Evaluation of flexible ureteroscope with an omni-directional bending tip, using a JOYSTICK unit (URF-Y0016): an ex-vivo study.

PURPOSE: To compare the range of reach of our newly designed omni-directional ureteroscope (URF-Y0016), compared to the commonly used URF-P6, FlexX2s, and LithoVue™ scopes, in the upper, middle, and lower calyces in an ex-vivo pyelocaliceal model. METHODS: We fabricated a three-dimensional pyelocaliceal model of the upper, middle, and lower pole calyces using urethane and acrylic resin. The inner surface of the dome of each calyx was engraved with reference lines along eight directions, set at 10° of latitude from the top to the base of the dome, and at angles of 0-90°, to precisely determine the range of reach of each scope. The main feature of the URF-Y0016 scope is the omni-directional bending of the tip of the flexible ureteroscope, with the control of these four directions integrated into a handgun-type control unit with a joystick. The range of reach within each calyx was measured by four expert surgeons. RESULTS: The URF-Y0016 scope provided a greater range of reach along all directions in the lower pole calyx compared to URF-P6, FlexX2s, and LithoVue™ scopes (p < 0.001), particularly along the anterior-posterior direction in the lower lobe calyx. However, the URF-Y0016 scope did not influence the improvement of reach range in the upper and middle pole calyx compared to URF-P6, FlexX2s, and LithoVue™ scopes (p = 0.08, p = 0.296). CONCLUSION: The novel design of the URF-Y0016 could improve treatment outcomes for calyceal stones in the lower pole in practice.

Use of various combinations of free, complexed and total prostate-specific antigen levels as predictors of the pathologic stage of prostate cancer.

BACKGROUND: The efficacy of various combinations of total, free and complexed prostate-specific antigen (PSA) levels were assessed to predict the pathologic stage of prostate cancer. METHODS: Total PSA (tPSA), free PSA (fPSA) and complexed PSA (cPSA) levels were measured preoperatively in 52 patients with clinical localized prostate cancer who had undergone radical prostatectomy. Pathologic stages were classified as: organ-confined (n = 27); capsular penetration (n = 14); seminal vesicle involvement (n = 8); involvement of the surgical margins (n = 10); and lymph node involvement (n = 3). RESULTS: The fPSA/tPSA and fPSA/cPSA ratios significantly differed between patients with organ-confined disease and non-organ-confined disease (P = 0.035, P = 0.033, respectively) and between those with favorable versus unfavorable pathology (P = 0.001, P = 0.014, respectively), but tPSA, cPSA, fPSA and the cPSA/tPSA ratio did not. Using a fPSA/tPSA cutoff level of 11%, the prediction of organ-confined disease would increase from 52 to 67% and the rate of predicting favorable pathology would increase from 42 to 62%. A fPSA/cPSA cutoff level of 12% would increase the rate of predicting organ-confined disease to 79% and the rate of predicting favorable pathology would increase to 69%. The positive predictive value of the fPSA/cPSA ratio was higher than that of the fPSA/tPSA ratio, although the receiver operating characteristic curve of the fPSA/cPSA ratio was not different from that of the fPSA/tPSA ratio. CONCLUSION: Although there was no predictive difference found between fPSA/tPSA and fPSA/cPSA ratio, both ratios may help predict the pathologic stage of prostate cancer.

[Comparisons of factors affecting voiding disorders between patients with benign prostate hyperplasia and volunteers].

PURPOSE: The prostate size and motivation to visit clinics were investigated in patients with prostate hyperplasia. OBJECTS AND METHODS: One hundred ninety-five patients who had urinary symptoms and visited our outpatient clinic between September 1994 and October 1999 and 268 age-matched volunteers in Mitaka City who underwent a medical examination of the prostate in June 1997 were compared. International Prostate Symptom Score (IPSS), Quality Of Life Score (QOL score), residual urine volume, prostate volume and urinary flow rate were measured. RESULTS: The prostate volume of the volunteers was 20-25 cm3 irrespective of the age. The prostate size of the outpatients was larger than that of the volunteers for every age group. IPSS and QOL score were significantly higher in the outpatients than in the volunteers. Diurnal urinary frequency and sense of residual urine contributed to the discrimination index of the two groups more significantly than the other scores. There was a significant correlation between prostate volume and residual urine volume. The score of weak urinary steam was inversely and significantly correlated with peak urinary flow rate. CONCLUSIONS: There was no age-related enlargement of the prostate gland. The prostate gland was significantly larger in the patients than in the volunteers even in those in their fifties. Urinary frequency and sense of residual urine are important factors for men to seek and receive medical care.

