Biomedical subjects

Kuang-Kuo Chen

Publications and source records attributed to Kuang-Kuo Chen.

At least 19 recordsLinked to original sources

PubMed2007

Stress urinary incontinence as the presenting symptom of primary male urethral diverticulum-A case report and literature review.

Primary male urethral diverticulum is quite uncommon. It is even more unusual for urinary incontinence to be a presenting symptom of primary male urethral diverticulum. Herein, we report on a 32-year-old male presenting with urine leakage on coughing or abdominal strain beginning from his early twenties. A congenital type bulbar urethral diverticulum is diagnosed by voiding cystourethrography and cystourethroscopy. Endoscopic unroofing of the diverticulum freed the patient from stress urinary incontinence after the surgery.

Adult↗

PubMed2006

Multifactorial nature of male nocturia.

OBJECTIVES: To conduct a prospective study to determine the causes of nocturia in men. METHODS: The study included 41 male patients (mean age 72.5 years) bothered by nocturia (two or more micturitions per night). Eleven asymptomatic young men (mean age 28.4 years) were enrolled as a control group. All completed a 3-day voiding diary. Daytime and nighttime urine samples were collected to determine osmolality and sodium and potassium levels. Urodynamic studies were performed for all patients with nocturia to evaluate for bladder outlet obstruction using the International Continence Society definition. Polysomnography was performed on selected patients to detect sleep apnea. RESULTS: The average nighttime voiding frequency was 3.9 in the patients with nocturia. Nocturnal polyuria (NP) was found in 34 (82.9%) of 41 patients. In these patients, the nighttime urinary sodium excretion was significantly greater than the daytime excretion, with lower nighttime urine osmolality. In contrast, nighttime and daytime sodium excretion was not significantly different in patients without NP, and greater nighttime urine osmolality was noted in the patients without NP and the control group. Of the 41 patients, 24 (58.5%) had a small nocturnal bladder capacity, with detrusor overactivity in 14 of 24 patients. Eighteen patients (43.9%) had both NP and a small nocturnal bladder capacity. Another 18 patients had bladder outlet obstruction and NP. Two patients had sleep apnea. CONCLUSIONS: Our observations have shown that a significant contributor to male nocturia is NP, which results from a disordered diurnal rhythm of sodium excretion and other unknown factors causing nocturnal urinary dilution. However, male nocturia can also be secondary to a combination of factors. Detailed workup is necessary to elucidate all causes.

Adult↗

PubMed2006

Effect of Epimedium brevicornum Maxim extract on elicitation of penile erection in the rat.

OBJECTIVES: To investigate the effect and mechanism of a Chinese medicine (Epimedium brevicornum Maxim [EbM]) on elicitation of penile erection in the rat. METHODS: Adult male Sprague-Dawley rats were used. The penile intracavernous pressure (ICP) was monitored. Intracavernous administration of different doses (30, 100, 300, 1000, 3000, 6500, and 10,000 microg/0.1 mL) of EbM extract and saline 0.1 mL was done. Intracavernous NG-nitro-L-arginine methyl ester (L-NAME) (120 microg) was administered, followed by EbM extract 300 microg 10 minutes later. EbM extract (20, 10, and 10 microg) was stereotaxically delivered into the intracerebral ventricle, paraventricular nucleus of the hypothalamus, and hippocampus, respectively. RESULTS: After intracavernous administration of 30 or 100 microg EbM extract, no significant change in ICP was noted. All other doses (300 to 10,000 microg) of EbM extract elicited a significant increase in ICP, with the greatest peak at 99.7 +/- 0.3 mm Hg (resting 7.8 +/- 1.0 mm Hg) after application of 6500 microg EbM extract. No change in ICP occurred with administration of L-NAME followed by EbM extract. Furthermore, intracavernous saline or administration of EbM extract into the intracerebral ventricle, paraventricular nucleus of the hypothalamus, or hippocampus was ineffective in inducing a significant change in ICP. CONCLUSIONS: These results suggest that intracavernous administration of EbM extract may elicit penile erection in the rat. Nitric oxide may be involved in this penile erection-inducing effect. No central neural effect of EbM extract may exist in the elicitation of penile erection.

