Expression of aquaporin 1 in primary renal tumors: a prognostic indicator for clear-cell renal cell carcinoma

Background

Aquaporin 1 (AQP1) is a water channel expressed in many epithelial tissues and endothelium, including the proximal nephron of the kidney.

Objective

We measured AQP1 expression in primary renal cell carcinomas (RCCs) and evaluated its significance and prognostic utility.

Design, setting, and participants

We examined AQP1 expression in 559 sporadic renal tumors as well as in 43 normal kidney tissue samples and collected clinicopathologic and prognostic data.

Measurements

AQP1 expression was measured by using real-time quantitative polymerase chain reaction (PCR).

Results and limitations

All normal kidney samples presented substantial AQP1 expression. Among tumor subtypes, AQP1 expression was significantly higher in clear-cell and papillary RCCs, whereas it was lower in chromophobe RCCs, oncocytomas, and collecting-duct carcinomas. In clear-cell RCC, AQP1 was significantly higher in patients without symptomatic presentation or whose tumors were smaller, lower grade, or either lower stage or lacking in microvascular invasion. Von Hippel-Lindau (VHL) tumor suppressor gene mutational status did not affect expression level. Cox univariate and multivariate analyses strongly associated high AQP1 expression with better prognosis in cancer-specific and cancer-free survival tests in all patient cohorts, as well as in cancer-specific survival in a cohort of patients with advanced metastatic RCC. The time-dependent receiver operation characteristic (ROC) analyses, combined with logistic regression models, revealed that the addition of the AQP1 parameter to the University of California Los Angeles Integrated Staging System (UISS) prognostic score can improve the accuracy of predictions of both cancer death and recurrence for all patient cohorts as well as of cancer death for advanced cases within a 5-yr follow-up period in clear-cell RCC. High AQP1 expression was also associated with better outcome in a univariate cancer-specific survival test in papillary RCCs.

Conclusions

AQP1 shows RCC subtype-specific expression, and its expression level provides useful prognostic information for patients with clear-cell RCC.     

An ultrasonographic classification for diverse clinical symptoms of pediatric nutcracker phenomenon

AIMS: The nutcracker phenomenon (NCP) is the significant compression of the left renal vein (LRV) by the aorta and superior mesenteric artery (SMA), and found in the patients with so-called idiopathic renal bleeding, orthostatic proteinuria and severe orthostatic intolerance. The purpose of this study is to investigate clinical implications among these disorders possibly related to the NCP. MATERIAL AND METHODS: We analyzed 93 pediatric patients (56 with idiopathic renal bleeding, 14 with massive orthostatic proteinuria and 23 with severe orthostatic intolerance), and the findings of 64 patients were compared on both digital subtraction angiography (DSA) and ultrasonography (US) to obtain a new US classification of the NCP with seven grades. RESULTS: US grades of the NCP were well-correlated with DSA findings (rs = 0.797, p < 0.0001). LRV stenosis was a typical finding in patients with idiopathic renal bleeding. LRV occlusion was observed in 70% for severe orthostatic intolerance, and in contrast in 18% and 14% for idiopathic renal bleeding and massive orthostatic proteinuria, respectively. Collateral veins on color Doppler US as well as a mirror image of the SMA in the aorta on conventional US were found as subsidiary signs of LRV occlusion. Extreme dilatation of the LRV was present in 44% for massive orthostatic proteinuria and in 7% for idiopathic renal bleeding (p < 0.0001). CONCLUSIONS: Anew US classification is useful for the diagnosis of the NCP in diverse clinical symptoms.     

Late outcomes after isolated coronary artery bypass grafting for ischemic mitral regurgitation

Objectives: Although ischemic mitral regurgitation (IMR) is one of the most important issues to determine therapeutic strategy for ischemic heart disease, long-term outcome after coronary artery bypass grafting (CABG) for IMR is still unclear. It is also controversial how patients who would benefit from mitral valve (MV) surgery in combination with CABG should be identified. The purpose of this study is to elucidate late outcomes after isolated CABG for moderate IMR and to assess the indication of combined MV surgery. Methods: Two hundred and seventy-nine patients who had grade 2 or 3 IMR preoperatively and underwent isolated CABG between 1980 and 2002 in our institute were enrolled. Mitral regurgitation was assessed by 2-dimensional Doppler echocardiography and left ventriculography. Among them, 84 patients (30.1%) had left ventricular ejection fraction (LVEF) less than 30% and 186 patients (66.7%) had prior inferior myocardial infarction (MI). Results: One hundred and twenty-nine patients (46.2%) remained grade 2 or greater MR early postoperatively. Actuarial survival and freedom from cardiac events, analyzed by the Kaplan-Meier method, were 90.9% and 87.7% at 1 year, 79.2% and 68.8% at 5 years, 54.9% and 49.1% at 10 years and 48.8% and 18.9% at 15 years. Independent predictive risk factors for cardiac events, analyzed by multivariate analysis using the Cox proportional hazard model, were grade 2 or greater MR which remained early postoperatively (p=0.0002), LVEF<30% preoperatively (p=0.0006), no inferior MI preoperatively (p=0.007) and no internal thoracic artery-left anterior descending artery graft (p=0.049). More than a 15% decrease in LVEF at more than 3 years after the operation was seen despite patent bypass grafts in 17.2% of patients who received a late follow-up catheterization, although 41.4% of patients showed an increase or less than 5% decrease in LVEF during this period. Conclusion: Combined MV surgery with CABG for IMR should be considered in patients with poor LVEF or without prior inferior MI.     