Prognostic value of three molecular forms of prostate-specific antigen ratios in patients with prostate adenocarcinoma.

OBJECTIVES: To investigate whether different molecular forms of prostate-specific antigen (PSA) ratios could provide prognostic information about the stage and grade of prostate cancer. METHODS: Serum specimens were examined from 53 patients who underwent radical prostatectomy for clinically localized prostate cancer and from 94 patients diagnosed as having no evidence of malignancy (total PSA between 4.1 and 20.0 ng/mL). The free/total PSA (fPSA/tPSA) ratio and complexed/total PSA (cPSA/tPSA) ratio in 18 patients with biochemical recurrence were compared with those of patients either without recurrence or with no evidence of malignancy. RESULTS: The fPSA/tPSA and cPSA/tPSA ratios differed significantly (P <0.05) between patients with organ-confined and those with non-organ-confined disease, but the tPSA, cPSA, and fPSA levels did not (P >0.05). The median values of the fPSA/tPSA ratio in patients with recurrence (7.0%) were significantly lower than in the patients without recurrence (8.9%) or those without evidence of malignancy (15.2%) (P = 0.02 and P <0.01, respectively). The median values of the cPSA/tPSA ratio in patients with recurrence (97.4%) were significantly higher than in patients without recurrence (92.9%) or those without evidence of malignancy (86.7%) (P <0.01 and P <0.01, respectively). At the time of recurrence, 6 (33%) of 18 patients expressed higher fPSA/tPSA ratios (15% or greater) and lower cPSA/tPSA ratios (less than 95%). Five (83%) of these 6 patients appeared to have aggressive tumors according to pathologic stage. CONCLUSIONS: The fPSA/tPSA and cPSA/tPSA ratios differed significantly among the three groups. Thus, a subset of tumors appears to be capable of producing high fPSA/tPSA and low cPSA/tPSA ratios at the time of recurrence, and some of these have an aggressive phenotype. Until this latter phenomenon can be adequately explained, use of these ratios for prognostic purposes should be approached cautiously.

[The significance of early detection for prostate cancer in mass screening].

PURPOSE: In Mitaka city, mass screening for prostate cancer was conducted for 3 years from 1995 to 1997. Clinical stages were compared between patients found by screening and those diagnosed at our clinic during the same time. The significance of serum-free prostate specific antigen (PSA) in mass screening for prostate cancer was examined. MATERIAL AND METHODS: A prospective clinical trial was conducted on men aged 50 years or older. The primary examination consisted of taking the international prostate symptom score, quality of life score, PSA (Tandem-R) and digital rectal examination (DRE). If PSA was greater than 4.0 ng./ml and/or if DRE suggested cancer, transrectal ultrasound-guided sextant prostate biopsies were indicated. RESULTS: Of the men screened, 23.2% (320/1375) had serum PSA greater than 4.0 ng./ml. and/or suspicious findings on DRE. Biopsy was performed in 199 of 320 (62.1%). Cancer was detected in 21 (1.5%, 21/1375). Prostate cancer was found in one case among 154 males (0.65%, 1/154) who were screened twice or more. The cancer stage found by screening was significantly earlier than that diagnosed at the outpatient clinic (Wilcoxon's rank-sum test: p = 0.0047). Receiver operating characteristics analysis showed that the optimal free PSA-to-PSA ratio was 12%. Positive predictive value increased from 18% to 50% when free PSA-to-PSA ratio was combined with PSA. CONCLUSION: 1. Cancer detection rate was 1.5% in the mass screening in Mitaka City. 2. Cancer stage found by screening was significantly earlier than that diagnosed at the outpatient clinic. 3. Free PSA determination might eliminate unnecessary biopsies in men with PSA above 4.0 ng./ml with minimal loss of cancer detection.

[Prostate specific antigen: a role of PSA in the diagnosis of prostate cancer].

Early diagnosis of prostate cancer is best achieved using a combination of DRE and PSA as first-line tests to detect signs of prostate cancer. Because DRE and PSA do not always detect the same cancer, the tests are complementary. Among men with elevated PSA who are negative on DRE, the chance of cancer ranges from 12 to 32%. Most men with PSA elevations do not have cancer. This high false-positive rate among men without cancer has led to many approaches to decrease the incidence of false-positive test results, including PSA density, transition zone PSA density, PSA velocity, age-specific PSA reference ranges and percent free PSA.

