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Makoto Ohori

Publications and source records attributed to Makoto Ohori.

8 recordsLinked to original sources
PubMed2003

The addition of interleukin-6 soluble receptor and transforming growth factor beta1 improves a preoperative nomogram for predicting biochemical progression in patients with clinically localized prostate cancer.

PURPOSE: Several preoperative prostate cancer nomograms have been developed that predict risk of progression using pretreatment prostate-specific antigen (PSA) level, clinical stage, and biopsy Gleason grade. We describe the development and performance of a new nomogram. The nomogram adds new markers to the standard clinical predictors that reflect the biologic behavior of prostate cancer: pretreatment plasma levels of interleukin-6 soluble receptor (IL6SR) and transforming growth factor beta1 (TGF-beta1). PATIENTS AND METHODS: Between November 7, 1994 and December 22, 1997, 714 patients with stage cT1c to cT3a prostate cancer and no prior therapy were treated with radical prostatectomy at the Methodist Hospital, Houston TX. Plasma levels of IL6SR and TGF-beta1 were measured in banked preoperative plasma. With these data, a nomogram was developed to predict the probability of PSA progression within 5 years of surgery. The nomogram was validated with bootstrapping to assess its discrimination and calibration performance. RESULTS: In the multivariable Cox model, PSA (P =.004), IL6SR (P <.001), TGF-beta1 (P <.001), primary Gleason grade (P <.002), and secondary Gleason grade (P =.029) were associated with PSA progression, whereas clinical stage (P =.696) was not. The nomogram seemed to be well calibrated and had a bootstrap-corrected area under the receiver operating characteristic curve (ie, concordance index) of 0.83. For comparison, a nomogram that omitted IL6SR and TGF-beta1 achieved a concordance index of only 0.75. CONCLUSION: We found that pretreatment plasma levels of IL6SR and TGF-beta1 improved the ability to predict biochemical progression by a prognostically substantial margin. A nomogram including the pretreatment levels of these molecular markers, along with standard clinical markers, has been developed and internally validated.

Adult↗
PubMed2003

Do impalpable stage T1c prostate cancers visible on ultrasound differ from those not visible?

PURPOSE: We assessed whether the appearance of cancer within the prostate on sonography is associated with different pathological features and/or prognoses compared with nonvisible impalpable cancers defined as stage T1c by the TNM staging system. MATERIALS AND METHODS: We analyzed the clinical and pathological features, and progression rate in 323 patients with clinical stage T1cNX M0 cancer treated with radical prostatectomy between 1983 and 1998. Mean followup was 46.8 months (range 1 to 186). RESULTS: Of 323 impalpable stage T1c cancers 170 (53%) were visible and the remainder was not visible on ultrasound. There were no significant differences in clinical or pathological features of the cancers in these 2 groups. The prostate specific antigen nonprogression rate at 5 years was also similar for patients with impalpable cancer regardless of whether the lesion was or was not revealed by ultrasound (mean +/- SE 87% +/- 6% and 91% +/- 6%, respectively, p = 0.3767). Of the 170 visible cancers 55 patients had a hypoechoic lesion considered highly suspicious for cancer. These cancers were higher grade, more extensive, less likely to be confined to the prostate and the prognosis was significantly worse than that of impalpable cancer whether or not they were visible at a less suspicious level (IV or less, p = 0.011). However, such highly suspicious visible cancers are rarely visualized today. Initial serum prostate specific antigen more accurately predicts the pathological stage of impalpable cancer than transrectal ultrasound results. CONCLUSIONS: Impalpable cancers currently detected have similar pathological features and prognoses whether or not they are visible by ultrasound. Therefore, it is reasonable to categorize impalpable cancers as stage T1c and analyze the response to treatment regardless of the results of ultrasound.

Adult↗
PubMed2002

Bladder neck involvement in pathological stage pT4 radical prostatectomy specimens is not an independent prognostic factor.