Herbert screw fixation of capitellar fractures

From 1993 to 2003, 6 patients with displaced fractures of the humeral capitellum were treated by open reduction and internal fixation of the capitellar fragments with Herbert bone screws. By use of the criteria of Grantham et al, there were 2 type II-A fractures, 1 type II-B fracture, 1 type II-C fracture, and 2 type III-A fractures. A lateral approach was used in 4 patients and a posterior approach with olecranon osteotomy in 2. The elbows were immobilized postoperatively for 4 to 28 days (mean, 13.5 days). We evaluated the range of motion, stability, and pain using the criteria of Grantham et al. The follow-up period ranged from 2.5 to 9.3 years (mean, 5.6 years). All patients had a stable, pain-free elbow with good range of motion at follow-up. All fractures healed, and there was no evidence of avascular necrosis or degenerative change.     

微型Doppler和内窥镜在脑动脉瘤手术中的应用

目的 探讨Doppler微型探头和硬性神经内窥镜在脑动脉瘤手术中的应用价值.方法 2005 年4月至 2006年7月,96位脑动脉瘤患者在手术中同时应用Doppler和内窥镜,动脉瘤数为107个.Doppler探头的直径为 1.5 mm,频率为 20 MHz;内窥镜有0、30、70三种角度.在动脉瘤夹闭前和(或)夹闭后使用Doppler和神经内窥镜.结果 107个动脉瘤中的39个动脉瘤,内窥镜提供了显微镜所没有提供的信息;19例在内窥镜和Doppler探查后对动脉瘤夹进行了调整,其中10例因瘤颈不完全夹闭, 9例因穿通支受到动脉瘤夹的影响.结论 Doppler和神经内窥镜在动脉瘤手术中具有应用价值,可在夹闭前和(或)夹闭后应用.     

Early colon cancers detected by FDG-pet: a report of two cases with immunohistochemical investigation

Increased glucose uptake is one of the metabolic characteristics of tumor cells. 18F-fluorodeoxyglucose (FDG)-positron emission tomography (FDG-PET), a technique that is used widely to study this altered glucose metabolism in tumors, allows the detection of various types of malignancy. We present herein two cases of early colon cancers detected incidentally by FDG-PET. The technique was used as part of the screening examinations for preoperative staging, and for postoperative follow-up. In both cases, the lesions were removed by colonoscopic polypectomy, with no complications. Moreover, we confirmed the existence of altered glucose metabolism in the resected specimen by immunohistochemical staining using an antibody raised against Glut1. Immunohistochemically, Glut1 was expressed in vitro in both of the lesions, supporting the positive FDG-PET result obtained in vivo. To our knowledge, this is the first report to describe in vitro Glut1 expression and in vivo tumor detection using FDG-PET in colorectal carcinoma.     

Pathological findings of the aortic homograft in a patient with tetralogy of Fallot twenty years after implantation

Summary We report pathological findings of the aortic homograft in a 27-year-old patient who died 20 years after implantation at the time of correction of tetralogy of Fallot. Although calcification of the homograft was severe with degeneration of valve leaflets, no functional obstruction of the homograft was found as a conduit. This observation may suggest a beneficial aspect of the aortic homograft as the right ventricle to the pulmonary artery conduit late after corrective surgery even if calcification was not avoided.     

Therapeutic Dilemma of Sarcoidosis and Treatment-naïve Hepatitis C Manifesting as Tattoo Reactions

A 23-year-old man had an 8-day history of fatigue and dry cough and papulo-nodular reactions on his extensive tattoos. Chest radiography revealed several small granular shadows, and a transbronchial lung biopsy showed non-caseating epithelioid cell granuloma. A skin biopsy of the tattooed area showed histiocytic infiltrates with phagocytized tattoo pigment. Antibody tests for hepatitis C virus were positive. The patient was successfully treated with corticosteroid therapy, and after inflammation was suppressed, he received delayed anti-viral therapy. Sarcoidosis should be considered as a concurrent condition if papules are presented on the tattoos of patients with hepatitis C.