Animals↗

PubMed2006

Correlation between serum prostate specific antigen and prostate volume in Taiwanese men with biopsy proven benign prostatic hyperplasia.

PURPOSE: We studied the correlation between serum prostate specific antigen and the volume of different zones of the prostate in Taiwanese men with biopsy proven benign prostatic hyperplasia. MATERIALS AND METHODS: A total of 233 patients with a mean age of 71.4 years (range 42 to 89), serum prostate specific antigen less than 10 ng/ml and pathologically confirmed benign prostatic hyperplasia were enrolled in this study. Total prostate and transitional zone volumes were measured with transrectal ultrasonography. Peripheral zone volume was determined by subtracting transitional zone volume from total prostate volume. Correlations between patient age, total serum prostate specific antigen and the volume of each prostate zone were analyzed with the Pearson correlation coefficient. A linear regression model was used to determine the relationship between prostate specific antigen and prostate volume. The prostate specific antigen-prostate volume relationship in our patients was compared with published data on white and Japanese men. RESULTS: Age did not significantly correlate with serum prostate specific antigen and prostate volume. Serum prostate specific antigen significantly correlated with the volume of each prostate zone. After log transformation the Pearson correlation coefficient between total prostate specific antigen and the volume of the whole prostate gland, the transitional zone and the peripheral zone were 0.369, 0.377 and 0.272, respectively (p <0.001). Taiwanese men had lower prostate volume per unit prostate specific antigen comparing with white men, while the prostate specific antigen-total prostate volume relationship between Taiwanese and Japanese men was similar. CONCLUSIONS: In Taiwanese men with biopsy proven benign prostatic hyperplasia the volume of each prostate zone has significantly correlates with serum prostate specific antigen. The prostate specific antigen-total prostate volume relationship in Taiwanese men is different from that in white men. However, the prostate specific antigen-total prostate volume relationship between Taiwanese and Japanese men is similar.

Adult↗

PubMed2006

Using stainless steel chopstick for self-performing urethral sounding in preventing recurrence of anterior urethral stricture.

Male urethral stricture is prone to recurrence, ranging from 40% to 80% according to the length of stricture no matter what treatment is introduced. Therefore, it has long been a common challenge for urologists to handle the problem. Sounding or self-dilation has proved to be effective in reducing the recurrence rate significantly. However, a standard equipment set of urethral bougie is too expensive for a patient's own use. On the other hand, the performance of regular outpatient sounding is time-consuming and costly. We present an easy way to perform urethral self-dilation using a stainless steel chopstick, which has proved to be cost effective and satisfactory for patients. From February 2001 to February 2003, 6 patients, with a mean age of 64.6 years (range 47-79), were introduced to this maneuver after a urethrotomy and were taught how to perform self-sounding with a stainless steel chopstick (18 Fr equivalent). The distance of advancement was determined individually by calibrating the location of the stricture. The long-term result of this maneuver was later checked with a telephone questionnaire about urination status in April 2005. The urethral strictures were located at penile in 3 patients, bulbar in 1, and navicular fossa with meatus in 2. The mean period for performing self-dilation was 15.3 weeks (range, 2-52). The mean follow-up period was 41.5 months (range, 26-55). No recurrence of stricture was found.

Aged↗

PubMed2006

Hemolysis in transurethral resection of the prostate using distilled water as the irrigant.

BACKGROUND: To investigate the incidence and time course of hemolysis and its clinical effects following transurethral resection of the prostate (TURP) using distilled water as the irrigant. METHODS: Between March 1996 and April 1997, 39 patients who underwent TURP due to benign prostatic hyperplasia (BPH) were randomly included in this study. The levels of plasma hemoglobin, haptoglobin and serum lactic dehydrogenase (LDH) were checked in all patients before, immediately after, and 24 hours after the operation. Serum creatinine and sodium were also checked in 24 patients starting August 1996. Significant hemolysis was identified as simultaneous elevation of plasma hemoglobin (> 10 g/dL), serum LDH and reduction of plasma haptoglobin after TURP. RESULTS: Among the 39 subjects, hemolysis occurred in 17 (43.6%), whose plasma hemoglobin and serum LDH increased while plasma haptoglobin decreased immediately after operation (p < 0.05), but no significant differences between the data before and 24 hours after the operation were noticed. In the hemolysis group, serum creatinine increased while serum sodium decreased immediately after operation (p < 0.05), but the data before and 24 hours after the operation had no significant differences. There were no changes in serum creatinine and sodium levels after TURP in patients without hemolysis. The weight of the resected prostate was 42.5 +/- 15.5 g in the hemolysis group and 23.3 +/- 8.3 g in the nonhemolysis group, while duration of TURP was 68.9 +/- 19.6 minutes in the hemolysis group and 34.2 +/- 8.4 minutes in the nonhemolysis group. Patients with hemolysis had higher resection weight and longer resection time than those without hemolysis (p < 0.001). CONCLUSION: Using distilled water as an irrigant for TURP might cause hemolysis, especially in patients with larger prostates and longer resection times. It is necessary to carry out every effort to shorten resection time and avoid extravasation during surgery.

