Makoto Hata

Efficacy of gadolinium-diethylenetriaminepentaacetic acid-enhanced magnetic resonance imaging for differentiation between superficial and muscle-invasive tumor of the bladder: A comparative study with computerized tomography and transurethral ultrasonography

Gadolinium-labeled diethylenetriaminepentaacetic acid (Gd-DTPA)-enhanced magnetic resonance imaging (MRI) was evaluated in an effort to clarify whether MRI could replace or be proved to be superior to computerized tomography (CT) and/or transurethral ultrasonography. A total of 57 bladder cancer patients was evaluated. MRI was performed with a superconducting magnet operating at 1.5 Tesla. The images acquired were multisections, having a fast spin-echo pulse sequence of less than a 14-second breath holding. Serial scans were performed before and immediately after Gd-DTPA venous injection. The findings on different imaging techniques were compared with the histological stagings. A proper diagnosis was made in 42 of 57 cases (73.7%) by Gd-DTPA-enhanced MRI, in 27 of 57 (47.4%) by CT and in 31 of 57 (54.4%) by transurethral ultrasonography when comparing the histological findings. The sensitivity and specificity for differentiating superficial and muscle-invasive tumor of each imaging method were, respectively, 96.2 and 83.3% in Gd-DTPA-enhanced MRI, 96.0 and 58.3% in CT, and 88.0 and 66.7% in transurethral ultrasonography. These data suggest that the staging of bladder cancer by Gd-DTPA-enhanced MRI appears to be superior and more accurate than the staging obtained by CT and transurethral ultrasonography.

Screening of H-ras gene point mutations in 50 cases of bladder carcinoma

Background Mutation converts the H‐ras gene into an activated oncogene in about 10% of human bladder cancers. Codons 12 and 61 are the major “hot spots” for activation. A simple and accurate method to detect point mutations in these codons may be clinically useful for early diagnosis of bladder cancer.

Transplantation of Human Renal Cell Carcinoma to the Nude Mice: As an Intermediate of in Vivo and in Vitro Studies

Five human renal cell carcinomas were transplanted successfully to nude mice fed and grown under a specific pathogen-free condition. The histology of the transplanted tumor tissue was a close reproduction of the original human cancer tissue in situ. The transplanted tumor tissue possessed an abundant supply of blood vessels, which was considered to be of host animal origin. All transplanted tumor cells grew easily when transferred to an in vitro cell culture system from the nude mice. In this latter cell culture system tumor cells demonstrated a growth pattern characteristic of epithelial cells. The electron microscopy of these cells showed some characteristic morphological features that indicated their cytological origin.

Cadmium nephrotoxicity and evacuation from the body in a rat modeled subchronic intoxication

Background: Cadmium (Cd) is an important industrial pollutant, although its mechanism of toxicity has not been completely clarified. We studied Cd‐induced subchronic nephrotoxicity and the cadmium evacuation system in rats and cultured human renal tubular cells.

Myelolipoma of the Adrenal Gland

A case is reported of an adrenal myelolipoma producing a retroperitoneal hematoma. A right suprarenal mass with fatty density was detected by a computerized tomography scan. The mass had irregular vessels on the arteriogram. This is the youngest patient reported among those with surgically removed myelolipoma. There was no endocrine activity.

Laparoscopic heminephrectomy of a horseshoe kidney using microwave coagulator

CASE REPORT A 17-year-old man was referred to our hospital for right flank pain. An excretory urogram revealed no right kidney and malrotation of the left renal collecting system. Abdominal ultrasonography demonstrated a large complex cystic mass in the right renal region which was confirmed on computerized tomography to be a horseshoe kidney with severe hydronephrosis (part A of figure). After discussion of the indication and modes of nephrectomy, the patient and his family agreed to laparoscopic heminephrectomy. Preoperatively a right percutaneous nephrostomy was constructed to reduce the hydronephrosis and facilitate the laparoscopic procedure. Under general anesthesia, the patient was placed in the semilateral position on the left side and the body angle was adjusted as required by rotating the operating table. The camera port was positioned at the umbilicus and 3, 10 mm. ports were placed in the midabdominal, pararectal and anterior axillary lines, respectively. Incision on the white line of Toldt and medial reflection of the ascending colon exposed the partly collapsed right part of the horseshoe kidney. Further dissection displayed the right ureter and the isthmus of the horseshoe kidney. The renal vein and artery were isolated and divided between clips, respectively. The supplying artery of the isthmus was not clearly detected, and so the isthmus was divided after coagulation with a microwave coagulator with 80 W. output (part B of figure). NO additional hemostatic technique was needed for the cut surface. After the right ureter was clipped and divided, the kidney was delivered and wrapped in an endoscopic bag. The

