Kenji Numahata

Sialosyl-Lex expression defines invasive and metastatic properties of bladder carcinoma

Two types of transitional bladder carcinoma have been distinguished based on macroscopic morphology: type A papillary carcinomas, with papillomatous surface outgrowth without infiltration into muscular layer, and type B nodular carcinomas, with a nonpapillomatous surface appearance, most of which display infiltrative growth through muscular layer, and some of which display lymphatic or blood‐borne metastasis. However, there is no specific predictor at early stages for later invasive and metastatic clinical outcome of patients with type B tumors.

RM2 antigen (β1,4‐GalNAc‐disialyl‐Lc4) as a new marker for prostate cancer

Although prostate‐specific antigen (PSA) has been widely used for early detection of prostate cancer, PSA has problems with specificity and prediction of pathological stage. Therefore, a new marker for prostate cancer is urgently required. We examined expression of a novel carbohydrate antigen, β1,4‐GalNAc‐disialyl‐Lc4, defined by the monoclonal antibody RM2, in prostate cancer using 75 cases of radical prostatectomy specimens. RM2 immunoreactivity was negative to weak in all benign glands, and weak to moderate in high‐grade prostatic intraepithelial neoplasia. In prostatic adenocarcinoma, RM2 immunoreactivity was negative to weak (lower expression) in 20 cases, and moderate to strong (higher expression) in 55 cases. A clear difference of RM2 expression level was observed between Gleason patterns 3 and ≥4. Higher expression of RM2 antigen was significantly associated with primary Gleason pattern ≥4, high Gleason score (≥8), larger tumor volume and advanced tumor stage. Furthermore, 5‐year PSA failure‐free survival was significantly lower in the higher expression group. However, no significant relationship was observed between RM2 expression level and preoperative serum PSA. Western blot analysis in prostate cancer cell lines PC3 and LNCap revealed that major 49‐kDa and minor 39‐kDa glycoproteins were common to both cells, but there was an increase of 59‐ and 125‐kDa glycoproteins unique to LNCap and an increase of 88‐ and 98‐kDa glycoproteins unique to PC3. RM2 antigen is a new histological marker for prostate cancer that may reflect the Gleason grading system. Identification of the glycoproteins carrying the RM2 antigen will provide new insights into the properties of prostate cancer.

Lack of Selectin-Dependent Adhesion in Prostate Cancer Cells Expressing Sialyl Lex

Background Recently, it has been reported that upregulation of the oligosaccharide sialyl Lex (SLex) in prostate cancer is associated with hormone‐resistant, aggressive disease. However, it is not clear that SLex expressed on prostate cancer cells has a biological function related to metastatic potential.

The significance of resections for residual masses after chemotherapy in metastatic testicular tumors

Background: After chemotherapy for metastatic testicular tumors, masses may remain, often in the metastatic sites. This study analyses the role of resections for the residual masses.

Impact of unilateral interposition sural nerve graft on the recovery of sexual function after radical prostatectomy in Japanese men: A preliminary study

Purpose:  To determine the effect of an interposition nerve graft on sexual function after radical prostatectomy.

Relevance of postcatheter removal incontinence to postoperative urinary function after radical prostatectomy

Aim: We examined whether postoperative urinary function after radical prostatectomy is associated with immediate incontinence just after catheter removal.

Telomerase activity: Simplification of assay and detection in bladder tumor and urinary exfoliated cells

Detection of telomerase activity can differentiate malignant from benign cells. However, the original telomeric repeat amplification protocol (TRAP) methods had a number of limitations including a radioisotope labeling [α(32)P] dCTP [α(32)P] dGTP system. We developed digoxigenin labeled CX primer to detect telomerase activity without using radioisotope and attempted to detect telomerase activity of bladder tumor and exfoliated cells in bladder cancer patients. Telomerase activity was detected in 5 (71%) of 7 patients diagnosed with grade 1, 31 (97%) of 32 grade 2, and 11 (100%) of 11 grade 3 bladder tumors. In urinary exfoliated cells, 32 (82%) of 39 grades 1 or 2 bladder tumors were positive for telomerase activity but 20 (51%) of 39 were positive for urinary cytology (P < 0.01). Ten (91%) of 11 of grade 3 tumors were positive for telomerase activity and 11 (100%) of 11 were positive urinary cytology. Three of 100 noncancerous patients were positive for telomerase activity. Sensitivity, specificity, and positive predictive value of telomerase activity assay in urinary exfoliated cells were 84%, 97%, and 93%, respectively. Telomerase activity may be a useful diagnostic marker to detect the existence of immortal cancer cells in the urine.

