Moriaki Kato

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.

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

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.

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.

Clinical evaluation of urolithiasis in Crohn's disease

Objectives:  To investigate the characteristics of urolithiasis associated with Crohns disease in a Japanese population.

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.

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

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.

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.

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

Abstract 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.

TMPRSS2 Met160Val polymorphism: Significant association with sporadic prostate cancer, but not with latent prostate cancer in Japanese men

To investigate the association between the TMPRSS2 Met160Val polymorphism and the risk of prostate cancer in Japanese men.