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Ugur Mungan

Publications and source records attributed to Ugur Mungan.

6 recordsLinked to original sources
PubMed2005

Vascular endothelial growth factor expression in untreated and androgen-deprived patients with prostate cancer.

The aim of the study was to investigate immunohistochemically the expression of vascular endothelial growth factor (VEGF) in untreated and androgen-deprived patients with prostate cancer. The study included 20 patients with prostate cancer who had undergone transurethral prostatectomy due to infravesical obstruction. All patients had been receiving androgen deprivation therapy for at least 3 months. Transurethral prostatectomy specimens were examined for VEGF expression after androgen deprivation, and the biopsy samples of the same patients were used for the evaluation of VEGF expression before androgen deprivation. VEGF expression was analyzed using immunohistochemistry. Staining patterns determined by the staining scores were compared before and after treatment. The correlation of VEGF expression with PSA, Gleason score, and the percent change in PSA after treatment was also investigated. Eligible biopsy specimens were available in 15 of the 20 patients, allowing for the evaluation of VEGF expression before treatment. All prostate cancer specimens were positive. VEGF was localized mainly in the cytoplasm or on the membrane of carcinoma cells. Staining was strong in 86.7% of patients before androgen deprivation. Heterogeneous staining (strong in 25%, moderate in 35%, and weak in 40%) was observed after treatment. Staining scores were significantly higher in patients before androgen deprivation and showed a significant decrease after androgen deprivation (p = 0.007). Tumor staining correlated with Gleason score. No significant correlation was determined between VEGF expression and pre-treatment PSA and percent change of PSA after treatment. Immunohistochemical results indicate that VEGF expression is downregulated by androgen deprivation therapy. VEGF may be a potential target for therapeutic intervention in prostate cancer.

Adenocarcinoma↗
PubMed2005

Echo contrast-enhanced power Doppler ultrasonography for assessment of angiogenesis in renal cell carcinoma.

OBJECTIVE: Tumoral growth is an angiogenesis-dependent event. Although there are studies about the importance of histopathologic angiogenesis in various malignancies, the assessment of the angiogenesis by radiologic techniques is not well established. The aim of this study was to investigate the efficacy of echo contrast-enhanced power Doppler ultrasonography (PDUS) in determining the angiogenic status of renal cell carcinoma (RCC). METHODS: Power Doppler ultrasonography was performed before and after intravenous administration of an echo contrast agent in 42 patients with renal masses. Twenty-one of these renal masses were diagnosed as RCC histopathologically, and these 21 patients were reevaluated retrospectively. The color pixel ratios of selected images were calculated as the ratio of the number of pixels showing power Doppler signals to the total number of pixels within the lesion. The results were compared with the histopathologic microvessel density (MVD). RESULTS: A significant correlation was found between color pixel ratio and MVD values in both PDUS techniques. The use of the echo contrast agent improved this correlation and P values (Spearman rho from 0.436 to 0.551; P from .048 to .01). CONCLUSIONS: Color pixel ratio values reflect the MVD in RCC. Therefore, these results suggest that preoperative quantification of angiogenesis can be possible with the help of PDUS in RCC.

Adult↗
PubMed2004

Significance of COX-2 expression in human renal cell carcinoma.

OBJECTIVES: To evaluate the expression of cyclooxygenase-2 (COX-2) and its association with clinicopathologic parameters, and to investigate the relationships between COX-2 expression and inflammation and carcinogenesis in human renal cell carcinoma. COX-2 expression is associated with aggressive clinicopathologic parameters and an unfavorable prognosis in several human malignancies. METHODS: COX-2 expression was examined immunohistochemically in tumor tissues obtained from 71 patients who underwent radical nephrectomy for renal cell carcinoma. The correlation between COX-2 expression and clinicopathologic findings and patient survival was determined. RESULTS: Of 71 tumors, 63.4% were positive for COX-2 expression. Correlation was found between COX-2 expression and various clinicopathologic features, including tumor size, tumor stage, and tumor grade (P = 0.038, P = 0.004, and P = 0.004, respectively). We found no relationship between COX-2 expression and patient survival. However, the immunoreactivity of COX-2 in renal cell carcinoma and peritumoral areas with inflammation was greater than in areas without inflammation. A statistically significant correlation was found between COX-2 expression and the tubules associated with inflammation (P = 0.038). CONCLUSIONS: COX-2 expression in patients with renal cell carcinoma is associated with several clinicopathologic features. COX-2 expression seems to play a role in the inflammation-carcinoma sequence in renal cell carcinoma. Additional research is required to determine the link between carcinogenesis and inflammation in renal cell carcinoma.

Adult↗
PubMed2003

Reproducibility of the 1998 World Health Organization/International Society of Urologic Pathology classification of papillary urothelial neoplasms of the urinary bladder.

OBJECTIVES: This study assessed the diagnostic agreement and intra- and inter-observer reproducibility of the World Health Organization/International Society of Urologic Pathology Consensus Classification of Urothelial Neoplasms (1998 WHO/ISUP classification) and the 1973 WHO classification. METHODS: A teaching set with 5 slides of each papillary neoplasm of low malignant potential, low-grade papillary carcinoma, high-grade papillary carcinoma, and a guideline, as well as a study set of 30 slides containing ten cases of each category, were sent to participants. Six pathologists expert in urological pathology reviewed the 30 slides of non-invasive papillary urothelial tumors in the study set. Diagnostic accuracy and reproducibility were evaluated using intra- and inter-rater techniques (kappa statistic). RESULTS: A moderate to substantial intra- and inter-observer reproducibility was achieved for both the 1998 WHO/ISUP and 1973 WHO classification. The results of the two classification systems were not different statistically ( P>0.05). Reproducibility was lower in low-grade tumors for both classifications. CONCLUSIONS: The new proposed classification system for non-invasive urothelial neoplasms does not increase the reproducibility. There is still a need for uniformity in grading in order to compare the different studies and therapies and to provide more accurate information for management.

Carcinoma, Papillary↗
PubMedDate not supplied

Expression of cathepsin D in bladder carcinoma: correlation with pathological features and serum cystatin C levels.

AIMS AND BACKGROUND: The aim of this study is to evaluate the expression of cathepsin D in primary bladder cancer and to determine its relationship with conventional pathological features and serum cystatin C levels. METHODS: The immunohistochemical cathepsin D expression and staining patterns of epithelial and stromal cells were investigated in 21 patients with primary bladder carcinoma. Serum cystatin C levels were determined by immunoturbidimetry and compared with matched controls. RESULTS: There were 7 papillary neoplasms of low malignant potential, 7 low-grade and 7 high-grade carcinomas. Six tumors were invasive. Statistical analysis showed a significant inverse relationship between cathepsin D expression of the tumor cells and tumor grade and stage (P = 0.018 and P = 0.046, respectively). Serum cystatin C levels of the controls and patients varied between 0.39 mg/L and 1.99 mg/L (P > 0.05). There was no significant relation between cathepsin D expression in tumor tissue and serum cystatin C levels. CONCLUSIONS: Loss of cathepsin D expression in bladder carcinomas may be associated with high-grade and invasive tumors. Thus, increased cathepsin D expression by tumor cells may be related to local tumor invasion at an early stage, but it seems that extracellular cystatin C is not affected by cathepsin D expression of tumor or stromal cells, and cystatin C concentrations are not directly correlated with the progression of primary bladder carcinomas.

Aged↗