Aged↗

PubMed2006

Pan-urethral wart treated with 5-fluorouracil intraurethral instillation.

We evaluated whether or not intraurethral instillation of 5-fluorouracil (5-FU) solution can rapidly, safely, and effectively eradicate intraurethral condyloma acuminata in a human immunodeficiency virus (HIV) carrier. A 43-year-old man presented with the major complaint of difficult micturition and blood dribbling from the urethral meatus for more than 6 months. He was an HIV carrier for more than 10 years and had undergone diathermy for perianal warts. Physical examination showed cauliflower lesions over the orifice of the urethra and frenulum base of the penile prepuce. Urinalysis disclosed pyuria and microscopic hematuria. Cystourethroscopy on the following day showed extensive wart lesions extending from the urethra to the bladder neck. Biopsy of the lesions was compatible with condyloma acuminata. 5-FU solution (500 mg in normal saline 50 mL) urethral instillation with massage at the ventral side of the penile shaft for 20 minutes was given once a week for 7 doses. The urine routine was normal. Management was then prescribed once a month until the lesions became invisible under urethroscopy. After 18 doses of 5-FU solution urethral instillation, no visible wart lesions were noted. He has been asymptomatic with no voiding difficulty for more than 1 year.

Adult↗

PubMed2006

Hardness evaluation of penile prostheses.

AIM: This work investigates the hardness and buckling force of penile prostheses to further understand the rigidity of penile prostheses before and after implantation. METHODS: Evaluated herein are four prosthetic samples (three inflatable, one semi-rigid), five real prostheses (one inflatable, four semi-rigid), and one prosthesis after implantation. The hardness is measured with a Shore Durimeter by pressing the tester's indentor to the surface of the specimen. A volunteer with inflatable prosthesis implantation is evaluated with respect to penile hardness versus various numbers of pumping. The buckling force of the prosthesis is also determined by a push-pull gauge and a specially designed sampling table. RESULTS: Results in this study demonstrate that although the inflatable prosthesis could only be pumped to a certain amount of hardness, hardness and buckling force correlate well with each other. After reaching the hardness limit, prostheses can even be pumped a further few times. However, continuous pumping only puts more tension on the prosthetic material without increasing hardness and could induce mechanical failure of the prosthesis. Results also indicate that the buckling force decreases with increasing length of the semirigid prostheses, and increases when the prosthesis has a larger diameter. CONCLUSION: This mechanical measurement of rigidity in penile prostheses could provide more information to clinicians about the penile prosthesis before surgical implantation, and to patients about prosthesis usage after implantation.

Hardness Tests↗

PubMed2006

Superficial transitional cell carcinoma of the ureteral orifice: higher risk of developing subsequent upper urinary tract tumors.

