Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “HYPERPLASIA”

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 289 records · Page 16Linked to original sources
PubMed2005

Sporadic Cajal cell hyperplasia is common in resection specimens for distal oesophageal carcinoma. A retrospective review of 77 consecutive surgical resection specimens.

Interstitial cell of Cajal (ICC) hyperplasia has been documented in conditions associated with multiple gastrointestinal stromal tumours (GISTs) (familial GIST syndromes, Carney's triad and von Recklinghausen's disease) and rarely in the vicinity of sporadic GISTs. The incidence of sporadic ICC hyperplasia and the so-called seedling leiomyoma (SLM) of the lower oesophagus has not been studied in the KIT era. In a retrospective review of 77 consecutive, routinely processed oesophagogastric resection specimens for distal oesophageal carcinoma, we found foci of ICC hyperplasia in 7 of 77 (9.1%) cases and foci of SLM in 17 of 77 (22%) cases. Two types of ICC hyperplasia were recognized: a non-circumscribed type and a nodular expansile type with peripherally compressed myenteric neural tissues. All cases of ICC hyperplasia were vimentin+/CD34+/CD117+. SLMs were desmin+/vimentin(-)/CD34(-)/CD117(-), similar to smooth muscles of the gut wall. In a prospective study of 32 non-carcinomatous specimens from age-matched patients (mostly autopsy cases), we found SLMs in only one case, but we were unable to detect ICC hyperplasia in any of the cases. We concluded that sporadic KIT-positive spindle-cell hyperplasia and SLMs were unexpectedly common in distal oesophageal specimens harbouring carcinomas. The possible mechanisms leading to the development of these putative precursor lesions will be discussed.

Adenocarcinoma↗
PubMed2004

Localization of islet-cell hyperplasia: value of pre- and intraoperative arterial stimulation and venous sampling.

Arterial stimulation and venous sampling was effective in the localization of Beta-cell hyperplasia of the pancreas in the islets of Langerhans in an 84-year-old woman. The patient presented with repeated episodes of unconsciousness and hypoglycemia. She was first suspected of having insulinoma, but diagnostic imaging failed to reveal any tumors. Arterial stimulation and venous sampling (ASVS) and percutaneous transhepatic portal venous sampling (PTPS) were performed to localize the tumor. By ASVS, increases in immuno reactive insulin (IRI) were noted in renal vein blood samples (because a splenorenal shunt was present) after splenic arterial stimulation and venous sampling, and PTPS revealed a stepup in IRI from splenic venous blood samples. Preoperative diagnosis suggested Beta-cell hyperplasia in the pancreas tail. Intraoperative ultrasound failed to find a tumor. Intraoperative ASVS showed the site of increase IRI as the pancreas tail, so distal pancreatectomy and splenectomy were performed. However, hypoglycemia was observed constantly after this operation. Relaparotomy, causing additional resection, was conducted to confirm the precise location and to remove the residual Beta-cell hyperplasia of the pancreas. At the second resection, the existing part of Beta-cell hyperplasia was confirmed through intraoperative ASVS, and additional resection of the pancreas body and neck was performed. At this time, complete removal of the residual Beta-cell hyperplasia was confirmed through ASVS. The hypoglycemia and impaired consciousness disappeared after the operation, and the patient's blood sugar level was maintained at a normal level. Pathological findings revealed islets of Langerhans hyperplasia extending to 1 cm in the pancreas tail region. We conclude that pre- and intraoperative ASVS is a useful test for Beta-cell hyperplasia, which is difficult to diagnose through ordinary imaging techniques.

Aged↗
PubMed2005

Disorders in cytokine gene expression in endometrial hyperplasia and effect of hormone therapy.