Comparisons of the various combinations of free, complexed, and total prostate-specific antigen for the detection of prostate cancer.

OBJECTIVES: We compared the ability of three prostate-specific antigen (PSA) ratios - free-to- total PSA ratio (fPSA/tPSA), free-to-complexed PSA ratio (fPSA/cPSA), and complexed-to-total PSA ratio (cPSA/tPSA) - to distinguish prostate cancer from benign prostatic hyperplasia (BPH). METHODS: We tested 258 consecutive patients who underwent transrectal ultrasound-guided prostate needle biopsy because of an abnormal digital rectal examination or a Tandem-R PSA of >4.1 ng/ml. Free PSA (fPSA) and total PSA (tPSA) were measured by Tandem-R assay. alpha(1)-Antichymotrypsin-complexed PSA (cPSA) was measured by Markit-M PSA-ACT assay. RESULTS: Of the 258 patients, 204 had BPH, and 54 had prostate cancer. The specificity at 96% sensitivity for fPSA/tPSA, fPSA/cPSA, and cPSA/tPSA was 23, 25, and 33%, respectively. Of 162 patients with tPSA between 4.1 and 10.0 ng/ml, 132 had BPH and 30 had prostate cancer. The specificity at 96% sensitivity for f/tPSA, f/cPSA and c/tPSA was 32, 44, and 41%, respectively. There was no significant difference in the area under the receiver-operating characteristic curves among fPSA/tPSA, fPSA/cPSA, and cPSA/tPSA in the overall PSA range or in tPSA between 4.1 and 10.0 ng/ml. CONCLUSION: fPSA/tPSA, fPSA/cPSA, and cPSA/tPSA did not differ in their ability to distinguish prostate cancer from BPH.

Value of reverse transcription polymerase chain reaction assay in pathological stage T3N0 prostate cancer.

BACKGROUND: We tested the ability of the nested reverse transcription polymerase chain reaction (RT-PCR) assay to detect signs of biochemical recurrence of prostate cancer in the lymph nodes and peripheral blood of patients with pT3N0 prostate cancer. METHODS: Using lymph nodes and pre- and postoperative peripheral blood dissected from 30 patients with pT3N0 prostate cancer treated by radical prostatectomy, we used RT-PCR for prostate-specific membrane antigen (PSM) and serum prostate-specific antigen (PSA) to determine the presence of prostate cancer. Results of the nested RT-PCR assay were compared with pathological stages and biochemical recurrence. RESULTS: Two of 13 patients with capsular penetration (15%), 6 of 10 patients with invasion of seminal vesicles (60%), and 3 of 7 patients with a positive surgical margin (43%) were RT-PCR-positive for PSM and/or PSA in the lymph nodes. Results of preoperative RT-PCRs of peripheral blood for PSM and for PSA significantly differed between positive and negative results of RT-PCR in lymph nodes (P < 0.001 and P < 0.001, respectively). Results of postoperative RT-PCRs of peripheral blood for PSM and for PSA also significantly different between positive and negative results of RT-PCR in lymph nodes (P = 0.011 and P = 0.001, respectively). Nine of 11 patients with positive nested RT-PCR for PSM and/or PSA in the lymph nodes (82%) experienced biochemical recurrence. Significant difference in Kaplan-Meier recurrence-free actuarial curves was noted between patients who nested positive and negative on RT-PCR in the lymph nodes, pre- and postoperative peripheral blood, biopsy and prostatectomy Gleason score, and preoperative PSA values. In multivariate analysis, biopsy and prostatectomy Gleason score (P = 0.026, P = 0.020, respectively), pre- and postoperative RT-PCR for PSM in peripheral blood (P = 0.030 and P = 0.040, respectively), and RT-PCR for PSM in lymph nodes (P = 0.035) were independent prognostic factors. CONCLUSIONS: Nested RT-PCR assay of the lymph nodes or peripheral blood significantly predicted biochemical recurrence after surgery. It may help identify patients at risk for recurrence and progression of prostate cancer.

Comparative study of pulsed dye laser and pneumatic lithotripters for transurethral ureterolithotripsy.