AIM: Reports specifically addressing transitional cell carcinoma (TCC) of the ureteral orifice are scarce. This paper presents our experiences of such tumors, including the characteristics of the disease and the incidence of subsequent upper urinary tract recurrence. METHODS: This study included 572 new cases of TCC of the urinary bladder diagnosed in our institute during a period of 5 years. Thirty-one (5.4%) patients had superficial tumors involving ureteral orifices. All 31 patients underwent transurethral resection of the bladder tumors, including the involved ureteral orifices. After the surgery, patients received regular follow up with cystourethroscopy, urine cytology and periodic intravenous pyelography (IVP). Ureterorenoscopy was performed in cases of suspicious IVP or urine cytology findings. RESULTS: Thirty-one patients with superficial tumors involving the ureteral orifice were followed up for 5-8 years or until death. The pathological stage was Ta in 16 cases and T1 in 15 cases. Bladder tumor recurrence was noted in three (18.8%) of the pTa patients and in seven (46.7%) of the pT1 patients. Subsequent upper urinary tract tumors developed in four (12.9%) patients between 33 and 67 months (mean: 33.5) after the first transurethral resection. All four cases of upper tract recurrence had pT1 primary bladder tumor, which recurred for 1-3 times (mean 1.8) before upper tract recurrence. None of these patients had ureteral stenting after bladder tumor resection. Three of four patients with upper tract recurrence had single lower ureteral tumor, while the remaining one patient had multiple tumors. Patients with subsequent upper urinary tract tumors underwent nephroureterectomy and bladder cuff excision. One died of the disease; the other three cases were free of the disease after the therapy. CONCLUSIONS: Patients with primary superficial bladder transitional cell carcinoma involving the ureteral orifice have a higher risk of developing subsequent upper urinary tract tumors, particularly for pT1 primary bladder tumors. Frequent and close follow up is recommended.

Aged↗

PubMed2006

Voiding pattern of healthy Taiwanese women.

AIM: Few studies have examined the voiding pattern of healthy females, despite the importance of such research for diagnosing abnormal voiding behavior. This study investigates the voiding behavior of healthy women in Taiwan. METHODS: 68 healthy women, aged 19-66 years and claiming to void normally were enrolled. Twenty-two of the subjects (32.4%) were postmenopausal. Each woman completed a 3-day voiding diary. The diary recorded urine volume, voiding frequency, urine volume per voiding for the whole day (24 h), and urine volume during both daytime and nighttime. Age and various other voiding parameters were correlated, and the voiding patterns were compared between premenopausal and postmenopausal women. RESULTS: All women voided 7.34 +/- 1.63 times daily. Higher age was associated with higher whole day and daytime voiding frequency. Nocturia was not common for the group as a whole, with a mean nocturnal voiding of 0.25 times per night. However, higher age was significantly associated with a higher nighttime voiding frequency. A significantly positive correlation was also observed between age and whole day urine volume. Compared with regularly menstruating women, postmenopausal women had a significantly higher whole day and nighttime voiding frequency. Menopause and age both independently affect voiding parameters after multivariate analysis. CONCLUSIONS: The results of this study provide invaluable baseline data on female voiding behavior. Additionally, this study found that for healthy women, age and menstruation status significantly affect voiding patterns. Analysis of female voiding behavior thus should consider these two factors.

Adolescent↗

PubMed2005

Detrusor mitochondrial lipid peroxidation and superoxide dismutase activity in partial bladder outlet obstruction of rabbits.

OBJECTIVES: Bladder outlet obstruction has shown to damage detrusor mitochondria with impaired detrusor contractility. One likely cause for mitochondrial injury is reactive oxygen species (ROS)-induced damages, including lipid peroxidation injury. We designed this study to examine this hypothesis. MATERIALS AND METHODS: Placing a silicon ring around the bladder neck of male New Zealand rabbits induced bladder outlet obstruction. The bladders were removed 3 (N = 6), 7 (N = 6), and 14 days (N = 8) later. Sham operated animals (N = 6 for each time period) served as the controls. Contractile function of the bladder was assessed by the response of the detrusor strips to bethanechol and field stimulation. Detrusor mitochondrial superoxide dismutase (SOD) activity and mitochondrial content of malondialdehyde (MDA) were determined. Detrusor contents of phosphocreatine and adenine triphosphate (ATP) were assayed. RESULTS: (1) Outlet obstruction induced an increase in the bladder weight and a decrease in the contractile function; (2) mitochondrial SOD activity significantly elevated in every time period of the obstruction, indicating a persistently increased ROS generation; (3) detrusor MDA level increased in 3-day obstruction animals. It returned to the control level in 7- and 14-day groups; (4) phosphocreatine content was significantly reduced in every time period of the obstruction; (5) ATP content was significantly decreased in 3- and 7-day groups; while 14-day obstruction group contained similar level as the sham-operated group. CONCLUSIONS: This study shows that bladder outlet obstruction increases generation of ROS and enhances lipid peroxidation of detrusor mitochondria. The resulted mitochondrial damages might sustain, leading to persistently depressed energy production and impaired detrusor contractility.

