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71.

Background

The clinical course of pT3 upper tract urothelial carcinoma (UTUC) is highly variable.

Objectives

The aim of the current study was to validate the clinical and prognostic importance of pT3 subclassification in the renal pelvicalyceal system in a large international cohort of patients.

Design, setting, and participants

From a multi-institutional international database, 858 renal pelvicalyceal tumors treated with radical nephroureterectomy (RNU) were systematically reevaluated by genitourinary pathologists. Category pT3 pelvic tumors were categorized as pT3a (infiltration of the renal parenchyma on a microscopic level only) versus pT3b (macroscopic infiltration of the renal parenchyma and/or infiltration of peripelvic adipose tissue).

Intervention

RNU.

Measurements

Associations of pT3 subclassifications with clinicopathologic features were assessed with the chi-square test. Prognostic impact was assessed with the log-rank test and multivariable Cox regression analyses.

Results and limitations

Of 858 patients with renal pelvicalyceal tumors, 266 (31%) had pT3 disease. Of these, 146 (54.9%) were classified as pT3a and 120 (45.1%) as pT3b. Compared with pT3a, pT3b cancers were associated with higher tumor grade, nodal disease, and tumor necrosis. Ten-year recurrence-free (pT3a 58% vs pT3b 38%; p < 0.001) and cancer-specific (pT3a 60% vs pT3b 39%; p = 0.002) survival rates were lower for patients with pT3b disease. In multivariable analyses, classification pT3b was an independent predictor of both disease recurrence (hazard ratio [HR]: 1.8, p = 0.003) and cancer-specific mortality (HR: 1.7; p = 0.02). The major limitation is the retrospective character of the study.

Conclusions

Subclassification of pT3 renal pelvicalyceal UTUC helps identify patients who are at increased risk of disease progression and cancer-related death. Further research may help assess the value of subclassification and its inclusion in future editions of the American Joint Committee on Cancer–International Union Against Cancer TNM classification system.  相似文献   
72.
PurposeCongenital tracheal stenosis is a rare condition and can be difficult to manage. One source of difficulty is postoperative tracheomalacia requiring long-term tracheal stenting. To prevent symptomatic postoperative tracheomalacia, we have been adding aortopexy to tracheal reconstruction since 2008. The aim of this study was to evaluate efficacy of aortopexy for preventing postoperative tracheomalacia after reconstruction of congenital tracheal stenosis.MethodsRetrospective chart review was conducted. From October 2003 to March 2011, 24 had tracheal reconstruction without aortopexy (group A) and 8 with aortopexy (group B). Statistical analysis was performed using Fisher's Exact test.ResultsOne had anastomotic leakage in group A, and 1, in group B (P = .44). Eleven patients required tracheostomy because of postoperative tracheomalacia confirmed by postoperative bronchoscopy in group A vs none in group B (P = .029).ConclusionsWe found that aortopexy with tracheal reconstruction reduced the need for postoperative tracheostomy in this patient group. Although there is a potential risk of anastomotic leakage because of the suspension suture on the anterior tracheal wall to aorta, we did not detect an increased incidence after aortopexy. Thus, aortic suspension may be a useful adjunct to prevent symptoms of tracheomalacia in these patients.  相似文献   
73.
Spontaneous perforation of a choledochal cyst with ensuing pseudocyst formation is a very rare complication. We report the development of a pseudocyst adjacent to a choledochal cyst in a very low-birth-weight infant at 2 months of age. Elective excision of the choledochal cyst and biliary tract reconstruction were successfully performed 2 months later when the infant weighed 3 kg. Delayed primary repair may be a viable alternative treatment for low-birth-weight infants with choledochal cysts.  相似文献   
74.

Purpose

To describe the natural history and identify predictors of cancer-specific survival in patients who experience disease recurrence after radical nephroureterectomy (RNU) for upper tract urothelial carcinoma (UTUC).

Methods

Of 2,494 UTUC patients treated with RNU without neoadjuvant chemotherapy, 597 patients experienced disease recurrence. A total of 148 patients (25?%) received adjuvant chemotherapy before disease recurrence. Multivariable Cox regression model addressed time to cancer-specific mortality after disease recurrence.

