Comparison of two in vivo models for prostate cancer: Orthotopic and intratesticular inoculation of LNCaP or PC-3 cells

BACKGROUND: The critical events in the clinical course of prostate cancer are the occurrence of metastasis and the induction of the hormone-refractory status of the disease. In order to investigate the factors responsible for these events, we need appropriate in vivo models. MATERIALS AND METHODS: Orthotopic and intratesticular models were created by the injection of LNCaP cells or PC-3 cells into the prostate or testis of severe combined immunodeficient mice. RESULTS: LNCaP cells in the intratesticular model showed a higher incidence of tumor formation and lymph node metastasis when compared with those in the orthotopic model, while PC-3 cells were highly tumorigenic and metastastic in both models. A high concentration of androgens might play a role in tumor aggressiveness of LNCaP cells, given that enhanced mRNA expressions of integrin alphaV and vascular endothelial growth factor was induced by dehydrotestosterone administration in vitro. The high expression of metastasis-related genes, including the urokinase plasminogen activator system, metalloproteinases and vascular endothelial growth factor-C, might be attributed to the high metastatic potential in both models. Interestingly, testicular xenografts of LNCaP cells were able to survive on the subcutis back of castrated male mice as well female mice. CONCLUSIONS: Intratesticular models of prostate cancer appear to be suitable for studying the mechanisms of metastasis and for evaluating various treatment strategies.     

Acute hepatitis C transmitted by needlestick accident despite short duration interferon treatment

Hepatitis C virus (HCV) transmission by needlestick accidents involving hospital employees has become an important problem. The present report is of a case of acute hepatitis C that developed after a needlestick injury, despite short duration interferon treatment performed just after the accident in a trial effort to prevent HCV transmission. Nosocomial infection of HCV in medical employees is reviewed, and the current prospects for protecting them from HCV transmission after needlestick accident are discussed.     

Echo-Doppler measurements of portal vein and superior mesenteric artery blood flow in humans: Inter- and intra-observer short-term reproducibility

The reproducibility of echo-Doppler measurements of portal vein and superior mesenteric artery blood flow has not been extensively studied. In the present study, two groups of subjects were examined to test inter- and intra-observer reproducibility. Each study population consisted of 15 non-portal hypertensive and 15 portal hypertensive subjects. With a standardized technique, the cross-sectional area and velocity of blood flow in the portal vein and superior mesenteric artery were recorded in triplicate by skilled operators. The flow volume of each vessel was calculated by multiplying the cross-sectional area by the velocity of blood flow. The measurements were performed in a blind fashion over a 60 min period. The reproducibility of measurements was assessed by calculation of intraclass correlation coefficients and coefficients of variation. The intra-observer intraclass correlation coefficient was 0.77 for portal vein blood flow and 0.84 for superior mesenteric artery blood flow, suggesting good reproducibility. The intra-observer coefficient of variation was 11 and 9%, respectively. In contrast, the interobserver intraclass correlation coefficient was calculated to be 0.49 for portal blood vein blood flow and 0.57 for superior mesenteric artery blood flow, indicating fair reproducibility. In addition, the interobserver coefficients of variation were calculted to be 20 and 18%, respectively. These data suggest that intra-observer reproducibility in echo-Doppler measurements of portal vein and superior mesenteric artery blood flow is acceptable but inter-observer reproducibility is not. Examination by a single operator, rather than multiple operators, is therefore advisable. Even when measurements are performed by a single investigator an approximate variance of 10% in the measurement in a single subject should be expected.     

Double Response of the Ventricle During Transient Entrainment in a Common Atrioventricular Nodal Reentrant Tachycardia

We report a patient with slow-fast atrioventricuiar (AV)nodal reentrant tachycardia, in which double ventricuJar response was demonstrated during rapid pacing at cycle length of 300 msec or less from the high right atrium. The determinants of double ventricular response during transient entrainment in the present case were: (1)a crucial conduction delay in the slow pathway; (2)the collision between the activation via the antegrade fast pathway (antidromically)of the last paced beat and the activation via the antegrade slow pathway (orthodromically)of the previous paced beat, instead of the unidirectional block in the slow pathway; and (3)the enhanced AV nodal conduction over the antegrade fast pathway.     

Variations of transition zone volume and transition zone index after transurethral needle ablation for symptomatic benign prostatic hyperplasia

BACKGROUND: Transurethral needle ablation (TUNA) is less invasive than other therapies for benign prostatic hyperplasia (BPH) and produces coagulative necrosis within selected adenoma lesions. The action mechanism of TUNA is still obscure, even though many early studies have demonstrated good clinical results of TUNA. It is of interest and importance to know how TUNA influences the volume of the intraprostatic region responsible for bladder outlet obstruction in order to elucidate the anatomical action mechanism of TUNA. METHODS: We retrospectively investigated postoperative variations in volumetric parameters of whole prostate volume (PV), transition zone volume (TZV) and transition zone index (TZI = TZV/PV) in 41 patients with symptomatic BPH who were treated with TUNA. The data were analyzed statistically in relation to the preoperative overall severity and postoperative therapeutic efficacy. RESULTS: Both PV and TZV showed a significant decrease at 3 months after TUNA (P < 0.01) as did the symptom score, quality of life (QOL) score and functional variables, and a decreased level of PV and TZV was sustained until 12 months of follow-up when compared to the baseline (P < 0.01 at 6 months, not significant at 12 months). TZI also showed a similar pattern with a significantly decreased level until the postoperative 6th month (P < 0.05 at 6 months, not significant at 12 months). In 'moderate' cases, TZI achieved the minimum value (0.44 +/- 0.13, P < 0.05 compared to the baseline) at 3 months of follow-up, but the level immediately increased, while in 'severe' cases, TZI gradually decreased and achieved the minimum value (0.44 +/- 0.08, P < 0.05 compared to the baseline) at 12 months of follow-up. In the evaluation by postoperative therapeutic efficacy, there were no significant differences in PV, TZV and TZI between 'excellent and good' cases (E/G group) and 'fair and poor/worse' cases (F/P group) at the baseline or 3 months of follow-up. Both of the efficacy groups showed a significant decrease in PV, TZV and TZI at 3 months when compared to the baseline (P < 0.05). The mean decrease in TZI was significantly larger in the E/G group than in the F/P group (0.064 +/- 0.13 vs 0.027 +/- 0.12, P < 0.05). CONCLUSION: Therapeutic efficacy of TUNA did not depend on the baseline value of PV, TZV and TZI, but on variation of a decrease in TZI during follow-up. Moreover, a slow and lasting decrease in TZI seemed to influence durability of the therapeutic efficacy of TUNA, which was clearly observed in 'severe' cases with a larger prostatic volume than in 'moderate' cases.     

