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41.
42.
BACKGROUND: Dissimilarities in management and outcomes exist between upper tract urothelial carcinoma (UTUC) and urothelial carcinoma of the bladder (UCB). OBJECTIVE: The aim of this study was to analyze the stage-specific impact of upper or lower urinary tract tumor location on oncologic outcomes. DESIGN, SETTING, AND PARTICIPANTS: Data were collected from 4335 patients with UCB treated with radical cystectomy (RC) and bilateral pelvic lymphadenectomy (PLND), 877 patients with ureteral UTUC, and 1615 with pelvicalyceal UTUC treated with radical nephroureterectomy (RNU). No patient received preoperative chemotherapy or radiation therapy. INTERVENTIONS: Patients were treated with RC and bilateral PLND or RNU. MEASUREMENTS: Outcomes were assessed according to primary tumor location. RESULTS AND LIMITATIONS: Compared to UTUC patients, UCB patients had more advanced tumor stage and higher grade, and they were more likely to harbor lymphovascular invasion (LVI) and lymph node metastasis (p<0.001). In non-muscle-invasive tumor stages, UCB patients were more likely to experience disease recurrence and mortality compared to renal pelvicalyceal tumor patients (p<0.002) but not ureteral tumors (p>0.05). In pT2 and pT3 tumors, there was no difference in outcomes between the three tumor locations. In pT4 tumors, patients with ureteral and pelvicalyceal tumors were more likely to experience disease recurrence and mortality compared to UCB patients (p<0.004). These stage-specific findings were unchanged after adjustment for the effects of age, gender, tumor grade, LVI, lymph node status, and adjuvant chemotherapy. This study is limited by its retrospective and multicenter nature. CONCLUSIONS: Stage-specific differences in outcomes exist between UCB and UTUC. The differentially worse outcomes by stage between UCB and UTUC patients underline the differences between both cancer entities and the need for individualized stage-specific management for each patient.  相似文献   
43.
We investigated the median nerve deformation in the carpal tunnel in patients with carpal tunnel syndrome and controls during thumb, index finger, middle finger, and a four finger motion, using ultrasound. Both wrists of 29 asymptomatic volunteers and 29 patients with idiopathic carpal tunnel syndrome were evaluated by ultrasound. Cross‐sectional images during motion from full extension to flexion were recorded. Median nerve cross‐sectional area, perimeter, aspect ratio of the minimal enclosing rectangle, and circularity in extension and flexion positions were calculated. Additionally, a deformation index was calculated. We also calculated the intra‐rater reliability. In both controls and patients, the median nerve cross‐sectional area became significantly smaller from extension to flexion in all finger motions (p < 0.05). In flexion and extension, regardless of the specific finger motion, the median nerve deformation, circularity and the change in perimeter were all significantly greater in CTS patients than in controls (p < 0.05). We found excellent intra‐rater reliability for all measurements (ICC > 0.84). With this study we have shown that it is possible to assess the deformation of the median nerve in carpal tunnel syndrome with ultrasonography and that there is more deformation of the median nerve in carpal tunnel syndrome patients during active finger motion. These parameters might be useful in the evaluation of kinematics within the carpal tunnel, and in furthering our understanding of the biomechanics of carpal tunnel syndrome in the future. © 2011 Orthopaedic Research Society. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 30:643–648, 2012  相似文献   
44.
OBJECTIVE: On November 23, 1992, the first endovascular stent graft (ESG) repair of an aortic aneurysm was performed in North America. Following the treatment of this patient, we have continued to evaluate ESG over the past 10 years in the treatment of 817 patients. SUMMARY AND BACKGROUND DATA: Abdominal (AAA) or thoracic (TAA) aortic aneurysms are a significant health concern traditionally treated by open surgical repair. ESG therapy may offer protection from aneurysm rupture with a reduction in procedure morbidity and mortality. METHODS: Over a 10-year period, 817 patients were treated with ESGs for AAA (723) or TAA (94). Patients received 1 of 12 different stent graft devices. Technical and clinical success of ESGs was reviewed, and the incidence of procedure-related complications was analyzed. RESULTS: The mean age was 74.3 years (range, 25-95 years); 678 patients (83%) were men; 86% had 2 or more comorbid medical illnesses, 67% of which included coronary artery disease. Technical success, on an intent-to-treat basis was achieved in 93.8% of patients. Primary clinical success, which included freedom from aneurysm-related death, type I or III endoleak, graft infection or thrombosis, rupture, or conversion to open repair was 65 +/- 6% at 8 years. Of great importance, freedom from aneurysm rupture after ESG insertion was 98 +/- 1% at 9 years. There was a 2.3% incidence of perioperative mortality. One hundred seventy five patients died of causes not related to their aneurysm during a mean follow-up of 15.4 months. CONCLUSIONS: Stent graft therapy for aortic aneurysms is a valuable alternative to open aortic repair, especially in older sicker patients with large aneurysms. Continued device improvements coupled with an enhanced understanding of the important role of aortic pathology in determining therapeutic success will eventually permit ESGs to be a more durable treatment of aortic aneurysms.  相似文献   
45.