We studied local expression of insulin-like growth factor 1, insulin-like growth factor receptor, epithelial growth factor, transforming growth factor beta2, PCNA, TNF-alpha, type I TNF receptor, Fas, FasL, IFN-gamma, IL-1beta, IL-4, IL-6, IL-8, IL-10, and IL-12 genes in intact and hyperplastic endometrium. Endometrial hyperplasia was associated with reduced production of TNF-alpha (p<0.05), PCNA (p<0.05), and epithelial growth factor mRNA and enhanced production of Fas mRNA (p<0.01). The expression of TNF-R1, IL-1beta, and IL-12 genes decreased only in glandular cystic hyperplasia (p<0.05 for all genes), expression of insulin-like growth factor 1 gene decreased only in adenomatous hyperplasia (p<0.05). Dufaston therapy of glandular cystic hyperplasia and zoladex therapy of adenomatous hyperplasia normalized expression of Fas receptor, PCNA, and insulin-like growth factor 1 genes, while the expression of IFN-gamma and IL-6 genes, which was normal in hyperplasia, decreased (p<0.05). Zoladex therapy decreased the production of transforming growth factor beta2 (p<0.05) and IL-1beta (p<0.01) mRNA, dufaston therapy decreased production of TNF-alpha (p<0.05) and IL-4 mRNA (p<0.05). Hence, both apoptosis and proliferative activity were suppressed in endometrial hyperplasia, and hormone therapy created prerequisites for transition of the endometrium into the normal proliferation stage.

Apoptosis↗
PubMed1981

Nodular regenerative hyperplasia of the liver associated with macroglobulinemia. A clue to the pathogenesis.

Nodular regenerative hyperplasia of the liver is an infrequent condition characterized by transformation of the hepatic parenchyma into nodules with only mild fibrosis. Little is known about the etiology except that there is usually an underlying chronic disease, such as Felty's syndrome, which antedates the development of clinical liver disease. It is poorly understood how the associated diseases contribute to the pathogenesis of nodular regenerative hyperplasia. Presented are four cases of nodular regenerative hyperplasia in which macroglobulinemia was also present. This new association suggests to us a hypothesis for the pathogenesis of nodular regenerative hyperplasia. Histologic examination of the livers in these and other cases of nodular regenerative hyperplasia reveals widespread obliteration of the small portal veins. Postmortem angiography of one liver in the present series demonstrated that the nodules were well perfused and that the atrophic areas were poorly perfused with portal blood. This supports the view that atrophy of lobules results from a lack of portal blood supply and that nodules develop from lobules well supplied with portal blood. In each of the clinical conditions associated with nodular regenerative hyperplasia, including macroglobulinemia, inflammatory or thrombotic vascular lesions are found in many organs. Therefore, nodular regenerative hyperplasia may be the hepatic expression of a more widespread vascular disease.

Adult↗
PubMed1986

Clinical and pharmacologic correlations in cyclosporine-induced gingival hyperplasia.

Cyclosporine-induced gingival hyperplasia was investigated in a clinical study of 100 patients over a period of 2 1/2 years. Seventy percent of the patients exhibited at least mild gingival hyperplasia. For doses within the therapeutic range, no direct correlation was found between the oral dose or the serum trough concentration of cyclosporine and the severity of gingival hyperplasia. The presence of dental plaque was found to be related to the presence of gingival hyperplasia, but only a weak correlation existed between the abundance of plaque and the severity of gingival hyperplasia. Children and especially adolescents had a greater risk of developing cyclosporine-induced gingival hyperplasia than adults had. In 21 patients followed for 1 to 18 months after cessation of cyclosporine therapy, induced gingival hyperplasia was found to be clinically reversible.

Adolescent↗
PubMed1991

Expression of ABH blood group antigens, receptors of Ulex europaeus agglutinin I, and factor VIII-related antigen on sinusoidal endothelial cells in adenomatous hyperplasia in human cirrhotic livers.

Adenomatous hyperplasia, a hyperplastic parenchymal nodule in the cirrhotic liver, has been presumed to be a preneoplastic lesion in human hepatocarcinogenesis. In this study, phenotypes of the sinusoidal endothelium were examined in adenomatous hyperplasia, hepatocellular carcinoma, cirrhosis, chronic active hepatitis, and normal livers. Adenomatous hyperplasia (n = 74) was histologically classified into two types: ordinary (n = 35) and atypical (n = 39). While the former lacked hepatocellular atypia, the latter consisted of atypical hepatocytes equivocal as to benignity and malignancy, in some of which overt malignant foci were found. The expression of A, B, and H blood group antigens, receptors of Ulex europaeus agglutinin I, and factor VIII-related antigen on the sinusoidal endothelium was minimal or nil in normal livers. It was mild and focal in chronic active hepatitis, cirrhosis, and ordinary adenomatous hyperplasia, while expression was moderate in atypical adenomatous hyperplasia with or without malignant foci, and severe in malignant foci in atypical adenomatous hyperplasia and in hepatocellular carcinoma. These data suggest that phenotypes of the sinusoidal endothelium of atypical adenomatous hyperplasia are closely related to the development of hepatocellular carcinoma, and phenotypic changes of the sinusoidal endothelium occur stepwise corresponding to various stages of hepatocarcinogenesis in cirrhotic livers.