Adenosine Triphosphate↗

PubMed2005

Primary urothelial carcinoma of the ureter: 11-year experience in Taipei Veterans General Hospital.

BACKGROUND: Urothelial carcinoma of the upper urinary tract is relatively rare, occurring in 5% of all urothelial tumors. Ureteral urothelial carcinoma is even less common than that of the renal pelvis, accounting for about 25% of all upper urinary tract tumors. The aim of this study was to evaluate the clinical behavior, survival, recurrence and prognostic information of primary ureteral urothelial carcinoma from our 11 years of experience at the Taipei Veterans General Hospital. METHODS: We retrospectively reviewed 111 patients with ureteral urothelial carcinoma who had been treated in our hospital between January 1993 and December 2003. Tumor staging was according to the 2002 AJCC TNM classification and stage groupings. Patients with stage Oa and stage Ois were categorized as stage Oa/is, and patients with pathologic T stage pTa and pTis were categorized as pTa/is for statistical analysis. The Kaplan-Meier method was used for survival analysis. RESULTS: There were 69 males and 42 females, with a mean age of 70.5 +/- 9.4 years at diagnosis. Of the 111 patients, 5 presented with stage Oa/is, 38 with stage I, 23 with stage II, 21 with stage III, and 24 with stage IV. Nephroureterectomy with bladder cuff excision was performed in 78 patients, 12 patients received segmental resection of the ureter, 4 received ureteroscopic laser coagulation, and 17 underwent chemotherapy or radiotherapy or both. Tumors were located on the left side in 53 patients, on the right in 53, and bilaterally in 5. The most frequent initial presenting symptom was gross hematuria (65%). The mean postoperative follow-up period was 49.3 months. Disease recurrence in the nephroureterectomy group occurred in 36 patients (46.2%), with 17 (21.8%) at the urinary bladder, 2 (2.6%) at the retroperitoneum, 1 (1.3%) at the contralateral ureter, 6 (7.7%) with distant metastases to the lung, bone, distant lymph nodes or liver, and 10 (12.8%) at multiple sites. The 5-year cancer-specific survival rate was 100% for pTa/is, 95.2% for pT1, 69.4% for pT2, and 43.8% for pT3. All 3 pT4 cases died of cancer in a median of 12 months. Significant prognostic factors for cancer-specific survival by univariate analysis were pT (p = 0.00001), stage (p = 0.00001), type of treatment (p = 0.00001) and grade (p = 0.0001). On multivariate analysis, only stage (p = 0.0001) and grade (p = 0.014) were significant for cancer-specific and overall survival. Stage (p = 0.0001), pT (p =0.0001) and grade (p = 0.026) were also significant prognostic factors of recurrence in multivariate analysis. CONCLUSION: Our experience showed that patients with pTa/is and pT1 tumors treated with radical surgery have excellent prognoses. Tumor stage and grade are the only significant prognostic factors for both cancer-specific and overall survival.

Adult↗

PubMed2005

Urothelial carcinoma of the urinary bladder in young adults--clinical experience at Taipei Veterans General Hospital.

BACKGROUND: The clinical behavior and prognosis of bladder cancer in young patients is not well defined. The aim of this study was, therefore, to evaluate the clinical behavior, pathologic characteristics and prognosis of urothelial carcinoma of the urinary bladder in young adults. METHODS: We retrospectively reviewed records from 30 young patients (23 males, 7 females; age < or = 40 years) with urothelial carcinoma of the urinary bladder who had been treated in our hospital between May 1990 and October 2003. Data were analyzed by the Kaplan-Meier method to assess disease recurrence and survival. RESULTS: The mean age at diagnosis was 34.3 +/- 5 years (range, 22-40 years). Fifteen patients presented with pTa, 9 with pT1, 4 with pT2, 1 with pT3, and 1 with pT4. Twenty-six patients (87.2%) had low-grade bladder cancer, and the other 4 had high-grade disease. The most frequent initial presenting symptom was gross hematuria. The mean postoperative follow-up period was 72.8 months (range, 4-149 months). Fifty percent of superficial bladder cancers recurred a mean of 10.7 months (range, 3-68 months) after operation. One patient died from invasive bladder cancer after radical cystectomy, and 1 died from superficial bladder cancer due to tumor progression. The 5-year cancer-specific survival rate was 95.2% for superficial cancer and 83.3% for invasive cancer. The overall survival rate was 93.3%. CONCLUSION: Urothelial carcinoma of the urinary bladder in young adults is usually associated with low grade and low stage. Invasive bladder cancer had no worse a survival rate than superficial bladder cancer.

