Toshifumi Kurahashi

Expression of the secreted form of clusterin protein in renal cell carcinoma as a predictor of disease extension

To evaluate the significance of clusterin expression in surgically resected renal cell carcinoma (RCC) specimens.

Detection of Micrometastases in Pelvic Lymph Nodes in Patients Undergoing Radical Cystectomy for Focally Invasive Bladder Cancer by Real-time Reverse Transcriptase-PCR for Cytokeratin 19 and Uroplakin II

Purpose: The objective of this study was to clarify the significance of micrometastases in pelvic lymph nodes in patients who underwent radical cystectomy for bladder cancer. Experimental Design: We included 40 patients with locally invasive bladder cancer who underwent radical cystectomy and pelvic lymphadenectomy. Expression of cytokeratin 19 (CK19), uroplakin II (UP II), and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) in 760 lymph nodes were assessed by a fully quantitative real-time reverse transcription-PCR (RT-PCR) assay. The quantification value of CK19 or UP II mRNA was described as each value relative to GAPDH mRNA. In this study, we regarded specimen in which either CK19 or UP II mRNA was positive as “presence of micrometastasis.” Results: Routine pathologic examinations detected tumor cells in 29 lymph nodes from six patients. Real-time RT-PCR identified positive expression of CK19 and UP II mRNAs in 49 lymph nodes from 10 patients and 98 lymph nodes from 16 patients, respectively. Of 633 lymph nodes from 34 patients with no pathologic evidence of nodal involvement, 13 nodes from five patients and 58 nodes from 10 patients were diagnosed as positive for CK19 and UP II mRNAs expression, respectively, by real-time RT-PCR. Presence of micrometastases was significantly associated with other conventional prognostic variables, including pathologic stage and microvascular invasion. Disease recurrence was occurred in eight patients, among whom four patients were negative for lymph node metastasis by routine pathologic examination and diagnosed as having micrometastasis by real-time RT-PCR assay. Furthermore, cause-specific survival rate in patients without micrometastasis was significantly higher than that in those with micrometastasis, irrespective of the presence of pathologic-positive nodes. Conclusions: Approximately 30% of locally invasive bladder cancer shed cancer cells to pelvic lymph nodes, and disease recurrence after radical cystectomy could be explained, at least in part, by micrometastases in pelvic lymph nodes.

Expression of potential molecular markers in prostate cancer: correlation with clinicopathological outcomes in patients undergoing radical prostatectomy.

The objective of this study was to evaluate the expression levels of multiple potential molecular markers in prostate cancer to clarify the significance of these markers as prognostic indicators in patients undergoing radical prostatectomy (RP). This study included a total of 193 patients with clinically organ-confined prostate cancer who underwent RP without any neoadjuvant therapies. Expression levels of 12 proteins, including Ki-67, p53, androgen receptor (AR), matrix metalloproteinase (MMP)-2, MMP-9, vascular endothelial growth factor, Aurora-A, Bcl-2, clusterin, heat shock protein 27 (HSP27), HSP70, and HSP90, in RP specimens obtained from these 193 patients were measured by immunohistochemical staining. Of the 12 molecules, Ki-67, p53, AR, MMP-2, MMP-9, and HSP27 expression were significantly associated with several conventional prognostic factors. Univariate analysis identified these 6 markers as significant predictors for biochemical recurrence as well, while prostate-specific antigen, Gleason score, seminal vesicle invasion (SVI), surgical margin status (SMS), lymph node metastasis, and tumor volume were also significant. Of these significant factors, Ki-67 expression, SVI, and SMS appeared to be independently related to biochemical recurrence by multivariate analysis. Furthermore, there were significant differences in biochemical recurrence-free survival according to positive numbers of these three independent risk factors. These findings suggest that consideration of expression levels of potential molecular markers in RP specimens, in addition to conventional prognostic parameters, would contribute to accurate prediction of biochemical recurrence following RP in patients with clinically localized prostate cancer, and that combined evaluation of Ki-67 expression, SVI, and SMS would be particularly useful for further refinement of the system in predicting biochemical outcome.