ABO Blood-Group System↗
PubMed1994

Nodular foci in parathyroid adenomas and hyperplasias: an immunohistochemical analysis of proliferative activity.

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.

Adenoma↗
PubMed1995

Small stent size and intimal hyperplasia contribute to restenosis: a volumetric intravascular ultrasound analysis.

OBJECTIVES: The purpose of this study was to use volumetric intravascular ultrasound analysis of Palmaz-Schatz stents to assess the in-stent restenotic process. BACKGROUND: By reducing lesion elastic recoil and chronic arterial remodeling, stents improve the long-term results of coronary angioplasty. However, stents are prone to the development of neointimal hyperplasia. Angiographic studies of stent restenosis have suggested that these hyperplastic responses are the cause of in-stent restenosis; however, it is difficult to visualize the radiolucent Palmaz-Schatz stent by angiography. Intravascular ultrasound provides detailed cross-sectional imaging of the coronary arteries, especially the intense metallic reflection of endovascular stents. METHODS: Forty-four patients with 60 Palmaz-Schatz stents underwent intravascular ultrasound imaging at follow-up ([mean +/- SD] 8.8 +/- 7.2 months after implantation). Thirty-four stents were placed in saphenous vein grafts and 26 in native coronary arteries; 30 were placed in restenotic lesions. Intravascular ultrasound with automatic transducer pullback at 0.5 mm/s allowed measurement of stent, lumen and intimal hyperplasia cross-sectional areas at 1-mm axial increments within the stents. Using Simpson's rule, stent, lumen and intimal hyperplasia volumes were calculated. Patterns of in-stent restenosis were then identified. RESULTS: Restenotic stents had smaller stent volumes (120 +/- 41 vs. 147 +/- 43 mm3, p = 0.016) and lumen volumes (62 +/- 28 vs. 118 +/- 42 mm3, p < 0.0001) but larger intimal hyperplasia volumes (58 +/- 36 vs. 29 +/- 18 mm3, p < 0.001) than nonrestenotic stents. A focal restenosis pattern was more common (20 [77%] of 26) than a diffuse restenosis pattern (6 [23%] of 26). Stents with focal restenosis and stents with diffuse restenosis had equally small stent volumes (120 +/- 44 vs. 120 +/- 31 mm3, respectively, p = NS); however, stents with diffuse restenosis had larger intimal hyperplasia volumes (84 +/- 30 vs. 50 +/- 34 mm3, p < 0.05). Focal restenosis was most commonly located at the central articulation (45%); the location of focal restenosis was related to the focal accumulation of neointimal tissue. CONCLUSIONS: Stent volume and magnitude and distribution of intimal hyperplasia are important in the development of in-stent restenosis. Stent volume was smaller and intimal hyperplasia volume greater in restenotic stents. Stent restenosis is more commonly focal in nature and located at the central articulation.

Aged↗
PubMed2006

The significance of surgical margins for patients with atypical ductal hyperplasia.