Results

The median time from RNU to disease recurrence was 12?months (interquartile range 5?C22). A total of 491 (82?%) of 597 patients died from UTUC, and 8 patients (1.3?%) died from other causes. The median time from disease recurrence to death of UTUC was 10?months. Actuarial cancer-specific survival estimate at 12?months after disease recurrence was 35?%. On multivariable analysis that adjusted for the effects of standard clinicopathologic characteristics, higher tumor stages [hazard ratio (HR) pT3 vs. pT0?CT1: 1.66, p?=?0.001; HR pT4 vs. pT0?CT1: 1.90, p?=?0.002], absence of lymph node dissection (HR 1.28, p?=?0.041), ureteral tumor location (HR 1.44, p?<?0.0005) and a shorter interval from surgery to disease recurrence (p?<?0.0005) were significantly associated with cancer-specific mortality. The adjusted 6-, 12- and 24-month postrecurrence cancer-specific mortality was 73, 60 and 57?%, respectively.

Conclusions

Approximately 80?% of patients who experience disease recurrence after RNU die within 2?years after recurrence. Patients with non-organ-confined stage, absence of lymph node dissection, ureteral tumor location and/or shorter time to disease recurrence died of their tumor more quickly than their counterparts. These factors should be considered in patient counseling and risk stratification for salvage treatment decision making.  相似文献   
75.
ObjectiveCarcinoma in situ (CIS) is associated with increased risk of progression when found with high-grade non-muscle-invasive bladder cancer, yet its impact is less clear in the upper urinary tract. In the current study, we evaluated the impact of concomitant CIS on recurrence-free survival and cancer-specific survival following radical nephroureterectomy for upper tract urothelial carcinoma (UTUC).Materials and methodsA multi-institutional retrospective cohort of 1,387 patients undergoing radical nephroureterectomy was identified. Concomitant CIS was defined as the presence of CIS in association with another pathologic stage; patients with CIS alone were excluded from the analysis. The presence of concomitant CIS served as the exposure variable with disease recurrence and cancer-specific mortality as the outcomes. Organ-confined disease was defined as AJCC/UICC stage II or lower.ResultsConcomitant CIS was identified in 371 of 1,387 (26.7%) patients and was significantly more common in patients with a previous bladder cancer history, high grade, and high stage tumors. In a multivariable analysis, concomitant CIS was a predictor of disease recurrence (HR = 1.25, P = 0.04) and cancer specific mortality (HR = 1.34, P = 0.05) for patients with organ-confined UTUC, but not in the entire cohort. Other prognostic variables, such as grade, stage, lymphovascular invasion, and lymph node status, were associated with poorer overall and recurrence-free survival for all patients.ConclusionThe presence of concomitant CIS in patients with organ-confined UTUC is associated with a higher risk of recurrent disease and cancer-specific mortality. This information may be useful in refining surveillance protocols and in more appropriate selection of patients for adjuvant chemotherapy.  相似文献   
76.
Quality of life in patients with spinal osteoporosis is impaired by the decline of spinal mobility. However, the factors related to the spinal mobility in these patients are still unclear. We evaluated the possible factors affecting spinal mobility in patients with postmenopausal osteoporosis. A total of 128 postmenopausal women with osteoporosis aged over 50 years (mean, 70 years) were included in this study. The thoracic and lumbar kyphosis angles and range of motion (ROM) of the total spine were measured in the upright position and at maximum flexion/extension with a computer-assisted device. The paravertebral muscle thicknesses (PVMT) of thoracic and lumbar spine in the upright position were measured using an ultrasound unit. The number of vertebral fractures was evaluated with radiographs of the spine. Isometric back extensor strength (BES) was evaluated with a strain-gauge dynamometer. Correlations between these variables were then analyzed. Age ( r =–0.412), lumbar kyphosis angle ( r =–0.284), BES ( r =0.369), PVMT at the lumbar spine ( r =0.227) and the number of vertebral fractures ( r =–0.260) showed significant correlations with total spinal ROM ( P <0.05). However, no significant correlations were observed between the total spinal ROM and PVMT at the thoracic spine ( r =–0.069) or thoracic kyphosis angle ( r =–0.138). Multiple regression analysis revealed that the BES was the most significant contributor to the total spinal ROM. The present study suggests a possible association between BES and spinal mobility in patients with postmenopausal osteoporosis.  相似文献   
77.
