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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Parathyroid carcinoma is a very rare disease occurring in less than 2-3% of all the cases showing clinical features of primary hyperparathyroidism. Several histological markers have been used for distinguishing between benign and malignant tumors of the parathyroid glands. However, most of these markers are not easily applicable and clinical prognosis cannot be predicted by histopathological criteria alone. A recent study has drawn attention to the role of the cell cycle associated antigen Ki-67 detected by MIB-1 monoclonal immunocytochemistry in parathyroid tumors: in fact, Ki-67 seems to be a valuable marker of malignancy in such tumors since it permits an easy detection of proliferating and dividing cells. Here we report in detail a case of severe recurrent hyperparathyroidism in a 51-year-old female patient undergoing regular hemodialysis treatment. In the surgical specimens of the parathyroid glands, the tumor proliferative fraction of 56, expressed as the number of Ki-67-positive nuclei per thousand cells, and the mean mitosis count of 0.5, expressed as the percentage of the total amount of Ki-67 positive nuclei, support the diagnosis of parathyroid carcinoma despite the scanty amount of microscopical signs considered characteristic of malignancy, i.e. extensive thick fibrous bands or prominent nucleoli. To our knowledge this paper is the first clinical report that supports the diagnostic role of the cell cycle associated antigen Ki-67 in parathyroid carcinoma in a case of secondary hyperparathyroidism in a patient undergoing hemodialysis.
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PMID:Recurrent secondary hyperparathyroidism due to parathyroid carcinoma: usefulness of Ki-67 immunostaining in the diagnosis of a malignant parathyroid tumor. 895 8

The diagnosis of endocervical neoplasia can be difficult as it is sometimes mimicked by proliferative or reactive glands. MIB-1 is a proliferation marker that can aid in the diagnosis of squamous intraepithelial lesions (SIL) of the cervix and vulva, but its potential value in the diagnosis of endocervical lesions has not been fully explored. Ten formalin-fixed, paraffin-embedded cases of each of the following were obtained: morphologically normal endocervical glands from patients with cervical SIL, endocervicitis, microglandular hyperplasia (MGH), and endocervical adenocarcinomas (eight in situ, two invasive). Microwave unmasking of antigens was performed prior to immunohistochemical staining for MIB-1 using the avidin/biotin peroxidase method. Labeling indexes were calculated for 34 specimens (10 adenocarcinoma. 8 each of the other diagnoses) using image analysis (Samba 4000). There was diffuse MIB-1 reactivity in adenocarcinoma (labeling index 57-96%, mean 80%), minimal focal reactivity in normal glands underlying SIL (labeling index 0.8-4.3%, mean 2.4%), moderate spotty reactivity in MGH (labeling index 2.9-18.4%, mean 8.5%), and minimal to focally diffuse reactivity in endocervicitis (labeling index 1.0-13.3%, mean 5.7%). These data indicate that the percentage and distribution of MIB-1-reactive endocervical cells can be of diagnostic utility in distinguishing neoplastic glands from those of endocervicitis and MGH.
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PMID:Quantitative image analysis of MIB-1 reactivity in inflammatory, hyperplastic, and neoplastic endocervical lesions. 898 27

Consecutive paraffin sections of 105 astrocytomas and 15 oligoastrocytomas were examined for expression of p53, MIB-1 (Ki-67), and proliferating cell nuclear antigen (PCNA). The tumors had been examined previously for genetic abnormalities and by flow cytometry. Regardless of the tumor's stage and grade and the patient's age and gender, p53 expression was found in 40% of tumors. Although p53 expression was associated with a loss on chromosome 17p and was more frequent in aneuploid tumors, it had no association with survival time. The MIB-1 and PCNA labeling indices increased with increasing tumor grade but showed no association with other clinicopathological parameters. In individual tumors, there was poor concordance between any of the variables (MIB-1, PCNA, and p53). Results for p53 and MIB-1 were similar for both astrocytomas and oligoastrocytomas. The MIB-1 and PCNA values appeared to have prognostic utility in univariate analysis but not after adjusting for patient age and tumor grade. The poor concordance between MIB-1 and PCNA in individual tumors indicates that any one means of assessing proliferative potential in gliomas may not be reliable.
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PMID:Analysis of proliferation markers and p53 expression in gliomas of astrocytic origin: relationships and prognostic value. 920 84