BACKGROUND: The significance of surgical margins for patients with atypical ductal hyperplasia is unknown. PATIENTS AND METHODS: We reviewed our experience with atypical ductal hyperplasia and correlated the margin status of the specimens removed with the risk of recurrence as atypical ductal hyperplasia, ductal carcinoma in situ, and invasive carcinoma. Seven hundred forty-seven patients were identified between February 1995 and September 2005 as having biopsy proven atypical ductal hyperplasia (ADH). One hundred fifty-five of these patients were found to have "pure" atypical ductal hyperplasia without associated premalignant or malignant breast disease or a history of ipsilateral disease. Margin status of the initial excisional biopsy was noted and was correlated with the risk of recurrence. RESULTS: Of the 155 patients whose excisional biopsy specimens were "pure" atypical ductal hyperplasia, 44% (68) had negative margins, 5% (7) had positive margins, and 52% (80) were not reported. No patient underwent re-excision for close or positive margins. Follow-up ranged from 0 to 119 months, with a mean of 26 months. Seven patients (5%) presented with new findings at the site of their initial excisional biopsy, 1 of whom was found to have an invasive ductal carcinoma and 6 of whom had benign findings. Of the 87 patients with margins positive or unknown for ADH at surgical excision, none went on to develop malignancy. CONCLUSION: Our results suggest that clear surgical margins at surgical excision for atypical ductal hyperplasia did not affect the risk of subsequently developing a malignancy.

Adult↗
PubMed2005

Can flowcytometric DNA studies forecast the prognosis of endometrial hyperplasia?

OBJECTIVES: The study is investigating the relation of the ploidy pattern and cell cycle kinetics to different types of endometrial hyperplasia to select the high-risk women who will need strict follow up surveillance. STUDY DESIGN: An observational study of 152 patients with endometrial hyperplasia. Endometrial samples were subjected to flowcytometric study of the nuclear DNA content to determine the ploidy pattern and cell cycle kinetics. RESULTS: The mean age of women was 46.3+/-3.6 years. 15.8% of women were nulliparae, 36.8% were diabetic and 43.6% were hypertensive. 48.7% of women were obese (BMI>30). Most of endometrial samples (88.2%) were simple endometrial hyperplasia without atypia. The cell cycle kinetics in different types of endometrial hyperplasia shows that there were significant statistical differences as regards the S-phase fraction and proliferative index (PI) between typical and atypical hyperplasia. CONCLUSION: The study of cell cycle kinetics by flowcytometry might help in picking up, among all women with endometrial hyperplasia, the group of patients who need further close and strict follow up by endometrial pathologic study. This is going to minimize the cost and invasiveness of surveillance of patients with various grades of endometrial hyperplasia.

Adult↗
PubMedDate not supplied

Hysteroscopic view in atypical endometrial hyperplasias: A correlation with pathologic findings on hysterectomy specimens.

STUDY OBJECTIVE: To evaluate whether hysteroscopic imaging can contribute to decrease the rate of undetected endometrial carcinomas concurrent with atypical hyperplasia diagnosed by endometrial biopsy. DESIGN: Retrospective study. DESIGN CLASSIFICATION: Canadian Task Force Classification II-3. SETTING: Public hospital. PATIENTS: Hysteroscopic reports of 25 menopausal patients undergoing endometrial biopsy yielding a diagnosis of atypical hyperplasia were reviewed. On the basis of this diagnosis, all patients were treated by hysterectomy, and the pathologic findings on the uterine specimen were correlated with the diagnoses obtained by hysteroscopic view. INTERVENTIONS: Hysteroscopy was video-assisted and carried out with normal saline solution used as liquid distension medium; a 5-mm sheathed hysteroscope, with a working channel, was used for each examination. After hysteroscopic inspection, an endometrial sampling targeted under vision was performed by mechanical or electrosurgical instrumentation. When extensive features of hyperplastic or neoplastic growth were observed, we combined a blind sampling procedure with Vabra-curettage. We calculated the sensitivity, specificity, and negative and positive predictive values of hysteroscopic inspection to foresee the diagnosis of endometrial cancer incidentally detected on hysterectomy specimen. MEASUREMENTS AND MAIN RESULTS: On the basis of histopathologic study of uterine specimens, non atypical hyperplasias were detected in 3 patients, the diagnosis of complex atypical hyperplasia was confirmed in 11 patients, whereas a concurrent infiltrating endometrial adenocarcinoma was detected in 11 patients (44.0%). In the 14 patients with diagnosis of endometrial hyperplasia, no feature suggesting endometrial malignancy was reported by hysteroscopic inspection. In the 11 cases showing infiltrating carcinomas, hysteroscopic view was consistent with endometrial malignancy in 9 patients and with endometrial hyperplasia in 2 patients. An intramucous endometrial carcinoma without evidence of myometrial invasion was found on hysterectomy specimens of these two latter patients. From these figures, sensitivity, specificity, and negative and positive predictive values of hysteroscopy to foresee a diagnosis of infiltrating carcinoma were 84.6%, 100%, 87.5%, and 100%, respectively. CONCLUSIONS: Hysteroscopic view is a sensitive and specific method to identify among patients with a diagnosis of atypical hyperplasia on endometrial biopsy those with a coexisting infiltrating carcinoma.