Adult↗

PubMed2005

Nephrogenic adenoma arising in a renal cortical cyst.

Nephrogenic adenoma is an unusual lesion of the urinary tract first described by Davis in 1949 as a hamartoma. In 1950, Friedman and Kuhlenbeck subsequently characterized the lesion in more detail and named it nephrogenic adenoma. It appears to be a metaplastic response of the urothelium elicited by trauma and chronic irritation and is considered to be benign. A MEDLINE search of the literature from 1960 to the present revealed no previous documentation of a nephrogenic adenoma arising from a renal cortical cyst. Herein, we present such a case arising in a renal cortical cyst.

Adenoma↗

PubMed2005

Correlation between voiding and erectile function in patients with symptomatic benign prostatic hyperplasia.

BACKGROUND: The relationship between lower urinary tract symptoms and male sexual dysfunction remains controversial. In this study, we aimed to evaluate the relationship between voiding and erectile function (EF) using the American Urological Association Symptom Index (AUA-SI) and International Index of EF (IIEF-15) in patients with benign prostatic hyperplasia (BPH). METHODS: From March 2001 to January 2002, 50 men (aged 43-92 years) with symptomatic BPH were enrolled in the study. They completed the AUA-SI and IIEF-15 questionnaires. An additional question about subjective erectile dysfunction (ED) was also evaluated. AUA-SI scores were divided into 3 categories (irritative, obstructive, and total), and IIEF-15 scores were divided into 6 categories (EF, orgasmic function [OF], sexual desire [SD], intercourse satisfaction [IS], overall satisfaction [OS], and total). RESULTS: Irritative, obstructive and total AUA-SI scores were 7.8 +/- 3.7, 8.4 +/- 5.6 and 16.3 +/- 8.2, respectively. Scores in the 6 categories of the IIEF-15 questionnaire were as follows: EF, 12.1 +/- 10.1; OF, 3.7 +/- 3.8; SD, 4.4 +/- 2.0; IS, 4.5 +/- 4.4; OS, 4.4 +/- 2.6; and total, 29.4 +/- 22.2. No obvious correlation was noted between AUA-SI and IIEF-15 scores. Further, no statistical significance was noted, either between AUA-SI and IIEF-15 severity, or between AUA-SI and EF severity. Among 22 patients who self-reported the absence of ED, 17 (77%) had an EF-domain score less than 26. The mean age of patients with, versus those without, ED was significantly greater. CONCLUSION: Voiding and EF, assessed by the AUA-SI and IIEF-15 questionnaires, respectively, are not correlated in patients with BPH.

Adult↗

PubMed2005

Human kallikrein-2 gene polymorphism is associated with the occurrence of prostate cancer.

PURPOSE: Human glandular kallikrein, which is encoded by the human kallikrein-2 (KLK2) gene, is significantly associated with the occurrence of prostate cancer (PCa). We tested the association between a functional C748T polymorphism of the KLK2 gene and the occurrence of PCa. MATERIALS AND METHODS: Peripheral venous blood samples were obtained from 254 patients with PCa and 168 controls with benign prostatic hyperplasia. All control subjects had normal serum prostate specific antigen and proved to be free from malignancy on pathological examination of resected prostatic tissues. Serum prostate specific antigen, testosterone, Gleason score, clinical and pathological stage, tumor and prostate volume of the patients were investigated. The KLK2 gene polymorphism was determined by the polymerase chain reaction based restriction fragment length polymorphism method. RESULTS: The PCa group had a younger mean age +/- SEM (73.0 +/- 0.5 vs 74.7 +/- 0.5 years, p = 0.010) and higher C allele frequency (82.1% vs 74.7%, p = 0.010) than the control group. The frequency of the CC, CT and TT genotypes was 65.7%, 32.7% and 1.6% in patients with PCa, and 56.0%, 37.5% and 6.5%, respectively, in controls (p = 0.010). C allele carriers (CC and CT genotypes) were at significantly higher risk for PCa than TT homozygous subjects (p = 0.002). CC homozygous subjects were at significantly higher risk for PCa than T allele carriers (CT and TT genotypes) (p = 0.043). The PCa subgroup of patients with pathologically proved, localized PCa also had a higher frequency of the C allele (87.5% vs 74.7%, p = 0.026) and CC genotypes (78.7% vs 56.0%, p = 0.019) than controls. CONCLUSIONS: Our results suggest that the C allele of the functional C748T polymorphism of KLK2 may increase the risk of PCa.