Retroperitoneoscopic Transureteroureterostomy with Cutaneous Ureterostomy to Salvage Failed Ileal Conduit Urinary Diversion

Reconstruction for failed urinary diversion is technically challenging, due to severe tissue adhesion around the anastomotic site. We report successful laparoscopic transureteroureterostomy with cutaneous ureterostomy via a completely extraperitoneal approach to salvage failed ileal conduit in two patients with necrotic ileal conduit and bilateral anastomotic obstruction, respectively. This novel, less invasive approach may offer a viable alternative to open surgical revision for failed ileal conduit urinary diversion.

Efficacy of early ureteral ligation on prevention of intravesical recurrence after radical nephroureterectomy for upper urinary tract urothelial carcinoma: a prospective single-arm multicenter clinical trial

Objective The rate of intravesical recurrence after radical nephroureterectomy for upper urinary tract urothelial carcinoma is high. Seeding upper urinary tract urothelial carcinoma cells onto the damaged bladder wall is considered to be one of the causes of intravesical recurrence after radical nephroureterectomy. We evaluated the utility of early ureteral ligation in preventing the intravesical recurrence. Methods This prospective single-arm clinical trial included patients who underwent radical nephroureterectomy for upper urinary tract urothelial carcinoma in the Tohoku Urological Evidence-Based Medicine Study Group between 2012 and 2013. Early ureteral ligation was defined as ligation of the ureter as quickly as possible after expanding the retroperitoneal space. A historical control was extracted from 454 patients who underwent radical nephroureterectomy in the same group, using propensity score-matched analysis. Intravesical recurrence-free survival rates were analyzed using Kaplan-Meier curves. Factors predicting intravesical recurrence were assessed using multivariate analyses. Results Seventy-four patients underwent early ureteral ligation. Seventeen (23%) patients had intravesical recurrence with a median follow-up period of 24 months. The 1- and 2-year intravesical recurrence-free survival rates in the early ureteral ligation group were 81% and 76%, and in the control group 75% and 63%, respectively (P = 0.160). In patients with renal pelvic cancer, the 1- and 2-year intravesical recurrence-free survival rates in the early ureteral ligation group were 89% and 86%, but in the control group 74% and 64%, respectively (P = 0.025). However, intravesical recurrence-free survival rates were similar in patients with ureteral cancer. Multivariate analyses of a subset of patients with renal pelvic cancer identified early ureteral ligation as an independent predictor of intravesical recurrence. Conclusions Early ureteral ligation decreases the rate of intravesical recurrence after radical nephroureterectomy in patients with renal pelvic cancer. Thus, early ureteral ligation might help in prevention of intravesical recurrence for renal pelvic cancer.

Treatment sequence in castration-resistant prostate cancer: A retrospective study in the new anti-androgen era

In recent years, abiraterone acetate (AA) and enzalutamide (EZL) have become available for the treatment of cancer. Prior clinical trials have demonstrated the benefits of these agents in males with castration-resistant prostate cancer (CRPC). The optimal sequencing of available therapies in the context of efficacy and known cross-resistance remains uncertain. Based on the mechanisms of action and accessible clinical data, AA and EZL may be indicated for the early stages of prostate cancer. Until clinical trials are conducted to determine the best treatment sequence, individualized therapy is required for each patient based on the clinicopathological characteristics. In the present study, 46 sequential patients (median age: 77, range 59-89; median serum PSA level: 56 ng/ml, range 1.5-3,211) with CRPC treated with EZL (160 mg/day) were retrospectively analyzed between June 2014 and July 2015 at the following institutions: Yamagata Prefectural Central Hospital (Yamagata, Japan); Yamagata Tokushukai Hospital (Yamagata, Japan); Ishinomaki Red Cross Hospital (Ishinomaki, Japan); Kan-etsu Hospital (Tsurugashima, Japan); Niigata Cancer Center Hospital (Niigata, Japan); Sakado Central Hospital (Sakado, Japan). A total of 18 patients were pre-treated with Docetaxel (DOC) and 28 patients were DOC-naïve. Once EZL therapy was initiated, increases in prostate specific antigen (PSA) levels were observed in 3/18 patients (17%) pre-treated with DOC and in 6/20 (30%) who were DOC-naïve. In total, 8/28 DOC-naïve patients were treated with AA without EZL. An increase in the PSA level was observed in only 1/8 (12%) cases following AA treatment in the DOC-naïve group. It was demonstrated that AA had a better efficacy in DOC-naïve patients. The efficacy of EZL was limited in AA-pre-treated patients following DOC administration.