PURPOSE: Bladder neck invasion by prostate cancer in radical prostatectomy specimens is uncommon and, thus, its influence on disease recurrence has not been well defined. Consequently the classification of bladder neck invasion in the TNM staging system is controversial. We studied our cohort of patients with stage pT4 disease and bladder neck invasion to clarify the true clinical behavior and prognostic significance of bladder neck invasion in radical prostatectomy specimens. MATERIALS AND METHODS: The study group consisted of 4,090 consecutive patients treated with radical prostatectomy at one of our institutions between 1983 and 2001. Median followup was 53.1 months (range 1 to 189). After excluding from analysis patients treated with neoadjuvant androgen withdrawal or preoperative irradiation 72 of the remaining 2,571 (2.8%) with bladder neck invasion were classified with stage pT4 disease and their specimens were reviewed. Progression-free probability was determined by Kaplan-Meier analysis. Using the Cox proportional hazards model the independent prognostic significance of bladder neck invasion was assessed after controlling for pretreatment prostate specific antigen, final Gleason sum, extracapsular extension, surgical margins status, seminal vesicle invasion and lymph node involvement. RESULTS: Of the 72 patients categorized with stage pT4 disease 14 (19%) had poorly differentiated Gleason sum 8 to 10 cancer, 38 (53%) had established extracapsular extension, 24 (33%) had seminal vesicle invasion and 8 (11%) had lymph node involvement. However, 26 patients (36%) had cancer confined to the prostate and 28 (39%) had negative surgical margins except for the bladder neck site. The mean 5-year progression-free probability plus or minus SD in all stage pT4 cases was 68% +/- 7%, which was better than in cases of seminal vesicle invasion (52% +/- 5%, log rank test p = 0.0156) but worse than in those of extracapsular extension (84% +/- 4.1%). Univariate analysis of the stage pT4 cohort revealed that higher prostatectomy Gleason sum, more extensive extracapsular extension and seminal vesicle invasion were significantly associated with an adverse prognosis. However, in a multivariate model that included all radical prostatectomy cases the finding of bladder neck invasion or stage pT4 disease did not independently predict prostate specific antigen recurrence. CONCLUSIONS: Stage pT4 disease comprises a heterogeneous group of tumors with various pathological features and inconsistent outcomes. Assigning the pT4 stage to cases of microscopic bladder neck invasion provides no independent ability for predicting disease progression after adjusting for other adverse disease features. Due to this and previously reported data the definition of stage pT4 disease should be modified in the next version of the TNM staging system.

Adult↗
PubMed2002

Prostate biopsy techniques and indications: when, where, and how?

Transrectal ultrasound (TRUS) and prostate biopsy have become one of the most common office-based procedures for the practicing urologist. During the past 50 years, the techniques, indications, and pathologic interpretation of prostate biopsies have evolved. The abandonment of blind finger-guided needle biopsies in favor of systematic TRUS-guided biopsies epitomizes much of this change. Similarly, the indications for prostate biopsy have become more refined. In the past, the presence of a prostatic nodule on digital rectal examination (DRE) was the primary indication for biopsy until the introduction of prostatic-specific antigen (PSA) in the 1980s and its widespread use for prostate cancer screening. Abnormalities of PSA or its derivatives now represent the most common indication for prostate biopsy. Although TRUS initially began as a tool to direct needles into various locations within the prostate, today a great deal of information can be obtained from prostate ultrasound for the discerning clinician. As such, TRUS-guided biopsy of the prostate has become an important staging and diagnostic tool for the practicing urologist. Here we review the current techniques and indications as well as pertinent pathologic and staging data obtained through TRUS and prostate biopsy.

Algorithms↗
PubMed2002

Nomograms and instruments for the initial prostate evaluation: the ability to estimate the likelihood of identifying prostate cancer.

As a result of prostate cancer screening programs, approximately 10% of otherwise healthy men will be found to have an elevated prostate-specific antigen (PSA) level and therefore be at risk for harboring prostate cancer. Patients with an elevated PSA level have a wide variation in the risk for having prostate cancer diagnosed by transrectal ultrasound (TRUS)-guided prostate biopsy. To adequately counsel these patients, some form of individualized risk assessment must be given. There are several tables, artificial neural network (ANN) models, and nomograms that are available to stratify an individual patients risk for having prostate cancer diagnosed by a TRUS biopsy, either initially or on subsequent biopsies after a previous negative biopsy. Presently, nomograms are also being developed to predict the risk not only for having prostate cancer but also for clinically significant prostate cancer. The difficulty in calculating this risk for an individual patient is that the multiple competing clinical and pathologic factors have varying degrees of effect on the overall risk. This problem of competing risk factors can be overcome by the use of nomograms or ANNs. This article reviews the available instruments that are available to the urologist to enable prediction of the risk for having prostate cancer diagnosed by TRUS-guided prostate biopsy.

Biopsy↗
PubMed2002

[The 1992 TNM classification of T2 prostate cancer predicts pathologic stage and prognosis better than the revised 1997 classification].