BACKGROUND: Clinical effectiveness and safety of the Swiss Lithoclast (Lithoclast) and the Candela MDL-2000 (MDL) in the treatment of lower ureteral stone were examined retrospectively. METHODS: Eighty-six stones from 66 patients and 26 stones from 20 patients were treated by Lithoclast and MDL, respectively. RESULTS: The stone-free rate on 3-month follow-up was 97% and 95% for the Lithoclast and MDL, respectively (no significant difference). The operation time was significantly shorter for the Lithoclast than for the MDL (90.2+/-50.2 vs 120.4+/-55.1 min; P<0.05). Postoperative analgesics were required significantly less frequently in Lithoclast (10/66 vs 11/20; P<0.01). Postoperative hospital stay was significantly shorter for Lithoclast (8.7+/-5.1 vs 12.1+/-4.2 days; P<0.01). CONCLUSIONS: Swiss Lithoclast is an effective and less invasive modality for endoscopic treatment of lower ureteral stones.

Comparison of two investigative assays for the complexed prostate-specific antigen in total prostate-specific antigen between 4.1 and 10.0 ng/mL.

OBJECTIVES: To determine the ability of complexed prostate-specific antigen (cPSA) levels to diagnose prostate cancer. METHODS: Between September 1998 and March 1999, cPSA levels in 182 consecutive patients with an abnormal digital rectal examination (DRE) or a total PSA (tPSA; Tandem-R assay) level greater than 4.1 ng/mL were examined. Levels of cPSA were measured by the Markit-M PSA-ACT (alpha(1)-antichymotrypsin) assay (cPSA-MM) and Bayer Immuno 1 complexed PSA assay (cPSA-BI). Free PSA (fPSA) was measured by the Tandem-R free PSA assay. RESULTS: Of the 140 patients with tPSA between 4.1 and 10.0 ng/mL, 116 were histologically confirmed as having benign tissue; the remaining 24 were diagnosed with prostate cancer. To ensure a 92% sensitivity of cancer detection, a cutoff value for the tPSA, cPSA-MM, and cPSA-BI assays of 4.8 ng/mL, 2.7 ng/mL, and 4.6 ng/mL, respectively, was determined. The percentage of negative biopsies prevented at these cutoff (ie, specificity) values was 14%, 23%, and 24%. No significant differences among these three assays were found. At 92% sensitivity, the cutoff value for the fPSA/tPSA, fPSA/cPSA-MM, and fPSA/cPSA-BI ratios was 18%, 27%, and 18%, respectively. The specificity was 35%, 49%, and 51%. No significant differences were found among these three fPSA ratios. Significant differences were noted between tPSA and the fPSA/cPSA-MM ratio and between tPSA and the fPSA/cPSA-BI ratio. No differences were seen among the other PSA parameters. CONCLUSIONS: No difference in the ability of cPSA levels to distinguish prostate cancer and noncancer was observed between cPSA-MM and cPSA-BI or between their fPSA ratios. Only the fPSA/cPSA-MM and fPSA/cPSA-BI ratios provided significantly enhanced diagnostic performance compared with tPSA.

The significance of the free-to-complexed prostate-specific antigen (PSA) ratio in prostate cancer detection in patients with a PSA level of 4.1-10.0 ng/mL.

OBJECTIVE: To compare the ratio of free prostate specific antigen (fPSA), total PSA (tPSA) and complexed PSA (cPSA, measured using a novel immunoassay) with other variables used to detect prostate cancer in patients with intermediate serum PSA levels of 4.1-10.0 ng/mL. PATIENTS AND METHODS: From July 1997 to August 1998, 140 consecutive patients were assessed; all had intermediate serum PSA levels and/or abnormal findings on a digital rectal examination. All patients underwent transrectal ultrasonography (TRUS)-guided biopsy, and the prostate and transition zone volumes were determined by TRUS. Free and tPSA were measured using the Tandem-R assay (Hybritech Corp., San Diego, CA). PSA complexed with alpha1-antichymotrypsin (cPSA) was measured using an appropriate assay. The ability of cPSA, free-to-total PSA ratio (f/tPSA), free-to-complexed PSA ratio (f/cPSA), tPSA density of the whole prostate (PSAD), of the transition zone (tPSATZ), and cPSA density of the whole prostate (cPSAD) and of the transition zone (cPSATZ) to improve the power of PSA in detecting prostate cancer was evaluated using receiver operating characteristic (ROC) curves. Results Of the 140 patients, 126 had histologically confirmed benign disease and 14 had prostate cancer. The cPSA alone had better specificity for detecting prostate cancer than had tPSA alone but the difference was not significant. The area under the ROC curve for f/cPSA was larger than those for all other variables. With a 93% sensitivity for detecting prostate cancer, a f/cPSA threshold of 25% would result in fewer unnecessary biopsies (40% f/cPSA specificity) than with all other PSA variables. The difference in the resolution was significant between f/cPSA and tPSA, cPSA, tPSAD and tPSATZ, but not with f/tPSA, cPSAD or cPSATZ. In patients with a prostate volume of < 30 mL, the cPSATZ showed better specificity for prostate cancer than tPSA alone. CONCLUSION: Measuring the level of cPSA and its derivatives may provide better differentiation of prostate cancer and benign disease than tPSA alone in patients with a tPSA level of 4.1-10.0 ng/mL.