We report a case of composite pheochromocytoma/ganglioneuroma arising in a background of diffuse and nodular medullary hyperplasia in the adrenal gland of a 34-year-old man with multiple endocrine neoplasia 2a (MEN 2a). Cells were histologically classified as chromaffin or chromaffin-like (small typical-appearing pheochromocytoma cells), neuron-like (possessing ganglion cell morphology), and intermediate. We speculate that these cell types may represent a spectrum of differentiation of a neoplastic clone, with the intermediate cells representing a transitional stage between chromaffin cells and neurons. All three cell types in the composite tumor and all chromaffin cells in both nodular and nonnodular areas of the remaining medulla were strongly immunoreactive for tyrosine hydroxylase, the rate-limiting enzyme in catecholamine synthesis. In contrast, neuron-like cells (and to a variable extent intermediate cells) displayed selective loss of expression of phenylethanolamine-N-methyltransferase (PNMT), the enzyme that synthesizes epinephrine. Proliferative activity of the composite tumor and both the nodular and nonnodular medulla was studied by staining for the endogenous cell proliferation antigen Ki-67, using monoclonal antibody MIB-1. MIB-1 labeling was highest in Schwann cell areas of the composite tumor, followed by chromaffin-like cells in the composite tumor and in the separate nodules. Labeling was absent in neuron-like cells, consistent with the cells' postulated status as terminally differentiated derivatives of a chromaffin cell precursor, and was highly variable in nonnodular areas of the medulla. The latter observation suggests topographical variation in signals that drive chromaffin cell proliferation in MEN.
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PMID:Composite pheochromocytoma/ganglioneuroma of the adrenal gland associated with multiple endocrine neoplasia 2A: case report with immunohistochemical analysis. 899 Jan 46

Mutation of the p53 gene which is located on chromosome 17p is the single most frequent alteration observed in human cancer. In this study we evaluate malignant melanoma, the most common intraocular neoplasm in adults, for aberrant p53 expression. Twenty enucleation specimens representing one ciliary body and 17 choroidal melanomas and two choroidal nevi were studied by immunohistochemistry utilizing the D07 anti-p53 antibody and the MIB-1 monoclonal antibody. The tumors included two spindle cell and 16 mixed cell (spindle + epithelioid cell) melanomas and two spindle cell nevi. The MIB-1 labelling index ranged from < 1% (two cases), 1-5% (13 cases) and > 5% (five cases). Of the 18 melanomas, 13 cases showed nuclear p53 staining with the p53 index < 1% (two cases), 1-3% (eight cases) and 4-5% (three cases). No p53 staining was observed in two malignant melanomas of the spindle cell type and in two choroidal nevi. In the 13 malignant melanomas of the mixed cell type, there was no correlation between MIB-1 index and p53 immunoreactivity. Immunopositivity was not found in normal choroidal melanocytes. Our study suggests that p53 alterations may be found in uveal melanomas; in our series, p53 positivity was present only in malignant melanomas of the mixed cell type.
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PMID:p53 expression in uveal malignant melanomas. 900 46

The DNA content and proliferative index of 61 gastrointestinal stromal tumors (GIST) were measured by image analysis and correlated with the lesion's clinicopathological features and patient's survival. DNA analysis was performed on cytospin single-cell preparations obtained from the paraffin-embedded tissue blocks. MIB-1 was the proliferation marker used on paraffin sections. DNA aneuploidy was detected in 12 tumors (18%), and high MIB-1 index (>22%) in 12 lesions (18%). DNA aneuploidy and high MIB-1 index statistically correlated with high mitotic rate (> or = 5 x 10 high-power field [HPF]) (P < .001) and with the presence of necrosis (P < .05). The patient's survival was significantly correlated with DNA ploidy (P < .01), MIB-1 index (P < .00001), mitotic rate (P < .00001), presence of necrosis (P < .0001), and size of the tumor (P < .01). Multivariate regression analysis showed that only MIB-1 index was an independent parameter in predicting the clinical outcome for patients with GIST. The mitotic rate was the only other independent prognostic factor when MIB-1 index was not allowed to enter the model.
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PMID:Prognostic significance of DNA ploidy and proliferative index (MIB-1 index) in gastrointestinal stromal tumors. 944 44

In lung carcinomas, the proliferative activity, as detected by Ki-67 antigen immunostaining of surgical specimens, is a valuable factor predicting clinical evolution and response to treatment. We investigated whether bronchial endoscopic and fine-needle aspiration (FNA) biopsies of lung carcinoma can provide a reliable estimation of the tumor proliferative fraction (TPF). In 66 resectable lung carcinomas, sections of preoperative bronchial or FNA biopsies and the corresponding surgical specimens were stained in parallel for Ki-67 using MIB-1 monoclonal. The mean TPF was 44.7% in the surgical specimens, 40.3% in bronchial biopsies, and 26.3% in FNAs. When the scores of biopsy and resected specimen of each individual tumor were compared, a significant correlation between the TPFs of preoperative and postoperative specimens was found (r = .79). In both biopsy and surgical specimens, a high TPF was associated with squamous cell carcinoma histological type and high-grade (poorly differentiated) tumors. In addition, a significantly (P < .05) lower disease-free interval was found in patients affected by highly proliferating tumors (irrespective of the tumor stage). We conclude that the proliferative activity of lung cancer can be reliably assessed in bronchial or FNA biopsies. This information could help to select chemotherapy protocols in nonresectable lung carcinomas.
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PMID:Value of Ki-67 immunostaining in preoperative biopsies of carcinomas of the lung. 902 1