Quantitative Detection of Micrometastases in Pelvic Lymph Nodes in Patients with Clinically Localized Prostate Cancer by Real-time Reverse Transcriptase-PCR

Purpose: Routine pathologic examination can miss micrometastatic tumor foci in the lymph nodes of patients with prostate cancer, resulting in confusion during tumor staging and clinical decision-making. The objective of this study was to clarify the significance of micrometastases in pelvic lymph nodes in patients who underwent radical prostatectomy for prostate cancer. Experimental Design: The expression of prostate-specific antigen (PSA) and prostate-specific membrane antigen (PSMA) in 2,215 lymph nodes isolated from 120 patients with clinically localized prostate cancer was assessed by a fully quantitative real-time reverse transcriptase-PCR. We regarded specimens in which either PSA or PSMA mRNAs were positive as proof of the “presence of micrometastasis.” Immunohistochemical staining of lymph node specimens with an antibody against PSA was also done. Results: Pathologic examinations detected tumor cells in 29 lymph nodes from 11 patients, and real-time reverse transcriptase-PCR further identified micrometastasis in 143 lymph nodes from 32 patients with no pathologic evidence of lymph node involvement. The presence of micrometastatic cancer cells was confirmed by immunohistochemical staining in 61 lymph nodes from 17 patients with pathologically negative lymph nodes. The presence of micrometastases was significantly associated with other conventional prognostic variables, including serum PSA value, pathologic stage, Gleason score, and tumor volume. Biochemical recurrence was detected in 32 patients, 17 of whom were negative for lymph node metastasis by pathologic examination (including 4 patients with pathologically organ-confined disease), but were diagnosed as having micrometastasis. Biochemical recurrence–free survival rate in patients without micrometastasis was significantly higher than in those with micrometastasis irrespective of the presence of pathologically positive nodes. Furthermore, only the presence of micrometastasis was independently associated with biochemical recurrence regardless of other factors examined. Conclusions: These findings suggest that ∼30% of clinically localized prostate cancers shed cancer cells to the pelvic lymph nodes, and that biochemical recurrence after radical prostatectomy could be explained, at least in part, by micrometastases in pelvic lymph nodes.

Abnormalities of thyroid function in Japanese patients with metastatic renal cell carcinoma treated with sorafenib: a prospective evaluation.

The objective of this study was to characterize features of thyroid dysfunction in Japanese patients with metastatic renal cell carcinoma (RCC) who were treated with sorafenib. We performed a prospective observational study including 69 Japanese patients who were diagnosed as having metastatic RCC refractory to cytokine therapy and subsequently treated with sorafenib for at least 12 weeks. Thyroid function was assessed before and every 4 weeks after the initiation of sorafenib treatment. Of the 69 patients, 23 (33.3%) did not show any biochemical thyroid abnormality, while the remaining 46 (67.7%) developed hypothyroidism. However, 11 (23.9%) of these 46 hypothyroid patients initially had a suppressed thyroid-stimulating hormone (TSH) value accompanying the increase in free triiodothyronine (T3) and/or free thyroxine (T4) before developing hypothyroidism, suggesting sorafenib-induced thyroiditis. During the observation period of this study, 4 patients (5.8%) demonstrated severe clinical symptoms caused by hypothyroidism and received thyroid hormone replacement. Among several factors examined, only age was significantly associated with the risk for hypothyroidism. These findings suggest that although the incidence of clinically significant hypothyroidism requiring thyroid hormone replacement therapy was not very high, biochemical thyroid abnormality was frequently observed in Japanese RCC patients treated with sorafenib. Accordingly, regular surveillance of thyroid function by the measurement of TSH, free T3, and T4 is warranted during sorafenib treatment in Japanese RCC patients.

Significance of micrometastases in pelvic lymph nodes detected by real-time reverse transcriptase polymerase chain reaction in patients with clinically localized prostate cancer undergoing radical prostatectomy after neoadjuvant hormonal therapy

To clarify the significance of micrometastases in pelvic lymph nodes in patients treated by radical prostatectomy (RP) for prostate cancer after neoadjuvant hormonal therapy (NHT).