PURPOSE: In the 1997 the TNM staging system for prostate cancer was changed, reclassifying, T2 cancers from 3 groups (T2a, less than one half of one lobe; T2b, one lobe; and T2c, both lobes) to 2 groups (T2a, one lobe; and T2b, both lobes), combining the 1992 T2a and T2b into the 1997 T2a subclassification. We investigated the pathological stage and prognosis of cancers in the 1992 and 1997 subclassification to determine whether this change was warranted. MATERIAL AND METHODS: We studied a consecutive series of 555 patients with clinical stage T2 prostate cancer treated with radical prostatectomy (RP) between 1983 and 1998. We analyzed the clinical, pathological features and PSA non-progression rate after prostatectomy for patients classified according to the 1992 and the 1997 TNM system. Median follow-up was 51.3 months. RESULTS: In the 1992 TNM system T2a tumors were more likely to have a low PSA (5.8 versus 7.2 and 8.1 ng/ml, p = 0.034, p = 0.012), be confined to the prostate (67% versus 45% and 40%, p < 0.001 for both), be poorly differentiated (48% versus 63% and 66%, p = 0.002 for both) and have a low cancer volume (1.22 versus 2.27 and 2.63 cm3, p = 0.005 for both) than T2b and T2c tumors. But there were no significant differences between T2b and T2c. Reflecting these results, the patients with T2a cancer had a significantly better prognosis with 82 +/- 4% PSA non-progression rate at 5 years compared to 68 +/- 4% of patients with T2b and 73 +/- 4% of patients with T2c (p = 0.007, p = 0.048, respectively). In the 1997 TNM system T2a tumors were also different from T2b tumors in terms with the frequency of confined cancer (54% versus 40%, p = 0.006) and cancer volume (1.78 versus 2.63 cm3, p = 0.013). However, the those differences were smaller than those in 1992 system. There were no significant differences between 1997 T2a and T2b cancers in the serum PSA level and the frequency of a poorly differentiated cancer. In fact, the 5-years recurrence-free survival rate for patients with T2a (73 +/- 3%) was identical to that for T2b cancer. In a Cox proportional hazard regression analysis, however, neither the 1992 nor the 1997 TNM staging subclassifications of T2 cancers were independent predictor of PSA non-progression when the age of patient, serum PSA level and biopsy Gleason grade were included in the analysis. CONCLUSION: Since a palpable tumor less than half of one lobe (1992 T2a) has a distinctly different pathological and prognostic significance compared to T2b and T2c cancers, the T2a subclassification should be retained in future revisions of TNM staging system. However, because the digital rectal examination provides limited information, both PSA results and histological grade in a biopsy specimen should be incorporated into future revision of the TNM staging system.

Adult↗
PubMedDate not supplied

Expression of neutral amino acid transporter ASCT2 in human prostate.

The neutral amino acid transporter ASCT2 has been associated with increased metabolism in malignant tumors. Its biological significance in tumor proliferation, progression, and its impact on cancer patients' survival remains largely unknown. Tissue microarray (TMA) technology was used to build arrays from 640 cases of radical prostatectomies (triplicate normal prostate, benign prostatic hyperplasia (BPH), and prostate adenocarcinoma (PCa)). Slides were immunostained with an antibody to ASCT2 and scored using a 0-3+ semi-quantitation scoring system for both intensity and percentage. Correlation of ASCT2 expression with patients' clinical and pathological variables was analyzed by the Spearman correlation test. Kaplan-Meier analysis and log rank test were used to determine the probability of disease recurrence. Cox regression model was also used for multivariate analysis. 497 PCa had accessible data. ASCT2 was localized in the cytoplasm of epithelial cells of normal prostate, BPH and PCa. High-level expression of ASCT2 was significantly higher in normal tissues (49%) as compared to BPH (25.8%) or cancer (25.3%) (p < 0.001). ASCT2 expression was weakly but significantly correlated with preoperative PSA (Pre-PSA), Gleason score (GS), lymph node status (LN) (p = 0.019). ASCT2 expression was significantly associated with shorter time to biochemical recurrence only on univariate analysis (p = 0.046). ASCT2 appears to be required for the glutamine metabolism in both nonmalignant and malignant prostate. ASCT2-positive PCa seems to be related to a more aggressive biological behavior. ASCT 2 seems to be involved in tumor progression.

Amino Acid Transport System ASC↗