Tumor progression and clinical outcome for patients with renal cell carcinomas (RCCs) cannot be predicted based solely on tumor staging and grading. In a retrospective study we have therefore attempted to analyze the capacity of proliferation markers to provide additional prognostic information. One hundred seven cases of RCC were investigated by immunohistochemical analysis using two different monoclonal antibodies: PC10, which recognizes a proliferating cell nuclear antigen (PCNA), and MIB-1, which identifies the Ki-67 antigen in formalin-fixed, paraffin-embedded material. PCNA frequency ranged from 0% to 71% (mean, 17%), and MIB-1 expression, from 0% to 43% (mean, 11%). PCNA scores correlated significantly with MIB-1 immunoreactivity. PCNA and MIB-1 immunoreactivity showed a significant correlation with tumor grade. A strong correlation was also observed for T-component of stage and MIB-1 scores, but no correlation was found between PCNA and T-component of stage. In univariate analysis, PCNA immunoreactivity and MIB-1 scores were significant predictors of survival. Multivariate analysis, using a Cox proportional hazard model, showed PCNA index, N-component of stage, and tumor grade to be independent predictors of tumor progression, which is not the case for MIB-1 index.
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PMID:Proliferating cell nuclear antigen and MIB-1. An alternative to classic prognostic indicators in renal cell carcinomas? 902 73

Patients with neurofibromatosis 2 (NF2) are predisposed to a variety of neoplastic and dysplastic lesions, including schwannomas, neurofibromas, meningiomas, astrocytomas, and ependymomas, as well as entities such as meningioangiomatosis, schwannosis, and hamartomas. This study reports a unique intracerebral frontotemporal tumor in a 6-year-old boy with presumed NF2, on the basis of bilateral cerebellopontine tumors consistent with acoustic neuromas. The intracerebral tumor revealed a variety of histological patterns, including foci of primitive neuroectodermal tumor (PNET), low-grade astrocytoma and ependymoma, as well as neuroepithelial rests with immature ganglion cells and hamartomatous areas. The MIB-1 labeling index ranged from 63% in the foci of PNET to 4-7% in other foci. The PNET component revealed immunopositivity for synaptophysin and neurofilament and showed cells with delicate intercellular junctions, profiles of rough endoplasmic reticulum, mitochondria, and dense core granules, and cell processes with microtubules and neurofilaments. The glial and ependymal components showed bundles of glial filaments and prominent cell junctions, cilia, and microvilli. The hamartomatous component also included aggregates of cells with hyaline eosinophilic cytoplasm. By EM these cells contained abundant amorphous flocculent material. This constellation of pathologic findings, especially the finding of PNET, is unique and not previously reported in the setting of NF2.
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PMID:Unique intracerebral tumor with divergent differentiation in a patient presenting as NF2: report of a case with features of astrocytoma, ependymoma, and PNET. 902 67

We considered of interest to determine the possible interrelationship between the proliferation-related marker MIB-1/Ki-67 and the bcl-2, a protein involved in the blockage of apoptosis, and whether they contributed to the prognosis of breast cancer. For this purpose we carried out a retrospective immunohistochemical study of 238 cases of stage I and II breast carcinomas with a follow up of at least 5 years. The study revealed that high expression of MIB-1 was associated with high nuclear and histological grades (p < 0.001 for both), negative estrogen receptor status (p = 0.009) and progesterone status (p = 0.004), and younger age (p = 0.014). High bcl-2 expression was associated with smaller tumor size (p = 0.001), positive estrogen and progesterone receptors (p < 0.001 for both); low nuclear grade (p < 0.001), low histological grade (p < 0.002), stage I disease (p = 0.01) and low MIB-1 expression (p = 0.025). The univariate Cox regression showed a significant association of high MIB-1 expression (p = 0.002) and low bcl-2 expression (p = 0.04) with shorter OS. Furthermore, MIB-1 expression was a significant independent predictor of OS (p = 0.002) as showed by stepwise Cox regression analysis.
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PMID:[Immunohistochemical detection of bcl-2 and MIB-1/Ki-67 in breast cancer: retrospective analysis of 238 cases]. 903 81


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