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Biomedical subjects

A Akdaş

Publications and source records attributed to A Akdaş.

At least 37 records · Page 2Linked to original sources

Correlation of transrectal ultrasonography and core biopsies with pathology results in radical prostatectomy specimens.

BACKGROUND: We compared preoperative tumor location, as identified by transrectal ultrasonography (TRUS), and TRUS-guided core biopsies with the final histopathological examination of radical prostatectomy specimens. METHODS: Thirty patients who had radical retropubic prostatectomy after evaluation with TRUS are included in the study. Diagnosis of prostate cancer was established with TRUS-guided systematic (3 cores from base, mid and apex of the peripheral zone, and 1 core from the transition zone of each side of the prostate) and lesion-directed core biopsies in all cases. Each prostate gland was halved for histopathological examination and results are reported in terms of "sides". RESULTS: Histopathological examination of the prostatectomy specimens revealed prostate cancer bilaterally in 29 glands (58 sides) and unilaterally in 1 gland. Preprostatectomy TRUS examinations missed cancer in 29 sides, and core biopsies were negative for cancer in 14 sides. CONCLUSION: This study revealed that 49% of prostate cancer lesions (n = 29 sides) were not recognized on TRUS and 52% of those (n = 15 sides) were diagnosed only by additional systematic biopsies. Furthermore, even with TRUS-guided systematic core biopsies, failure to detect the prostate cancer lesions may be as high as 24% (n = 14 sides).

Biopsy↗

Short-term effect of digital rectal examination on serum prostate-specific antigen levels. A prospective study.

OBJECTIVE: Prostate-specific antigen (PSA) is widely used as a tumor marker in the early detection of prostate cancer. However, its value is limited by several factors such as not being specific for the cancer tissue, diurnal variations of the secretion, and changes in the serum levels observed following rectal manipulations. The effect of digital rectal examination (DRE) on serum PSA levels is still debatable. METHODS: A prospective study is conducted by utilizing the IRMA count (monoclonal) PSA assay in order to determine the effect of DRE on PSA serum levels. A total of 50 men (median age 61, range 42-75 years) who presented to our outpatient clinic for the first time with lower urinary tract outflow obstruction symptoms were included in this study. Further evaluation revealed prostate cancer in 5 patients (10%) and benign prostate hyperplasia in the others. Blood samples were drawn for a PSA assay from all patients prior to and 30 min and 24 h following DRE (PSA 1-3). RESULTS: The mean PSA values prior to and 30 min and 24 h following DRE were 4.09 +/- 0.67 range 0.2-19.47) ng/ml, 4.50 +/- 0.63 (0.15-17.75), and 4.28 +/- 0.68 (0.23-24.12) ng/ml, respectively. The median PSA levels for PSA 1, PSA 2, and PSA 3 were 2.49 +/- 4.74, 3.22 +/- 4.48, and 2.62 +/- 4.82 ng/ml, respectively. Although, there was a statistically significant increase in serum PSA levels 30 min after DRE, the clinical significance of this increase in PSA values with a mean difference of 0.4 ng/ml remains to be clarified. CONCLUSION: Although the effect of DRE on PSA levels does not appear to be clinically significant, in order to prevent any confusion, it may be the best approach to perform DRE after obtaining serum for PSA analysis.

Humans↗

Glutathione S-transferase and multidrug-resistant phenotype in transitional cell carcinoma of the bladder.

OBJECTIVE: To asses the role of expression of resistance phenotypes in treatment failure in patients with invasive transitional cell carcinoma of the urinary bladder, since P-glycoprotein and glutathione S-transferase pi (GST) expression are implicated in resistance to various chemotherapy agents in different tumors. METHODS: Tumor samples from P-glycoprotein and GST-pi were analyzed by immunohistochemistry. RESULTS: P-glycoprotein and GST-pi were found in 35.7 and 42.9% of the samples, respectively. In 21.4% of the samples there was simultaneous expression of both proteins. No significant impact on prediction of tumor behavior was evident on statistical analysis by any one of the protein expressions. CONCLUSION: Drug resistance in transitional cell carcinoma may be through different mechanisms. Although the small sample size of this study precludes firm conclusions, the assessment of P-glycoprotein or GST-pi expression appears to be of little value as a predictor of response to chemotherapy in this group of tumors.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

Evaluation of three different AgNOR counting methods in advanced carcinoma of the prostate.