Aged↗

PubMed2004

The impact of polymorphism on prostate specific antigen gene on the risk, tumor volume and pathological stage of prostate cancer.

PURPOSE: A single nucleotide polymorphism with adenine (A) to guanine (G) substitution is identified at position -158 in the androgen response elements region of the prostate specific antigen (PSA) gene. We evaluated the relationship between the PSA -158A/G polymorphism and the risk, tumor volume and pathological stage of prostate cancer. MATERIALS AND METHODS: Peripheral venous blood samples were obtained from 122 patients with prostate cancer and 84 controls with benign prostatic hyperplasia. The diagnosis, tumor volume and pathological stage of prostate cancer were all determined according to the pathological reports of transrectal ultrasound guided prostate biopsy, transurethral prostate resection and radical prostatectomy. The PSA -158A/G polymorphism was determined by polymerase chain reaction based restriction fragment length polymorphism methods. RESULTS: Patients with prostate cancer had significantly greater frequencies of the G allele (87.3% vs 77.4%) and GG genotype (78.7% vs 61.9%) than the control group (p = 0.008 and 0.028, respectively). The OR of GG to AG and AA was 2.27 (p = 0.008). In the prostate cancer group the GG genotype was also associated with larger tumor volume (2.34 vs 0.82 ml) and higher pathological stage (organ confined cancer 68.2% vs 31.8% and extracapsular extension 100% vs 0%) than the GA and AA genotypes (p = 0.013 and 0.036, respectively). CONCLUSIONS: The PSA -158A/G polymorphism is associated with prostate cancer. The G allele increases the risk of prostate cancer and the GG genotype is associated with larger tumor volume and higher pathological stage.

Aged↗

PubMed2004

Differentiation of benign prostatic hyperplasia from prostate cancer using prostate specific antigen dynamic profile after transrectal prostate biopsy.

PURPOSE: Serum prostate specific antigen (PSA) level is increased after needle biopsy (Bx) of the prostate. This study tested the hypothesis that the prostate harboring malignant lesions demonstrates less leakage of PSA after prostate biopsy and this phenomenon can be helpful in discriminating benign from cancer diagnosis. MATERIALS AND METHODS: This prospective study was divided into 3 separate phases. Sextant prostate biopsy was done with transrectal ultrasound guidance, and the change and PSA values after biopsy were evaluated. Phases 1 and 2 had 20 and 41 patients, respectively. PSA dynamic profiles were plotted. We defined the most appropriate timing for blood sampling and the cutoff value of the PSA ratio (post-Bx total PSA-to-pre-Bx total PSA) to be applied for further assessment. Phase 3 recruited 97 cases, of which 66 satisfied the end point criteria in which a diagnosis such as malignancy, or 3 successive benign biopsies or benign transurethral resection of prostate was obtained. RESULTS: From phases 1 and 2 the cutoff value for the PSA ratio was 2.0, and the timing of blood sampling was 60 minutes after the biopsy. In phase 3 of those whose PSA ratio was less than 2.0, 92.6% (25) had cancer. For those whose PSA ratio was greater than 2.0, 82.1% (32) were benign. Of the 4 cases with a PSA ratio less than 2.0 and an initial benign biopsy, 3 (75%) were proven to have cancer later. CONCLUSIONS: Evaluating the 1-hour PSA ratio might be helpful for clinicians to select the high risk patients who might have cancer in the prostate. Repeat biopsy should be suggested for cases with a smaller PSA ratio in spite of initial benign results.

Aged↗