AgNOR) were carried out on histological sections from 107 colorectal adenomas containing invasive carcinoma (ACIC), including 7 with regional lymph node metastases. Separate evaluations were made for fields corresponding to adenoma with low-grade dysplasia, adenoma with high-grade dysplasia and early cancer. The same techniques were also employed in 20 cases of normal mucosa and 20 advanced carcinomas. The mean percentages of Ki67, DNA polymerase alpha, and PCNA-positive nuclei and the number of AgNOR per nucleus progressively increased along the sequence from normal mucosa via low-grade and high-grade dysplasia adenoma to advanced cancer, whereas the early cancer values were not significantly different from those in the low-grade dysplasia areas. No significant difference in PCNA positivity and number of AgNOR were noted in ACIC with and without lymph node metastases. It is suggested that the decrease in proliferative activity thus revealed in early cancer may be due to changes in the submucosa microenvironment caused by invasion, and that the metastatic potential of an early colorectal cancer cannot be correlated to such activity.
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PMID:Cell proliferation in colorectal adenomas containing invasive carcinoma. 809 91


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