We applied the silver staining of nucleolar organizer regions (AgNOR) technique to the pretreatment biopsies of 50 cases of advanced prostate cancer. Three different counting methods were utilized in the enumeration of AgNORs. All methods yielded statistically significant differences of mean AgNOR counts of groups defined by high and low WHO, and by Gleason grades. However, there was overlap among groups, and further analysis of counts by grouping of patients according to their stage, response to treatment, and prognosis was not conclusive. Replicate counts were performed in 10 cases. While intraobserver reproducibility was high by all methods, only the second counting method yielded nonsignificant interobserver variability. There was a significant intratumoral heterogeneity of AgNOR scores. Lack of technical standardization, low reproducibility, and lack of correlation with prognosis limit the use of AgNOR counts in advanced carcinoma of the prostate.

Adenocarcinoma↗

Retroperitoneal fibrosis due to malignancy: a case report.

Retroperitoneal fibrosis is idiopathic in two thirds of cases and is found most commonly as an isolated fibrotic plaque centered over the lumbar spine and entrapping one or both ureters. It has been postulated that fibrosis in the idiopathic cases results from a hypersensitivity reaction to antigens leaking into the retroperitoneum from atheromatous plaques in the aorta or common iliac arteries. In the remaining one third of cases, causes include ergot-derivative drugs, retroperitoneal haemorrhage or urine extravasation, and a desmoplastic response to a variety of tumours.

Fatal Outcome↗

Changing patient and stone features for shock wave lithotripsy (SWL) in Turkey.

Shock wave lithotripsy (SWL) has made a revolution in the treatment of urolithiasis. Recent reports suggesting that stone features for SWL have changed during the last years have forced us to compare our initial and last 250 patients treated at our ESWL unit in terms of stone and patient characteristics. We found that the number of ureteric stones and small calyceal stones have increased significantly with time whereas the number of larger stones undergoing SWL has decreased significantly. We believe that this change in stone features is caused by the changing trends in the treatment of stone disease by incorporating other therapeutic options and modifying the SWL indications according to patient characteristics We also believe that prophylactic lithotripsy for asymptomatic calyceal stones still remains to be a debatable issue.

Adolescent↗

Extracorporeal shock wave lithotripsy (ESWL) for urinary tract stones using Dornier MFL 5000, performed by the technician.

As the only lithotripsy centre at a University Hospital in the most crowded city of Turkey, we have a big number of patients with urinary stones. Between April 1990 and August 1993, 2680 sessions of treatment were done to 1257 renal units. Our study reveals that the results obtained by the performance of an experienced technician are just as reliable as those obtained by an experienced urologist.

Lithotripsy↗

Correction of primary and secondary vesicoureteral reflux by subureteric Teflon injection.

Polytetrafluoroethylene (Teflon) has been used for various purposes since 1963 and in urologic practice for the treatment of vesicoureteral reflux (VUR) since the 1980s. In this study we report on our experience with Teflon injection for the treatment of 28 children with primary or secondary reflux. An overall success rate of 91.3% was achieved in the treatment of primary and 66.6% in secondary reflux. With these results we conclude that Teflon injection is a good alternative in the treatment of VUR.

Child↗

Antimicrobial prophylaxis in management of urinary tract stones by extracorporeal shock-wave lithotripsy: is it necessary?

OBJECTIVES: In a prospective randomized study, we evaluated the incidence of urinary tract infections following extracorporeal shock-wave lithotripsy (ESWL) and the necessity of prophylactic antibiotic administration in patients treated with this modality. METHODS: A total of 360 consecutive patients with renal and ureteric stones who had sterile urine before ESWL treatment and did not have any increased risk of infection received either a single dose of 400 mg of ofloxacin or no prophylaxis. Patients were followed by simple urine analysis and urine cultures together, with clinical evaluations. RESULTS: Only 3 patients (0.8%) had positive urine cultures at 1 week after ESWL. Two of these patients were in the antibiotic prophylaxis group. CONCLUSIONS: The incidence of urinary tract infections after ESWL is extremely low, provided that patients have sterile urine before ESWL, and prophylactic antibiotics are not required.