Adenocarcinoma↗
PubMedDate not supplied

Validation of hysteroscopic view in cases of endometrial hyperplasia and cancer in patients with abnormal uterine bleeding.

STUDY OBJECTIVE: To validate hysteroscopic view with histology in cases of endometrial hyperplasia and cancer in patients with abnormal uterine bleeding (AUB) DESIGN: Retrospective study (Canadian Task Force classification II-3). SETTING: University teaching hospitals in Rio de Janeiro and São Paulo, and private office in Rio de Janeiro. PATIENTS: Four thousand and fifty-four patients with AUB in whom hysteroscopic views were complete and the histologic result was conclusive. INTERVENTION: Four thousand and fifty-four office hysteroscopies with complete views and conclusive histologic results. The material for histologic examination was obtained through biopsy of the lesion in an outpatient unit or through the resection of the entire lesion in patients who underwent surgery. Histology was considered the "gold standard" and compared with the hysteroscopic view. MEASUREMENTS AND MAIN RESULTS: In the histology of the 4054 examinations, 613 (15.2%) were endometrial hyperplasia, and 105 (2.6%) were endometrial cancer. The most frequent hysteroscopic finding was endometrial polyps (31.2%). In endometrial hyperplasia, the sensitivity of the hysteroscopic view was 56.3% (95% CI 52.2%-60.2%), specificity was 89.1% (95% CI 88.0%-90.1%), positive predictive value (PPV) was 48.0% (95% CI 44.3%-51.7%), negative predictive value (NPV) was 92.0% (95% CI 90.1%-92.9%), and accuracy was 72.7% (95% CI 70.7%-74.7%). Accuracy was defined as the proportion of correct results among the hysteroscopic examinations. In endometrial cancer, the sensitivity of the hysteroscopic view was 80.0% (95% CI 71.1%-87.2%), specificity was 99.5% (95% CI 99.2%-99.7%), PPV was 81.5% (95% CI 72.7%-88.5%), NPV was 99.5% (95% CI 99.2%-99.7%), and accuracy was 89.8% (95% CI, 85.9%-93.6%). In the 814 patients (20.0%) in whom the hysteroscopic view was normal, there were no false negatives for endometrial cancer; however, there were 37 (4.5%) false negatives for endometrial hyperplasia. In the histologic cases of endometrial cancer, 101 (96.2%) hysteroscopic views were compatible with cancer or hyperplasia (80.0% and 16.2%, respectively). Ninety-seven out of 103 hysteroscopic views with cancer findings (94.2%) had histologic diagnosis of cancer or hyperplasia (81.5% and 12.6%, respectively). CONCLUSION: It seems that even in face of good validity of hysteroscopic view for endometrial hyperplasia and cancer, histologic study is mandatory in the presence of any lesion as the hysteroscopic view cannot completely replace the histologic study in patients with AUB.

Adult↗
PubMed2004

Recombinant human thrombomodulin inhibits arterial neointimal hyperplasia after balloon injury.

