Jiro Uozumi

Laparoscopic Radical Nephroureterectomy: A Multicenter Analysis in Japan

BACKGROUND Laparoscopic nephroureterectomy (LNUx) is prevalent in Japan and throughout the world, but long-term outcome data remain limited. OBJECTIVE To understand the present state of LNUx in Japan, we conducted a multicenter analysis of clinical outcome and long-term cancer control for patients who underwent the procedure. DESIGN, SETTING, AND PARTICIPANTS Between January 1995 and December 2005, 1003 patients with urothelial cancer in the upper urinary tract were treated with LNUx at 51 institutions in Japan, and patient data were collected retrospectively. MEASUREMENTS Patient profiles were gathered and analyzed for survival, intravesical recurrence, and risk factors influencing them. RESULTS AND LIMITATIONS Median operative time was 320 min. Median bleeding volume was 232 ml. Complications occurred in 93 cases (9.3%) intraoperatively and in 107 cases (10.7%) postoperatively. Overall survival rate was 70% at 5 yr. Grade 3, pT3 or pT4, multifocal tumor, lymph-node metastasis, and previous or coexistent bladder tumor were independent risk factors for overall survival. Intravesical recurrence rate was 43% at 5 yr. Intravesical recurrence occurred more frequently in males, in patients with multifocal tumors, in patients with previous or coexistent bladder tumors, and in patients who underwent the hand-assisted approach. CONCLUSIONS Our report represents the largest multicenter analysis of LNUx reported to date. Male sex and the use of the hand-assisted approach were shown for the first time to be risk factors for recurrence-free survival and intravesical recurrence. To further analyze the effectiveness of LNUx, a long-term outcome comparison with risk stratification must be made between LNUx and open nephroureterectomy.

Management of extrinsic malignant ureteral obstruction with urinary diversion

Objective:  The effectiveness of urinary diversion for patients with renal insufficiency due to extrinsic ureteral obstruction was assessed.

Adipose tissue explants and MDCK cells reciprocally regulate their morphogenesis in coculture

Adipokine-producing fatty tissues, composed of preadipocytes, adipocytes, and mesenchymal stem cells, surround the kidney. To study the interaction between renal tubular cells and adipose tissue, we cocultured adipose tissue fragments and MDCK cells. MDCK cells in the coculture showed a taller columnar shape with improved organization of their microvilli and basal lamina than that seen in MDCK cell monoculture. The adipose tissue-induced change in morphology was replicated when we added leptin to MDCK cells cultured alone. Adiponectin abolished the leptin effect. Adipose tissue fragments inhibited MDCK cell division and also the formation of single-stranded DNA, an indicator of apoptosis. The fragments promoted the expression of polarity-associated proteins, including the tight junction molecules, ZO-1, atypical protein kinase C, and Cdc42. Further, the fragments also accelerated the expression of pendrin, the chloride/iodide transporter in the MDCK cells. In turn, MDCK cells decreased the number of preadipocytes and CD44+/CD105+ mesenchymal stem cells in the fragments, and promoted adiponectin production from the fragments. Thus, our study shows that adipose tissue fragments promote the hypertrophy, polarization, and differentiation of MDCK cells by attenuating their growth and apoptosis through opposing endocrine or paracrine effects of leptin and adiponectin. Further, MDCK cells inhibit the regeneration of preadipocytes and mesenchymal stem cells in adipose tissue.

Effects of adipocytes on the proliferation and differentiation of prostate cancer cells in a 3-D culture model.

Objective:  To investigate how the mechanism of adipocyte–prostate cancer cell interaction affects the proliferation and differentiation of prostate cancer cells.

Risk factors of postoperative urinary retention after hip surgery for femoral neck fracture in elderly women.

The aim of the present study was to evaluate risk factors for postoperative urinary retention (POUR) in female patients with femoral neck fractures.

Skeletal-related events in urological cancer patients with bone metastasis: A multicenter study in Japan

Objective:  To investigate the incidence of skeletal‐related events (SRE) in urological cancer patients with bone metastases in Japan.

Magnetic resonance imaging of large chromophobe renal cell carcinomas

PurposeThe objective of this study was to clarify the magnetic resonance imaging (MRI) findings of large chromophobe renal cell carcinomas.Materials and methodsFive patients diagnosed pathologically with chromophobe renal cell carcinoma are included. MRI findings were retrospectively evaluated for the tumor contour, uniformity and hypointensity of the rim of the tumor on T2-weighted images, “microscopic fat,” enhancement degree and pattern on dynamic study, and necrosis in the tumor, among other findings.ResultsThe tumor size ranged from 4.8 to 13.7 cm (mean 7.9 cm). The tumor contour was well defined in four patients. All but one tumor showed a hypointensity rim, and all tumors had a heterogeneous appearance on T2-weighted images. “Microscopic fat” was detected in one case. All tumors demonstrated low enhancement compared to that of the renal cortex. All tumors showed heterogeneous enhancement on postcontrast images. Necrosis was seen in four. Hemorrhage and renal vein thrombosis was seen in one.ConclusionChromophobe renal cell carcinomas of large size tend to have a heterogeneous appearance on postcontrast and T2-weighted images, a well-defined tumor contour with a hypointensity rim on T2-wighted images, and lower enhancement than that of the renal cortex. Tumor necrosis is easily apparent, and “microscopic fat” may be observed.

A study on implantable urination assist systems - development of a bladder compression system

We propose an urination assist system implantable in a patient who has difficulty in urination caused by the neuropathic bladder in order to assist the urination. The proposed system assists the urination by directly pushing the bladder of the patient using shape memory alloys (SMA). Peltier elements are used to control the temperature in the system. The effectiveness of the proposed system is evaluated by experiment with a bladder model.

Non-inferiority of silodosin 4 mg once daily to twice daily for storage symptoms score evaluated by the International Prostate Symptom Score in Japanese patients with benign prostatic hyperplasia: a multicenter, randomized, parallel-group study.

To compare the effect of treatment with silodosin 4 mg once daily versus that of silodosin 4 mg twice daily on storage symptoms in Japanese patients with benign prostatic hyperplasia.

Prostate‐specific antigen assay using whole blood samples spotted on filter paper and its application to mass screening for prostate cancer

Aim:  The disc assay system for prostate‐specific antigen (PSA) is a novel technique using a small amount of whole blood on filter paper. The accuracy of this assay system and its feasibility for use in prostate cancer mass screening were evaluated.