BACKGROUND: The majority of patients with hepatocellular carcinoma (HCC) who undergo complete tumor resection subsequently develop tumor recurrence. The objectives of this study were to determine the risk factors for recurrence of HCC after hepatectomy and to examine the outcomes once tumor recurrence occurs. STUDY DESIGN: From February 1990 to May 2001 a total of 164 patients underwent liver resection for HCC at our institution and were prospectively followed. Time to recurrence and survival after recurrence were determined by Kaplan-Meier analysis. Patient, tumor, and treatment characteristics were tested for their prognostic significance by univariate and multivariate analysis using the logrank test and the Cox proportional hazards model, respectively. RESULTS: The median patient age was 64 years (range 21 to 87 years) and 106 patients (65%) were male. After a median followup of 26 months, 90 patients (55%) have developed recurrent cancer. Among them, 75 patients (83%) had tumor detectable in the liver, which was the only site of disease in 67 (74%). In all, 15 patients (20%) had extrahepatic disease (7 lung, 4 peritoneum, 2 pancreas, 1 bone, and 1 brain). The median time to recurrence was 24 months (range 1 to 274 months). Predictors of recurrence on univariate analysis were tumor size greater than 5 cm, more than one tumor, cirrhosis, vascular invasion (microscopic or macroscopic), and tumor satellites. On multivariate analysis only tumor size greater than 5 cm (p = 0.04) and vascular invasion (p = 0.01) predicted recurrence. The median survival after recurrence was 11 months (range 0 to 60 months). Of the 90 patients who developed tumor recurrence 49 (67%) were able to undergo additional ablative or surgical therapy (33 embolization, 9 ethanol injection, and 14 re-resection). On multivariate analysis vascular invasion in the original tumor predicted poor survival after recurrence (p = 0.009). CONCLUSIONS: The liver is the predominant site of first recurrence after resection of hepatocellular carcinoma, and once recurrence occurs survival is limited. The current study underscores the need for effective adjuvant therapy for patients with HCC treated with partial hepatectomy.  相似文献   
46.
OBJECTIVE: To assess the results of multimodality therapy for patients with recurrent rectal cancer and to analyze factors predictive of curative resection and prognostic for overall survival. SUMMARY BACKGROUND DATA: Locally recurrent rectal cancer is a difficult clinical problem, and radical treatment options with curative intent are not generally accepted. METHODS: A total of 394 patients underwent surgical exploration for recurrent rectal cancer. Ninety were found to have unresectable local or extrapelvic disease and 304 underwent resection of the recurrence. The latter patients were prospectively followed to determine long-term survival and factors influencing survival. RESULTS: Overall 5-year survival was 25%. Curative, negative resection margins were obtained in 45% of patients; in these patients a 5-year survival of 37% was achieved, compared to 16% (P <.001) in patients with either microscopic or gross residual disease. In a logistic regression analysis, initial surgery with end-colostomy and symptomatic pain (both univariate) and increasing number of sites of the recurrent tumor fixation in the pelvis (multivariate) were associated with palliative surgery. Overall survival was significantly decreased for symptomatic pain (P <.001) and more than one fixation (P =.029). Survival following extended resection of adjacent organs was not different from limited resection (28% vs. 21%, P =.11). Patient demographics and factors related to the initial rectal cancer did not affect outcome. Perioperative mortality was only 0.3%, but significant morbidity occurred in 26% of patients, with pelvic abscess being the most common complication. CONCLUSIONS: This study demonstrates that many patients with locally recurrent rectal cancer can be resected with negative margins. Long-term survival can be achieved, especially for patients with no symptoms and minimal fixation of the recurrence in the pelvis, provided no gross residual disease remains.  相似文献   
47.
PURPOSE: Controversy surrounds the process of morcellation for retrieving laparoscopically removed specimens. The inability to assess tumor stage, increased difficulty in pathological examination and the potential for tumor spillage are cited as significant disadvantages of the technique. We examined cytological findings in bag washings after laparoscopic nephrectomy for benign and malignant diseases. MATERIALS AND METHODS: We prospectively obtained cytology washings from the retrieval bag after laparoscopic nephrectomy and manual morcellation. In 22 consecutive cases after specimen fragmentation in a LapSac (Cook Urological, Spencer, Indiana) the bag was thoroughly irrigated with 30 cc normal saline. This wash was then processed by ThinPrep (Cytyc Corp., Marlborough, Massachusetts) and stained with Papanicolaou stain. Standard pathological examination of the morcellated specimen was performed to determine renal histology. RESULTS: The histological diagnosis was clear cell renal carcinoma in 10 cases, multicystic renal carcinoma in 2, papillary renal cell carcinoma in 1, angiomyolipoma in 1, and oncocytoma in 1. Bag cytological results were accurate in 9 of 13 patients with carcinoma (69%), while in 3 cytological study provided additional information. In all 9 cases of benign histology, cytological findings were consistent with benign cellular features. Neoplastic cells were easily detected and classified into type and grade. CONCLUSIONS: Cytological examination of LapSac washings after specimen morcellation provided a pathological diagnosis in the majority of patients. This method may complement existing techniques and be useful for increasing the accuracy of pathological analysis of morcellated specimens. In addition, these data suggest that malignant cells are liberated during the morcellation process, which has significant implications for potential tumor dissemination.  相似文献   
48.