Adult↗

Transrectal ultrasonography versus digitally guided prostate biopsies in patients with palpable lesions on digital rectal examination.

OBJECTIVE: To compare the efficacy of digital and ultrasonographic guidance of biopsies when there is a palpable lesion on the prostate. PATIENTS AND METHODS: Forty patients with a palpable nodule confined to a single lobe of the prostate underwent digitally guided biopsies of this lesion or biopsies directed by transrectal ultrasonography (TRUS) and/or systematic biopsies. RESULTS: According to the histopathological examination, 21 patients were found to have prostate carcinoma (PCa) using TRUS-guided biopsies, whereas digitally guided biopsies revealed PCa in 18 patients but did not detect three cases. In the study group, the prostate of 10 patients had a normal ultrasonographic appearance and two patients had PCa revealed by systematic biopsies. CONCLUSION: We suggest that in the presence of a palpable lesion in the prostate, regardless of TRUS findings, systematic biopsies are mandatory. Present data indicates that digitally guided biopsies are unnecessary as they do not provide additional information over systematic or TRUS-guided biopsies.

Aged↗

Flow cytometric DNA studies and AgNOR counts in patients with transitional cell carcinoma of the bladder.

Flow cytometry appears to be a promising diagnostic method which may influence the therapeutic approach to transitional cell carcinoma (TCC) of the bladder. The number of silver-stained nuclear organizer regions (AgNORs) seems to correlate with the growth fractions of the cells. In this study, we report the results of combined flow cytometric analysis and AgNOR in 37 patients with TCC of the bladder. A positive correlation was observed in the histological grade, stage and growth pattern in relation to the ploidy of tumors. There were statistically significant differences among the mean AgNOR counts of the different groups as defined by DNA content, histological grade, growth pattern and disease outcome. In different stage groups, the AgNOR counts were related both to recurrence and progression. It was concluded that AgNOR counts performed on routine formalin-fixed paraffin sections furnish significant kinetic information. According to our preliminary results AgNOR counts and the DNA content of the tumors should also be measured to decide on more aggressive treatment in some cases.

Adult↗

Social and medical aspects of undescended testes in Turkey.

In this study, 6,381 primary school boys were examined in Turkey in the years 1990 and 1991 and families and medical personnel were questioned about the information they had on undescended testes and their behavior regarding this matter was noted. Undescended testes were found in 91/6,381 pupils (1.43%) Forty-six families (58.7%) were aware of the abnormality. In 36 of these 46 cases (78%), the mother was the first who noticed the problem. Only 3 cases were first diagnosed by medical staff (nurses or doctors). Eighteen cases were diagnosed under 2 years of age, but apparently they had not been managed correctly because of ignorance regarding possible complications. Of the 46 families, who were aware of the problem, only 29 (63%) had seen a physician. In other words, only 31% (29/91) of the boys with undescended testes received medical help. This study has shown that no genital organ examination of the newborn is performed after most deliveries and there is a considerable unawareness of undescended testes both by the families and by medical personnel.

Adolescent↗

Human leukocyte antigen subtype analysis in patients with advanced adenocarcinoma of the prostate.

Human leukocyte antigens (HLA) are cell surface glycoproteins that have a significant role in the immune system. In some cancers, changes in major histocompatibility complex (MHC) class I and II expression, usually a reduction or loss of these molecules, appear to provide a mechanism whereby tumor cells may escape host immunity. HLA analysis in patients with advanced adenocarcinoma of the prostate revealed the antigens with the highest relative risk factors as DRw52, DRw53, Bw73, DR2, and B5(51). As a result, determination of HLA haplotypes may prove to be useful in determining the men with a higher risk of developing prostate cancer.

Adenocarcinoma↗

The role of ureteroscopy as a diagnostic and therapeutic tool in various indications.