OBJECTIVE: Smooth muscle cell proliferation is a major pathophysiologic factor in injury-induced neointimal hyperplasia and recurrent stenosis. We have demonstrated that recombinant human thrombomodulin (rTM) inhibits thrombin-induced arterial smooth muscle cell proliferation in vitro. The purpose of this study was to investigate the effect of rTM on neointimal hyperplasia in vivo. METHODS: A rabbit femoral artery balloon injury model was used. Bilateral superficial femoral arteries were deendothelialized with a 2F arterial embolectomy catheter. rTM (145 microg/kg; 2.0 microg/mL in circulation) or Tris-hydrochloride vehicle control was administered intravenously during the procedure, then either discontinued (group A) or administered twice daily for an additional 48 hours (group B). Rabbits were euthanized at 4 days and at 1, 2, and 4 weeks, and femoral artery specimens were prepared with in situ perfusion fixation and paraffin embedding. Luminal, intima, media, and whole artery areas were quantitated with digital imaging computerized planimetry. Intima-media and lumen-whole artery ratios were calculated. The injury-induced inflammatory reaction was also evaluated with light microscopy, scanning and transmission electron microscopy, and immunohistochemical and immunohistofluorescence staining. RESULTS: In the buffer control group, neointimal hyperplasia after femoral artery balloon injury was evident at 2 weeks, and was pronounced at 4 weeks (P <.0001). Infusion of rTM significantly inhibited intimal hyperplasia at both 2 and 4 weeks (P <.0001). In group A, rTM reduced the intima-media ratio by 27% and 39% at 2 and 4 weeks, respectively. Extended administration of rTM (group B) resulted in inhibition of hyperplasia by 57% and 30% at 2 and 4 weeks, respectively, but failed to reach significance compared with the shorter exposure. rTM infusion significantly inhibited thrombosis (8.1-fold) compared with the buffer control group (P =.012). rTM had no significant effect on lumen area or lumen-whole artery ratio, but treated arteries demonstrated significantly less compensatory dilatation (P =.045), as measured by whole artery area in response to less intimal hyperplasia. rTM administration inhibited platelet adhesion and inhibition of neutrophil infiltration to a degree that approached statistical significance (P =.0675). CONCLUSIONS: Systemic intravenous administration of rTM significantly decreases neointimal hyperplasia and improves patency in the rabbit femoral artery after balloon injury. In addition to exhibiting antithrombotic and antiproliferative effects, rTM may also invoke an anti-inflammatory mechanism, and may alter vascular remodeling in a multidimensional role to inhibit recurrent stenosis after arterial injury.

Angioplasty, Balloon↗
PubMed2004

Small-caliber heparin-coated ePTFE grafts reduce platelet deposition and neointimal hyperplasia in a baboon model.

PURPOSE: Intimal hyperplasia and graft thrombosis are major causes of graft failure. Heparin prolongs graft patency and inhibits neointimal hyperplasia in animal models. The purpose of this study was to evaluate the effect of a heparin-coated expanded polytetrafluoroethylene (ePTFE) graft on platelet deposition and anastomotic neointimal hyperplasia after aortoiliac bypass grafting in a baboon model. METHODS: Heparin-coated ePTFE grafts (4-mm diameter) were incorporated into exteriorized femoral arteriovenous shunts placed in five baboons. Platelet deposition was analyzed by measuring the accumulation of indium 111-labeled platelets on the grafts, with dynamic scintillation camera imaging. Eight adult male baboons (mean weight, 9.3 kg) underwent bilateral aortoiliac bypass grafting with ePTFE grafts (4-mm internal diameter). In each animal a heparin-coated ePTFE graft was placed in one aortoiliac artery, and an uncoated graft, which served as the control, was placed in the contralateral aortoiliac artery. All grafts were harvested at 4 weeks, and were analyzed quantitatively for neointimal hyperplasia at graft-vessel anastomoses. RESULTS: Early platelet deposition on heparin-coated grafts after 1 to 4 hours of ex vivo circuitry was significantly reduced. All the harvested aortoiliac grafts were patent at 4 weeks. There was a significant reduction in neointimal area at both proximal (0.26 +/- 0.11 mm(2)) and distal (0.29 +/- 0.14 mm(2)) anastomoses in the heparin-coated grafts, compared with proximal (0.56 +/- 0.18 mm(2)) and distal (0.63 +/- 0.21 mm(2)) anastomoses in the untreated control grafts (P <.05). In addition, neointimal cell proliferation assayed with bromodeoxyuridine (BrdU) incorporation was reduced in the graft neointima (3.47% +/- 0.43%) in heparin-coated grafts compared with the graft neointima (6.21% +/- 0.59%) in untreated control grafts (P <.05). CONCLUSIONS: Small-caliber heparin-coated ePTFE grafts significantly reduce platelet deposition and anastomotic neointimal hyperplasia and cell proliferation, without measurable side effects, in baboons. Surface coating with heparin in small-caliber ePTFE grafts is useful for improving prosthetic bypass graft patency. CLINICAL RELEVANCE: An autologous vein graft is the ideal bypass conduit in peripheral arterial reconstruction; however, many patients who undergo bypass grafting do not have adequate or available autologous vein graft. As a result surgeons often must rely on prosthetic grafts as an alternative conduit in arterial bypass procedures. Clinical outcomes with prosthetic grafts in peripheral arterial reconstruction are generally inferior to those with autologous vein bypass grafts, in part because of anastomotic neointimal hyperplasia. This study evaluated the effect of small-caliber heparin-coated expandable polytetrafluoroethylene (ePTFE) grafts in aortoiliac reconstruction in a baboon model. The study found that heparin-coated ePTFE grafts resulted in less intimal hyperplasia and less platelet deposition after implantation, compared with noncoated control ePTFE grafts.