Minimal invasiveness and effectivity of subinguinal microscopic varicocelectomy: a comparative study with retroperitoneal high and laparoscopic approaches

AIM: The standard management of varicocele repair is the subject of ongoing controversy. We retrospectively evaluated three surgical methods of varicocele treatment to determine the minimally invasive and most effective procedure. METHODS: We performed 144 varicocelectomies on infertile patients with left clinical varicocele. Of the patients, 50 were treated with retroperitoneal high ligation under lumbar anesthesia, 33 with laparoscopic ligation under general anesthesia, and 61 with subinguinal microscopic ligation under local anesthesia. Operative time, hospital days, and clinical outcomes were compared between these techniques. RESULTS: The operating time and hospitalization period required for subinguinal microscopic ligation was signi fi cantly shorter compared to those for the other procedures. All patients treated with subinguinal microscopic ligation could achieve normal activity as soon as they returned to their rooms. Postoperative complications were observed in fi ve (10.0%) cases treated with high ligation and three (9.1%) laparoscopic cases, but were not observed after the subinguinal procedure. There were six cases (12.0%) of recurrence in the high ligation group and six (6.1%) in the laparoscopic group, but none in the subinguinal group. Sperm density was signi fi cantly improved in all procedures postoperatively, but sperm motility was not improved. The two-year pregnancy rate calculated by the Kaplan-Meier method was 35.8% for high ligation, 40.4% for laparoscopic ligation and 50.9% for subinguinal microscopic ligation, although there were no statistical differences between the three groups. CONCLUSION: We concluded that subinguinal microscopic varicocelectomy could be a minimally invasive procedure compared to the other two techniques and a worthy method for treating male infertility due to clinical varicocele.     

High-dose chemotherapy for male germ cell tumor

Today, 20-30% of male patients with advanced germ cell tumor (GCT) do not have durable, complete remission in spite of cis-platinum (CDDP)-based chemotherapy. High-dose chemotherapy (HDCT) has been tried in CDDP refractory GCT patients. Initially HDCT was performed with autologous bone marrow transplantation in heavily treated patients. However, the clinical outcome was not good and the treatment-related death rate was not ignorable. Therefore, earlier introduction of HDCT with peripheral blood stem cell transplantation was preferable as it renders HDCT more effective and less toxic, and multicycle HDCT is feasible. The durable free rate of recent HDCT for refractory GCT patients is 32-65%. HDCT is also performed as first line chemotherapy for poor prognosis GCT patients. Induction chemotherapy followed by multicycles of HDCT was tried. The durable free rate of recent HDCT as first line chemotherapy is 43-73%. Although previous reports suggest the superiority of HDCT, one recent randomized controlled trial (RCT) failed to show an improvement with one cycle of HDCT followed by three cycles of standard-dose chemotherapy (SDCT) compared with four cycles of SDCT. Ongoing RCT comparing multicycles of HDCT with SDCT for poor prognostic GCT patients will clarify the role of HDCT. Recently, new regimens of HDCT containing paclitaxel have been devised. In this review, the history, current status and future of HDCT for advanced or refractory GCT will be discussed.     

CLINICOPATHOLOGICAL STUDY OF UNSUSPECTED GALLBLADDER CANCER DIAGNOSED AFTER LAPAROSCOPIC CHOLECYSTECTOMY

Background: Laparoscopic cholecystectomy (LC) has become a common treatment for benign gallbladder diseases. However, this method has not been established for gallbladder cancer. Methods: In the present study, we examined the clinicopathlogical features of gallbladder cancer that was diagnosed after LC. Results: The presence of unsuspected gallbladder cancer was found in five out of 498 patients (1.00%). Preoperative diagnoses were gallstone in two, gallstone with adenomyomatosis in one, adenomyomatosis in one and gallbladder polyp in one. During LC, there was no evidence of cancer, but bile leakage occurred in two patients. Histologically, the carcinoma had invaded into the subserosa in four patients and into the mucosa in one patient. An additional operation was performed in three patients. Histological examination revealed no cancer cells in the resected liver and lymph nodes. During the average follow‐up period of 47.5 months, no recurrences were observed. Although one patient died of liver metastasis 33 months later, the other three patients who underwent an additional radical operation, showed no recurrence. Conclusions: It is important to prevent port site recurrence or dissemination during LC, so a careful maneuver is required to avoid perforation of the gallbladder. At the time of bile leakage, it is best to wash around the liver bed fully to prevent recurrences of unsuspected gallbladder cancers. If gallbladder cancer has invaded the subserosa or deeper level histologically, a radical second operation should be performed as soon as possible.