Detection of micrometastatic prostate cancer cells in the lymph nodes by reverse transcriptase polymerase chain reaction is predictive of biochemical recurrence in pathological stage T2 prostate cancer.

PURPOSE: We evaluated whether detecting prostate cancer cells by the nested reverse transcriptase-polymerase chain reaction (RT-PCR) in lymph nodes has predictive value for serum prostate specific antigen (PSA) recurrence in patients undergoing radical prostatectomy. MATERIALS AND METHODS: We assessed the presence of prostate cancer cells by RT-PCR for prostate specific membrane antigen and PSA assay in lymph nodes dissected from 38 patients with localized prostate cancer treated with radical prostatectomy. The results of nested RT-PCR assay were compared with biochemical recurrence. RESULTS: Nested RT-PCR was positive in the lymph nodes of 2 of 18 patients (11%) with stage pT2a and 5 of 20 (25%) with stage pT2b disease. All 7 patients had biochemical recurrence. We noted a significant difference in the Kaplan-Meier recurrence-free actuarial probability curve in those with positive and negative nested RT-PCR results for prostate specific membrane antigen, PSA and prostate specific membrane antigen-PSA in the lymph nodes (p = 3.02x10(-7), 2.23x10(-7) and 3.02x10(-7), respectively). Multivariate analysis of serum PSA, Gleason score and preoperative RT-PCR assay in peripheral blood showed that nested RT-PCR for prostate specific membrane antigen, PSA and prostate specific membrane antigen-PSA in the lymph nodes were independent predictors of recurrence (p = 0.0089, 0.0075 and 0.0089, respectively). CONCLUSIONS: Nested RT-PCR of the lymph nodes may be a useful pretreatment prognostic test for patients undergoing radical prostatectomy. Further research is necessary using a much larger number of patients with a longer followup.

[A case of familial juvenile gouty nephropathy associated with a right renal tumor].

We present a case of familial juvenile gouty nephropathy which was associated with a right renal tumor that was found incidentally. The patient was a 27-year-old woman who initially presented with acute gouty arthritis at the age of twenty years. Her mother and her sister had been attacked with acute gouty arthritis in their early twenties. Progressive deterioration in the renal function was noted in the three family members who had experienced gouty attack. Her mother was maintained on hemodialysis. As image diagnoses could not rule out malignancy in her right renal tumor, in situ non-ischemic enucleation of the right renal tumor using a microwave tissue coagulator(Microtaze) and a renal biopsy were performed. The pathological diagnosis of the renal tumor was tubulopapillary adenoma, and the renal biopsy showed minimal change in the glomeruli and tubules. The post-operative course was uneventful. The serum creatinine and creatinine clearance before and three months after the operation were 2.4 mg/dl and 2.6 mg/dl, 36.7 ml/min and 32.5 ml/min, respectively. The renal biopsy findings that glomerular and tubular changes were minimal and there was no tissue precipitation of uric acid or sodium urate, and the fact that her renal function decreased progressively despite the treatment of hyperuricemia suggested strongly that renal function might have deteriorated due to unknown factors other than hyperuricemia.

Preoperative nested reverse transcription-polymerase chain reaction for prostate specific membrane antigen predicts biochemical recurrence after radical prostatectomy.