Anastomosis, Surgical↗
PubMed2005

Estrogen and progesterone receptors and cyclooxygenase-2 expression in endometrial cancer, endometrial hyperplasia, and normal endometrium.

OBJECTIVES: To determine whether cyclooxygenase-2 (COX-2) expression is seen in endometrial cancer, endometrial hyperplasia, and normal endometria and whether it correlates with expression of estrogen and progesterone receptors. METHODS: The study was a retrospective, IRB-approved analysis of biopsy samples from 14 patients with endometrial adenocarcinoma, 19 with endometrial hyperplasias, and 10 with normal endometrium. Excluded were samples from women with a history of pelvic radiation, NSAID use, or treatment with hormones during previous year. Immunohistochemical analyses were performed on formalin-fixed, paraffin-embedded tissues. Expression of COX-2, estrogen and progesterone receptors were scored according to the proportion of positive-staining cells: 1(+), <10%; 2(+), 10-50%; and 3(+), >50%. A score > or =2(+) was considered positive. Fisher's exact test and analysis of variance were used to compare proportions and continuous variables, respectively. RESULTS: Overexpression of COX-2 was seen in 4 (29%) of the endometrial cancers, 6 (32%) of the endometrial hyperplasia, and 4 (20%) of the normal endometria. These differences were not statistically significant (P = 0.90). No COX-2 expression was found in stromal tissue. Of 14 endometrial cancers, 7 (50%) expressed any COX-2, with 4 (29%) having an expression score of > or =2(+). Of 19 endometrial hyperplasias, 11 (58%) expressed any COX-2; with 6 (32%) having a score of > or =2(+). All 10 normal endometria showed only 1(+) expression. No significant differences were detected in COX-2 expression by grade or stage of cancer. Although 100% and 95% of both hyperplasia and normal endometrium samples expressed in estrogen and progesterone receptors, respectively, only 71% and 79% of endometrial cancers expressed estrogen and progesterone receptors (P = 0.01). A nonparametric trend was performed to detect a relationship, between COX-2 and estrogen receptor or progesterone receptor expression; no significant trend was found. CONCLUSIONS: In this study, the immunohistochemical analysis showed a trend toward increased COX-2 expression in endometrial cancer and hyperplasia compared to normal endometria. A larger sample size is needed to confirm these results. The increased COX-2 expression in hyperplasia may signify an early step in carcinogenesis. These findings may represent an important treatment opportunity for synergism in the hormonal therapy of endometrial cancer.

Adult↗
PubMed2001

Extent and distribution of in-stent intimal hyperplasia and edge effect in a non-radiation stent population.