Multivariate Analysis of Flow Cytometric Deoxyribonucleic Acid Parameters and Histological Features for Prognosis of Bladder Cancer Patients

We studied whether flow cytometry provides significant prognosticators beyond the classical histological evaluation in the patient with bladder cancer. A total of 203 patients with untreated bladder cancer was evaluated using fresh bladder tumor specimens. Tumor grading and stage were the histological prognostic parameters. Deoxyribonucleic acid (DNA) index, percentage S-phase cells, percentage G2/M-phase cells and hypertetraploid cell presence were assessed as flow cytometric prognostic parameters. Multivariate survival analysis was performed using Coxs proportional regression model to study statistical individual prognostic values of histological and flow cytometric parameters. Hypertetraploid cell presence was the single most important prognostic factor (p less than 0.01), with tumor grade being nearly as important (p less than 0.01), followed by tetraploidy (p less than 0.01) and tumor stage (p less than 0.05). No other parameters, including the DNA index or cell phase fractions, contributed to the model. These results indicated that combined use of histological and flow cytometric parameters may provide additional information regarding the clinical outcome for bladder cancer patients.

Antiandrogenic effects of spironolactone: hormonal and ultrastructural studies in dogs and men.

A decrease in the level of plasma testosterone and an increase in the level of plasma progesterone were noted after spironolactone had been administered for 20 days in 5 patients with prostatic carcinoma, as well as in 8 male dogs. Electron microscopic observation disclosed myelin-like bodies in the cytoplasm of Leydig and adrenocortical cells in dogs, contributing to a resolution of the mode of antiandrogenic action of spironolactone.

Body mass index for chronic hemodialysis patients: Stable hemodialysis and mortality

Abstract Body mass index (BMI) is used as a reference for weight control programs in the general population and in morbidity and mortality studies in diabetes patients. However, the implications of BMI in chronic hemodialysis patients is unclear. We studied the BMI of chronic hemodialysis patients, focusing on problems encountered during outpatient hemodialysis therapy and on 2‐year mortality. Outpatients with chronic hemodialysis (n = 258; 144 men, 114 women) were divided into four groups: (i) patients with stable hemodialysis; (ii) patients with marked hypotension requiring catecholamine infusion during hemodialysis; (iii) patients with excessive interdialysis weight gain requiring occasional additional hemodialysis; and (iv) patients with troublesome hemodialysis due to other causes. The statistical differences between the average BMI among these groups were evaluated, and were subdivided into sex, age and the duration of hemodialysis history. The 2‐year mortality rates of these patients were also studied according to their BMI. In patients under 60 years of age, those with excessive interdialysis weight gain had statistically larger BMI (23.2; n = 35) compared to patients with good hemodialysis control (20.1; n = 178), regardless of gender and hemodialysis history. The mortality rate was at a minimum at approximately 20 BMI in patients under 60 years of age. However, lower BMI was associated with a greater mortality rate in patients 60 years or over. For chronic hemodialysis patients, the BMI associated with stable hemodialysis and minimum mortality is approximately 20, in those under 60 years of age. The BMI of aged hemodialysis patients should be considered separately in morbidity and mortality studies.

Metastatic malignant ameloblastoma of the kidneys

Ameloblastoma is an uncommon disease in the urological field. The resulting tumors or cysts are of odontogenic epithelial origin, are usually benign in nature and rarely metastasize to distant organs. We describe a case of metastatic ameloblastic carcinoma in both kidneys of a 38‐year‐old Japanese man, who had a history of malignant ameloblastoma and was referred to us for evaluation because of gross hematuria and left flank pain. Computed tomography showed irregular cystic masses in both kidneys. After we confirmed that the primary lesion and the lung metastatic lesion had not recurred, we treated the patient surgically. Approximately 4 months postoperatively the patient suffered a local recurrence of tumors that was very invasive and aggressive. The patient died 2 months later and the autopsy showed local metastasis only, without any metastatic lesion in the lungs or other organs. The present case showed that malignant ameloblastoma is highly aggressive, and in the case of metastases the prognosis is usually extremely poor.