OBJECTIVE: To assess the utility of the nested reverse transcription-polymerase chain reaction (RT-PCR) method for measuring prostate specific membrane antigen (PSM) and prostate specific antigen (PSA) in predicting serum PSA recurrence after radical prostatectomy. PATIENTS AND METHODS: Nested RT-PCRs for PSM and PSA were used in 40 patients who subsequently underwent radical prostatectomy. The accuracy of the RT-PCR assays in predicting PSA failure was compared with those for the preoperative serum PSA level, Gleason score and final pathological staging. The patients were monitored using a PSA assay (Tandem-R, Hybritech, San Diego, CA) at 3 weeks after radical prostatectomy and every 2 months thereafter. Biochemical recurrence was defined as a serum PSA level of >/=0.4 ng/mL. RESULTS: Statistical analysis indicated that the nested RT-PCR assay for PSM was the most accurate preoperative predictor of potential surgical failure (PCR-PSM, P<0.001; PCR-PSA, P=0.018; serum PSA level, P=0.149; Gleason score P=0.388, by Fisher's exact probability test). Biochemical recurrence was evaluated in relation to these methods during a mean (range) follow-up of 16.7 (6-35) months. Of the 40 patients, eight (20%, one with organ-confined cancer and seven with extraprostatic extension of cancer) developed biochemical recurrence. The Kaplan-Meier recurrence-free actuarial probability curves differed significantly between patients with positive and those with negative results for the preoperative nested RT-PCR for PSM (P<0.01, generalized Wilcoxon's test). The nested RT-PCR for PSA, preoperative serum PSA value and Gleason score were not significant predictors of biochemical recurrence (P=0.16, 0.12 and 0.24, respectively). CONCLUSIONS: The nested RT-PCR for PSM was the best preoperative predictor of biochemical recurrence among the factors examined.

[Comparison of Tandem-R PSA and Markit-M PA in the diagnosis of prostate cancer].

The Tandem-R PSA (TR) assay was compared with the Markit-M PA (MM) assay in the diagnosis of the prostate cancer. In patients with a serum prostate specific antigen (PSA) level higher than the cut-off values measured by either the TR assay or the MM assay (4.1 ng/ml and 3.7 ng/ml, respectively), or a suspicious digital rectal examination, sextant biopsy of the prostate was performed. Among 227 patients undergoing biopsy, 64 patients were diagnosed as having prostate cancer. There was a significant difference of serum PSA values between patients with and without prostate cancer in either assay. There was no significant difference between the assays with respect to diagnosing according to prostate cancer using receiver operating characteristic analysis. The correlation between TR and MM in 150 men with a serum Tandem-R PSA below 10 ng/ml was Y = 1.12X + 3.745 (R = 0.68, p < 0.001). The correlation coefficient for the relationship between TR and MM was only 0.68, indicating a poor correlation. Four of the 15 patients with MM values below 4.0 ng/ml calculated by transformation from MM to TR values had prostate cancer. This suggested that conversion of MM values to TR values in the low PSA range presents problems.

Prevalence and renal prognosis of diagnosed autosomal dominant polycystic kidney disease in Japan.

UNLABELLED: The prevalence and renal prognosis of diagnosed autosomal dominant polycystic kidney disease (ADPKD) in Japan were estimated. Hospital-based nationwide surveys were conducted in 1995. The number of ADPKD patients who visited hospitals but were not on chronic dialysis was estimated to be 10,000 (95% confidence interval: 8, 200-11,900) and that of ADPKD patients on dialysis was 4,590, yielding a prevalence of ADPKD of 117 per million population at the end of 1994 (95% confidence interval: 102-132). The prevalence increased with age and reached a peak value of 261 per million population at the age group of 55-59 years. The rate of end-stage renal disease among living patients was calculated based on the assumption that the prevalence of ADPKD in the population under the age of 55 years was 261 per million population. The rate of end-stage renal disease increased with the progression of the patients' age, reaching 49% at the age of 65-69 years and declining thereafter. CONCLUSION: The hospital-based prevalence of ADPKD is lower than the autopsy-based prevalence, suggesting that a fairly large number of these patients do not receive medical care in their lifetime. The probability of end-stage renal disease is at most 50% among ADPKD patients who visit a hospital.

Molecular staging of prostate cancer: comparison of nested reverse transcription polymerase chain reaction assay using prostate specific antigen versus prostate specific membrane antigen as primer.