Intimal hyperplasia within the body of the stent is the primary mechanism for in-stent restenosis; however, stent edge restenosis has been described after brachytherapy. Our current understanding about the magnitude of in vivo intimal hyperplasia and edge restenosis is limited to data obtained primarily from select, symptomatic patients requiring repeat angiography. The purpose of this study was to determine the extent and distribution of intimal hyperplasia both within the stent and along the stent edge in relatively nonselect, asymptomatic patients scheduled for 6-month intravascular ultrasound (IVUS) as part of a multicenter trial: Heparin Infusion Prior to Stenting. Planar IVUS measurements 1 mm apart were obtained throughout the stent and over a length of 10 mm proximal and distal to the stent at index and follow-up. Of the 179 patients enrolled, 140 returned for repeat angiography and IVUS at 6.4 +/- 1.9 months and had IVUS images adequate for analysis. Patients had 1.2 +/- 0.6 Palmaz-Schatz stents per vessel. There was a wide individual variation of intimal hyperplasia distribution within the stent and no mean predilection for any location. At 6 months, intimal hyperplasia occupied 29.3 +/- 16.2% of the stent volume on average. Lumen loss within 2 mm of the stent edge was due primarily to intimal proliferation. Beyond 2 mm, negative remodeling contributed more to lumen loss. Gender, age, vessel location, index plaque burden, hypercholesterolemia, diabetes, and tobacco did not predict luminal narrowing at the stent edges, but diabetes, unstable angina at presentation, and lesion length were predictive of in-stent intimal hyperplasia. In a non-radiation stent population, 29% of the stent volume is filled with intimal hyperplasia at 6 months. Lumen loss at the stent edge is due primarily to intimal proliferation.

Coronary Disease↗
PubMed2001

Molecular cytogenetic comparison of apocrine hyperplasia and apocrine carcinoma of the breast.

The relationship of apocrine metaplasia to invasive breast cancer is controversial. Different authors have reported that apocrine differentiation in proliferative lesions may be a risk factor, a precursor lesion, or have no association with malignancy. The aim of this study was to compare the genetic alterations in benign apocrine hyperplasia with apocrine ductal carcinoma in situ (DCIS) and invasive apocrine carcinomas of the breast using comparative genomic hybridization. The mean number of alterations in apocrine hyperplasia was 4.1 (n = 10) compared to 10.2 in apocrine DCIS (n = 10) and 14.8 (n = 4) in invasive carcinoma. The most common alterations in apocrine hyperplasia were gains of 2q, 13q, and 1p and losses of 1p, 17q, 22q, 2p, 10q, and 16q. Apocrine DCIS and invasive carcinomas showed gains of 1q, 2q, 1p, and losses of 1p, 22q, 17q, 12q, and 16q as their most common DNA copy number changes. Apocrine hyperplasia is considered to be a benign lesion and its relationship to invasive carcinoma remains unclear. Our data suggest that some apocrine hyperplasias may be clonal proliferations. The mean number of alterations are lower in apocrine hyperplasia, however the changes show considerable overlap with those identified in in situ and invasive apocrine carcinoma. These alterations are also commonly seen in nonapocrine breast cancer. The data are consistent with apocrine hyperplasia as a putative nonobligate precursor of apocrine carcinoma.

Adult↗
PubMed2003

PyV-mT-induced parotid gland hyperplasia as detected by altered lectin reactivity is not modulated by inducible nitric oxide deficiency.

The parotid gland was one of the first organs recognised to be sensitive to the transforming effects of polyomavirus. This study examines parotid gland pathology in mice expressing the polyomavirus middle T (PyV-mT) under the control of the mouse mammary tumour virus long terminal repeat (MMTV-LTR) to (1) demonstrate the utility of this model for studying premalignant disease; (2) identify early lesions by lectin staining and (3) determine effects of the inducible nitric oxide synthase (iNOS) in modulating tumorigenesis. The middle T oncogene is expressed in the parotid glands in addition to the mammary glands and results in the formation of parotid hyperplasias in 100% of transgenic female mice. These hyperplasias have the features of intraepithelial neoplasia including hypertrophic cells with prominent nucleoli and abnormal mitoses. Focal areas of parotid hyperplasia can be identified using peanut agglutinin (PNA), a lectin that recognises the tumour associated T antigen. In contrast to normal parotid gland, areas of hyperplasia do not bind PNA. Mice deficient in iNOS, an enzyme implicated in the promotion of tumorigenesis, were bred into the PyV-mT model. The loss of iNOS did not impact on the number or size of parotid gland hyperplasias, suggesting that NO produced by this enzyme is not a key regulator of PyV-mT-induced parotid gland hyperplasia. The consistent development of parotid hyperplasias in PyV-mT mice and clear identification of these lesions by loss of PNA lectin reactivity provides a useful model for studying early molecular changes in parotid tumorigenesis.

Animals↗