The Japanese Society of Nuclear Medicine has recently published the consensus guidelines for pediatric nuclear medicine. This article is the English version of the guidelines. Part 1 proposes the dose optimization in pediatric nuclear medicine studies. Part 2 comprehensively discusses imaging techniques for the appropriate conduct of pediatric nuclear medicine procedures, considering the characteristics of imaging in children.  相似文献   
78.
The current positron emission tomography (PET) design is aimed toward establishing an entire-body PET scanner. An entire-body PET scanner is a scanner whose axial field of view (FOV) covers the whole body of a patient, whereas whole-body PET scanner can be of any axial FOV length, but was designed for a whole-body scan. Despite its high production cost, an entire-body depth-of-interaction PET scanner offers many benefits, such as shorter and dynamic PET time acquisition, as well as higher sensitivity and count rate performance. This PET scanner may be cost-effective for clinical PET scanners with high scan throughput. In this work, we evaluated the sensitivity and count rate performance of a 2-m-long PET scanner with conventional data acquisition (DAQ) architecture, using Monte Carlo simulation, and we evaluated two ring diameters (60 and 80 cm) to reduce the scanner cost. From simulation of scanning with a 2-m axial FOV, the sensitivity for a 2-m-long PET scanner of 60 and 80-cm diameter is around 80 and 68 times higher, respectively, than that of the conventional PET scanner. In addition, for the 2-m-long PET scanner with 60-cm diameter, the peak noise equivalent count rate (NECR) was 843 kcps at 125 MBq, whereas the peak for the 80-cm diameter was 989 kcps at 200 MBq. This shows gains of 15.3 and 17.95, respectively, in comparison with that of the conventional PET scanner. The 2-m-long PET scanner with 60-cm ring diameter could not only reduce the number of detectors by 21 %, but also had a 17 % higher sensitivity compared to that with an 80-cm ring diameter. On the other hand, despite the higher sensitivity, the NECR of the 60-cm ring diameter was smaller than that of the 80-cm ring diameter. This results from the single data loss due to dead time, whereas grouping of axially stacked detectors was used in the conventional DAQ architecture. Parallelization of the DAQ architecture is therefore important for the 2-m-long PET scanner to achieve its optimal performance.  相似文献   
79.
In the development of depth-of-interaction (DOI)-positron emission tomography (PET) detectors, one of the important steps toward their practical use is an evaluation of their imaging performance, such as the spatial resolution as measured by use of a point source and a one-pair experimental system which simulates actual PET geometries. The DOI-PET detectors have a broad field of view providing good imaging performance compared with conventional detectors. Therefore, evaluation including the region from the center to the periphery close to the detector ring is required in an effort to show their advanced performance regarding uniform spatial resolution. In this study, we aimed to develop and evaluate an efficient one-pair experimental system for demonstration of the DOI-PET detector performance. For this purpose, we propose a one-pair experimental system that can simulate an arbitrary ring diameter and acquire projection data efficiently by skipping unnecessary combinations according to the position of the point source. As a result, the proposed system and our measuring scheme could significantly reduce the total measurement time, especially for a large ring size such as that used in brain PET scanners and whole-body PET scanners. We used the system to evaluate the X’tal cube PET detector with a 2-mm cubic crystal array arranged in simulated PET geometries with ring diameters of 8.2 and 14.6 cm for 12 and 18 detector blocks, respectively. The results showed that a uniform spatial resolution was achieved even in the peripheral region, and measurements were obtained semi-automatically in a short time.  相似文献   
80.
To study the immunological and metabolic effects of auxiliary liver transplantation (ALT), a simple ALT model in rats was developed using the cuff application. Effects of transient parking of normal liver were tested in congenitally hyperbilirubinemic Gunn rats. Serum bilirubin concentrations in Gunn rats, transplanted heterotopically with normal livers of Wistar rats, were dramatically reduced and maintained within normal levels. The graftectomy was performed safely 1 month after transplantation, but total bilirubin levels did not return to the preoperative value of the Gunn rats. It is possible that hepatic stem cells included in ALT liver migrated to the host liver and differentiated into cells capable of producing certain enzymes. © 1998 Wiley-Liss, Inc. MICROSURGERY 18:97-102 1998  相似文献   
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