A Gorkem Mungan

Publications (2)3.14 Total impact

• Article: Diagnostic value of serum ghrelin levels in prostate cancer.

  N Aydin Mungan, Sasan Eminferzane, A Gorkem Mungan, Cetin Yesilli, Ilker Seckiner, Murat Can, Ferruh Ayoglu, Bulent Akduman
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  ABSTRACT: Expression of recently identified growth hormone-releasing peptide, ghrelin, and its receptor has been demonstrated in prostate cancer (PCA) cell lines. It was also shown that ghrelin has increased cell proliferation in vitro when added to PCA cell lines. The aim of this study was to evaluate the diagnostic value of serum ghrelin levels in detection of PCA. 30 patients with PCA and 50 patients with benign prostate hyperplasia (BPH) were enrolled in the study. The serum ghrelin levels of PCA and BPH patients were compared. The correlations between ghrelin and age groups, body mass index, total prostate-specific antigen (PSA) levels, free/total PSA ratio, Gleason score, and prostate volume were also studied. There were no statistically significant differences between the two groups and parameters mentioned above in terms of serum ghrelin levels (p > 0.05). Although ghrelin has been shown to induce PCA cell proliferation by in vitro studies, its role in the diagnosis of PCA was not demonstrated in our clinical study. Insufficient secretion of ghrelin into serum or the effect of other sources of ghrelin to serum ghrelin levels could be responsible for this discrepancy.
  Urologia Internationalis 01/2008; 80(3):245-8. · 0.99 Impact Factor
• Article: Values for free/total prostate-specific antigen ratio as a function of age: necessity of reference validation in a Turkish population.

  A Gorkem Mungan, Bulent Erol, Bulent Akduman, Gurdal Bozdogan, Sibel Kiran, Cetin Yesilli, N Aydin Mungan
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  ABSTRACT: The aim of this study was to evaluate age-related changes in free/total prostate-specific antigen (f/t PSA) ratio, focusing on the avoidance of unnecessary prostate biopsies. A total of 898 men aged 30-88 years without a history of prostate surgery and disease were enrolled into the study. Serum tPSA, fPSA and f/t PSA ratios were determined for the study population and for different age categories. All males who had suspicious digital rectal examination and tPSA >4 ng/mL underwent transrectal ultrasonography-guided prostate biopsy. Receiver operating characteristic (ROC) curves for each group were generated by plotting the sensitivity vs. 1-specificity for the f/t PSA ratio. The sensitivity and specificity were obtained using different f/t PSA ratio cutoffs for different age groups. Prostate cancer was detected in 63 patients (7%). Age-specific cutoffs were determined according to likelihood ratios at the levels of 10%, 15% and 15% f/t PSA ratio for ages 50-59, 60-69 and >/=70 years, respectively. However, a single cutoff of 10% is recommended across all age ranges (positive likelihood ratio 2.36). ROC curves demonstrated that the area under the curve (AUC) was significant for all patients with initial PSA of 4-10 ng/mL (AUC 0.703-0.796), except for the >/=70-year age group (AUC 0.549). The current study showed that the use of f/t PSA ratio in patients with PSA levels of 4-10 ng/mL should enhance the specificity of PSA screening and decrease the number of unnecessary biopsies. f/t PSA levels may show dissimilarities according to age and ethnicity, so further studies are warranted to identify this relationship.
  Clinical Chemistry and Laboratory Medicine 02/2007; 45(7):912-6. · 2.15 Impact Factor