Ureteroscopy is now in routine use for the diagnosis and treatment of various pathologies in the upper urinary tract. We report here on our experience in diagnostic and therapeutic applications of the 11.5 F rigid ureteroscope in 85 patients and 88 ureters. An overall success rate of 68.18% (60/88) was achieved when therapeutic and diagnostic interventions were evaluated together. Success rate was 66.65% in the treatment of ureteral stones (all locations), 100% in the removal of retained catheters, and 81.82% in diagnostic interventions. Frequencies of complications like postoperative fever, stone migration, and various degrees of ureteral perforation were 5.68%, 5.68%, and 7.95%, respectively, consistent with current literature. We conclude that rigid ureteroscopy can be safely applied for appropriate indications in the hands of competent urologists.

Adult↗

Ureteral extracorporeal shock wave lithotripsy utilizing Dornier MFL 5000.

Early reports indicated that stones in the upper ureter that have been manipulated back into the kidney have a higher success rate with SWL than those treated in situ. Difficulties in detecting stones in the mid and lower ureter with lithotripters using ultrasonographic localization also limit in situ SWL of ureteral calculi. We treated 254 patients with ureteral calculi (85 upper, 72 mid, and 97 lower) using in situ SWL on the Dornier MFL 5000. The mean stone volume was 1.4 cm2. Approximately one third of the patients required more than one session. The mean number of shock waves was 2010 (range 1400-3000) with a mean voltage of 20 kV (range 14-30 kV). Fragmentation was achieved in 92.6% of the patients. Only 0.4% of the sessions involved general anesthesia. At 3-month follow-up, available in 75% of the patients, the stone-free rate was 82.6%. Ureteral calculi can be treated effectively in situ by means of SWL.

Adolescent↗

Short-term bioeffects of extracorporeal shockwave lithotripsy.

Safety guidelines for shockwave delivery during extracorporeal shockwave lithotripsy (SWL) are not yet clear. Renal functions were assessed by using urinary N-acetyl-beta-D-glucosaminidase (NAG), lactate dehydrogenase (LDH), alanine aminotransferase (ALT; EC.2.6.1.2), aspartate aminotransferase (AST; EC. 2.6.1.1), and gamma-glutamyltransferase (GGT) as well as sodium, potassium, and calcium concentrations in respect to tubular functions after SWL with the Dornier MFL 5000 unit in 32 patients. In order to monitor glomerular function, we determined microalbuminuria. Transient glomerular and tubular damage occurs in SWL-treated kidneys. The minimum interval between two shockwave treatments should be at least 7 days.

Adolescent↗

Impact of prostate-specific antigen density in benign prostatic hyperplasia and prostate carcinoma. Preliminary results.

In an attempt to enhance the success of prostate-specific antigen (PSA) in the diagnosis and staging of prostate carcinoma (PCa) the concept of PSA density (PSAD) has been introduced by Benson et al. Likewise a study to investigate the role of PSAD in 53 patients with PCa and 47 patients with benign prostatic hyperplasia (BPH) has been done. PSADs seemed to increase directly proportional to the grade in PCa and differed significantly between patient groups with BPH and localized+metastatic PCa, BPH and localized PCa, and localized PCa and metastatic PCa. Although 0.6 level for PSAD seemed to be a rational cut-off level in our study, this issue needs to be studied in multiple centers involving an increased number of patients for resolution.

Aged↗

Transurethral grooving of the prostate in the treatment of patients with benign prostatic hyperplasia. An alternative to transurethral incision.

Various alternatives exist for the treatment of bladder outlet obstruction due to benign prostatic hyperplasia (BPH). Incision of the bladder neck and prostate has proved its efficacy in many studies, especially in small prostates. The major drawback of the procedure is inability to obtain tissue specimens to exclude malignancy. We introduced a method to overcome this drawback by incising grooves at 5 and 7 o'clock with standard resection loops which created not only the incisions but also provided enough tissue for pathological examination. Twenty-five patients with BPH underwent transurethral grooving. Pre- and post-operative urodynamic studies revealed significant improvement in both maximum and average flow rates. The re-operation rate in the entire group was 12%. Transitional cell carcinoma of the prostatic urethra was detected in 1 patient, which proved its superiority to standard incision procedures.

Aged↗