BACKGROUND: We examined the utility for prostate cancer staging of nested reverse transcription polymerase chain reaction (RT-PCR) using either prostate specific antigen (PSA) or prostate specific membrane antigen (PSM) as primer. METHODS: LNCaP cells were used for the in vitro quantification of RT-PCR. RT-PCR was performed on the peripheral blood of 105 control subjects and 63 patients with prostate cancer (32 who eventually underwent radical prostatectomy and 31 with clinical stage D2 cancer). RESULTS: The nested RT-PCR for the PSA and PSM primers was able to detect 1 LNCaP cell per 10(6) leukemia (K562) cells. None of the control subjects was found positive for the presence of prostate cancer cells by nested RT-PCR. In the 32-patient surgery group, the results of nested RT-PCR were significantly correlated with the pathologic stage of the cancer when using PSM primers (P=2.00 x 10(-3) by Kendall's correlation test) but not when using PSA primers (P=0.06). Extraprostatic extension was significantly more closely correlated with positive PSM nested RT-PCR results (P=0.012 by Fisher's exact probability test) than with positive results of PSA, nested RT-PCR, digital rectal examination, CT imaging, level of serum PSA or Gleason score. In the untreated stage D2 patients, the positive result rate of PSM nested RT-PCR was significantly higher than that of PSA nested RT-PCR (P=0.025 by McNemar test). CONCLUSION: Nested RT-PCR using PSM primers appears to predict the prostate cancer stage more accurately than does nested RT-PCR using PSA primers or conventional clinical staging modalities.

Significance of serum free prostate specific antigen in the screening of prostate cancer.

PURPOSE: The significance of serum free prostate specific antigen (PSA) in the screening of prostate cancer was examined. MATERIALS AND METHODS: A prospective clinical trial was conducted on 701 male volunteers 50 years old or older. Serum free PSA was determined and biopsies were performed if PSA was greater than 4 ng./ml. or if digital rectal examination was suspicious for cancer. RESULTS: Of the men 187 (27%) had a PSA of greater than 4 ng./ml. (11%) and/or a suspicious digital rectal examination (19%). Of 116 biopsies performed in the 701 men cancer was detected in 13 (1.9%). PSA detected more tumors (12 of 13, 92%) than digital rectal examination (9, 69%). Receiver operating characteristic analysis showed that the optimal free PSA-to-PSA ratio (free PSA ratio) was 12%. The positive predictive value for cancer according to PSA with free PSA ratio (50%, 10 cancers in 20 biopsies) was significantly greater (p = 0.0473) than that according to PSA alone (24%, 12 cancers in 50 biopsies), which indicated that 30 of 50 biopsies were avoided with only 2 cancers missed when PSA and free PSA were used for biopsy indication. CONCLUSIONS: Free PSA determination might eliminate unnecessary biopsies in men with a PSA of more than 4 ng./ml. with minimal missed cancers.

Significance of free prostate-specific antigen and gamma-seminoprotein in the screening of prostate cancer.

BACKGROUND: Since free prostate-specific antigen (PSA) and gamma-seminoprotein (gamma-SM) recognize similar epitope(s) of PSA, the significance of serum-free PSA and gamma-SM in the early detection of prostate cancer was compared. METHODS: A prospective clinical trial was conducted on 701 male volunteers, age 50 years or older. Free PSA (Tandem-R free PSA, Hybritech) and gamma-SM (gamma-SM, Chugai) levels were determined, and biopsies were performed if the PSA (Tandem-R, Hybritech) level was > 4 ng/ml, or if digital rectal examination (DRE) was suspicious. RESULTS: One hundred and eighty-seven men (27%) had either a PSA level > 4 ng/ml or a suspicious DRE. Of 116 biopsies performed, cancer was detected in 13 (1.9%, 13/701). Receiver-operating characteristic analysis of free PSA to PSA ratio (free PSA ratio, %) and gamma-SM to PSA ratio (gamma-SM ratio), to differentiate normal biopsy findings from cancer, showed that the optimal values were 12% and 0.38, respectively. Positive predictive value for cancer was 24% (12 cancers/50 biopsies) for PSA alone, 42% (8/19) for the combination of PSA and DRE, 45.5% (10/22) for the combination of PSA and gamma-SM ratio, and 50% (10/20) for the combination of PSA and free PSA ratio. Regression analysis showed that gamma-SM highly correlated with free PSA, but that the analytical detection limit of gamma-SM was 1 ng/ml, significantly higher than that of free PSA. CONCLUSIONS: Free PSA determination might effectively eliminate unnecessary biopsies in subjects with PSA > 4 ng/ml, and gamma-SM might provide a complementary index to free PSA, but its validity should be further studied in other settings, such as after radical prostatectomy or during endocrine treatment.