Potential predictive factors of positive prostate biopsy in the Japanese population.

INTRODUCTION: There are numerous arguments for the predictive factors of positive prostate biopsies, differing according to race and region. This study aimed to determine predictive factors for a positive prostate biopsy in East Asian, especially Japanese men, using clinical, laboratory, and transrectal ultrasound (TRUS) findings. METHODS: Data were collected from 466 men who underwent a prostate biopsy for suspected prostate cancer. Variables analyzed including age, digital rectal examination (DRE) findings, prostate-specific antigen (PSA) level, PSA density, prostate volume, and TRUS findings. Logistic regression analysis and the Mann-Whitney U test were used for this study. RESULTS: Logistic regression analysis showed that significant predictors for a positive prostate biopsy for all patients were positive DRE results, prostate volume, and hypoechoic lesions on TRUS. Especially in the patients with PSA levels <10 ng/ml, the significant predictor for positive biopsy was prostate volume. The Mann-Whitney U test showed that significant predictors for a positive prostate biopsy in all patients were PSA density >0.15, positive DRE results, and prostate volume <25 cm(3). Especially in patients with PSA levels <10 ng/ml, significant predictors for a positive prostate biopsy were prostate volume <25 cm(3) and PSA density >0.15. Additionally, even if the data were confined to those patients with seven or more core biopsies, all the predictive factors shown in all patients were significant predictors in this category. CONCLUSION: This study investigated potential predictors for positive prostate biopsy and demonstrated that prostate volume was an independent predictive factor for positive prostate biopsy in patients with PSA levels <10 ng/ml. In the future, we may be able to use our findings to create a nomogram for predicting positive prostate biopsy in Japanese men.

[Inflammatory myofibroblastic tumor of the bladder: a case report].

A 15-year-old girl presented to a clinic with an asymptomatic macrohematuria. Cystoscopy revealed a bladder tumor. The next day she was admitted to our hospital because of preshock status with macrohematuria. Abdominal computed tomography (CT) revealed a solid tumor in the left anterior to lateral wall. Urinary cytology was negative. She received a transfusion and transurethral resection of bladder tumor as an emergent operation. Histopathological examination revealed inflammatory myofibroblastic tumor. Anaplastic lymphoma kinase immunohistopathological studies revealed cytoplasmic staining of the myofibroblasts. To our knowledge, this is the 35th reported case of inflammatory myofibroblastic tumor of the bladder in Japan. She has been followed up for 13 months without any evidence of local recurrence.

Significance of lateral biopsy specimens during transrectal ultrasound-guided prostate biopsies in Japanese men.

OBJECTIVES: Lateral biopsies are thought to have a better cancer detection rate compared with standard sextant biopsies. This study aimed to determine whether lateral peripheral zone biopsies in Japanese men who underwent transrectal ultrasound-guided prostate biopsies provided a significantly higher cancer detection rate than sextant biopsies. METHODS: Between 1999 and 2004, data were collected from 461 men who underwent prostate biopsy and had enough data regarding the performance of lateral biopsies for statistical analysis. There were two categories in this study: (i) patients who underwent sextant prostate biopsies; and (ii) patients who underwent sextant biopsies plus lateral biopsies. RESULTS: Prostate cancer was detected in 141 (30.6%) of 461 patients. It was detected in 24 (22.2%) of 108 patients who underwent sextant biopsies and 117 (33.1%) of 353 patients who underwent sextant plus lateral biopsies. Lateral biopsies were not associated with a statistically higher rate of positive biopsy findings; however, we found a significantly higher ratio of patients with positive findings in those with prostate specific antigen (PSA) levels 10 ng/mL (one of 71, 1.4%) among those who had positive cores only in lateral biopsy samples (P < 0.0001). CONCLUSIONS: Lateral biopsies did not show a significantly higher detection ratio of prostate cancer compared to sextant biopsies. However, lateral biopsies were more effective than sextant biopsies in patients with lower PSA levels. Our findings might be useful for the establishment of biopsy strategies to detect prostate cancer, especially in patients with lower PSA levels.