Clinical outcome of combined immunotherapy with interferon-α and low-dose interleukine-2 for Japanese patients with metastatic renal cell carcinoma

The objective of this study was to retrospectively investigate clinical outcomes of combined immunotherapy with interferon-alpha (IFN-alpha) and low-dose interleukin-2 (IL-2) in Japanese patients with metastatic renal cell carcinoma (RCC). This study included a total of 52 patients with metastatic RCC who were treated by combined immunotherapy with IFN-alpha and low-dose IL-2 following radical nephrectomy. These patients received a subcutaneous injection of IFN-alpha (5 to 6 million U/d) three times per week and intravenous injection of IL-2 (1.4 million U/d) twice per week. Tumor response was evaluated every 16 weeks, and as a rule, this weekly regimen was repeated 50 times in patients with evidence of objective response or stable disease. In this series, complete response and partial response were achieved in 1 and 11 patients, respectively; however, the remaining 20 and 20 patients were diagnosed as showing stable disease and progressive disease, respectively. Of several parameters examined, presence of metastases at diagnosis and C-reactive protein (CRP) level were significantly associated with response to this combined therapy. The 1-, 3-, and 5-year cancer-specific survival rates of these 52 patients were 80.4%, 51.7%, and 38.8%, respectively. Furthermore, cancer-specific survival was significantly associated with performance status, presence of metastases at diagnosis, metastatic organ and CRP level on univariate analysis; however, only performance status and presence of metastases at diagnosis appeared to be independent predictors of cancer-specific death by multivariate analysis. Toxicities related to this therapy were generally mild and tolerable, limited to World Health Organization (WHO) grade 1 or 2 in the majority of patients. Collectively, these findings suggest that combined immunotherapy with IFN-alpha and low-dose IL-2 could achieve comparatively acceptable oncological outcomes in patients with metastatic RCC; however, other therapeutic options should be considered in patients with unfavorable performance status and/or those positive for metastatic diseases at diagnosis.

Analysis of differences in clinicopathological features between prostate cancers located in the transition and peripheral zones

Background:  The objective of this study was to retrospectively characterize differences in the clinicopathological features of prostate cancer according to the zonal origin.

Improved accuracy for predicting the Gleason score of prostate cancer by increasing the number of transrectal biopsy cores.

Introduction: The objective of this study was to determine whether an increased number of transrectal biopsy cores improves the accuracy of the biopsy Gleason score. Materials and Methods: This study included a total of 225 patients who were diagnosed as having prostate cancer by transrectal needle biopsy and subsequently underwent radical prostatectomy (RP) without neoadjuvant therapy. The rate of grading concordance between biopsy and RP specimens was analyzed by dividing these patients into 2 groups as follows: group A, 107 patients who underwent transrectal biopsy sampling of 9 cores or less (median 8 cores), and group B, 118 patients who underwent biopsy sampling of 10 cores or more (median 12 cores). Results: Concordance between the biopsy and RP Gleason scores in group A (53.3%) was significantly lower than that in group B (69.5%). Upgrading of the biopsy Gleason score in group A (38.3%) was significantly more frequent than that in group B (21.2%). Furthermore, these findings tended to be more prominent as the biopsy Gleason score was lower. Multivariate analysis identified the number of biopsy cores and percent of positive biopsy cores as independent predictors of accurate Gleason grading regardless of other parameters examined in this study. Conclusion: These findings suggest that obtaining a greater number of biopsy cores contributes to improving the accuracy of the biopsy Gleason score for predicting the RP Gleason score; therefore, extended sampling of biopsy cores could provide optimal guidance to determine the therapeutic options in patients with prostate cancer.

Serum Level of Clusterin and Its Density in Men with Prostate Cancer as Novel Biomarkers Reflecting Disease Extension

OBJECTIVES To assess whether the serum level of clusterin and its density could be used as novel biomarkers of prostate cancer. METHODS Sera were obtained from 380 patients with prostate cancer and 120 with benign prostatic hyperplasia. Serum clusterin level was measured by a sandwich enzyme immunoassay, and clusterin density, which was determined by dividing the serum clusterin level by the prostate volume, was also calculated. These findings were analyzed with respect to several clinicopathologic factors. RESULTS The mean serum level of clusterin in prostate cancer patients was significantly higher than that in the benign prostatic hyperplasia group. Both the serum clusterin level and clusterin density in prostate cancer patients were significantly associated with major prognostic factors other than biopsy Gleason score. Of the 380 prostate cancer patients, 162 underwent radical prostatectomy and pelvic lymphadenectomy, and 104 and 58 were diagnosed as having organ-confined and extraprostatic diseases, respectively. The clusterin density in patients with organ-confined disease was significantly higher than that in patients with extraprostatic disease; however, there was no significant difference in the serum clusterin level between these 2 groups. Furthermore, biochemical recurrence-free survival in patients with elevated clusterin density was significantly lower than that in patients with normal density. CONCLUSIONS These findings suggest that serum clusterin level and its density could serve as a useful practical adjuncts to conventional parameters for estimating the extension of prostate cancer.