Objective:

To compare the performance of the 15-G internally cooled electrode with that of the conventional 17-G internally cooled electrode.

Methods:

A total of 40 (20 for each electrode) and 20 ablation zones (10 for each electrode) were made in extracted bovine livers and in in vivo porcine livers, respectively. Technical parameters, three dimensions [long-axis diameter (Dl), vertical-axis diameter (Dv) and short-axis diameter (Ds)], volume and the circularity (Ds/Dl) of the ablation zone were compared.

Results:

The total delivered energy was higher in the 15-G group than in the 17-G group in both ex vivo and in vivo studies (8.78 ± 1.06 vs 7.70 ± 0.98 kcal, p = 0.033; 11.20 ± 1.13 vs 8.49 ± 0.35 kcal, p = 0.001, respectively). The three dimensions of the ablation zone had a tendency to be larger in the 15-G group than in the 17-G group in both studies. The ablation volume was larger in the 15-G group than in the 17-G group in both ex vivo and in vivo studies (29.61 ± 7.10 vs 23.86 ± 3.82 cm3, p = 0.015; 10.26 ± 2.28 vs 7.79 ± 1.68 cm3, p = 0.028, respectively). The circularity of ablation zone was not significantly different in both the studies.

Conclusion:

The size of ablation zone was larger in the 15-G internally cooled electrode than in the 17-G electrode in both ex vivo and in vivo studies.

Advances in knowledge:

Radiofrequency ablation of hepatic tumours using 15-G electrode is useful to create larger ablation zones.Radiofrequency ablation (RFA) is the most widely used local ablation technique for the management of primary and metastatic liver tumours. However, previous studies have reported that RFA showed a relatively higher local tumour progression rate than did hepatic resection.1,2 One of the most important factors affecting local tumour progression was insufficient tumour-free ablation margin of hepatic parenchyma around the tumour margin.36Several strategies have been developed to obtain sufficient ablation margin. In the aspect of RFA techniques, overlapping technique and combined treatment with transcatheter arterial chemoembolization can be used.79 Another strategy is to use switching monopolar, bipolar or multipolar modes to deliver radiofrequency (RF) energy more efficiently.10,11 Sufficient ablation margin can also be achieved by more efficient electrodes: internally cooled electrode increases the size of ablation zone by preventing charring around the electrode tip.12,13 Perfusion electrodes can also enlarge the ablation zone by increasing electrical conductance and thermal conductivity.1416The diameter of an electrode is also known to be associated with the size of the ablation zone. Theoretically, as the diameter of an electrode becomes larger, the contact surface of the electrode with the surrounding tissue becomes bigger, thereby increasing the active electric field.17,18 As a result, an electrode with a larger diameter is likely to create a larger ablation zone. In a previous study, Goldberg et al17 reported that the extent of coagulation necrosis by RFA increases as the diameter of an electrode increases through an in vivo experimental study. However, this study was performed with an electrode without an internal cooling system. Recently, a clinical study comparing therapeutic efficacy and safety between 15-G and 17-G internally cooled electrodes of RFA for hepatocellular carcinoma was published.19 According to that study, the 15-G internally cooled electrode created a larger ablation volume than did the 17-G electrode. However, the study was limited by selection bias owing to the retrospective study design. In addition, the ablation protocol was not exactly the same between the two groups. Therefore, the issue whether an internally cooled electrode with a larger diameter creates a larger ablation volume should be verified with ex vivo and in vivo experimental studies.The purpose of this experimental study was to compare the performance of the 15-G internally cooled RF electrode with that of the conventional 17-G electrode in both ex vivo and in vivo studies.  相似文献   
49.
50.
Abstract:  The purpose of this study was to assess the predictive value of smoking history on breast cancer diagnosis in a referral clinic population. We conducted a case–control study using clinical data collected on 8,097 female patients (1,225 breast cancer cases and 6,872 controls) seen in the Mayo Clinic Breast Clinic between August 1, 1993 and November 31, 2003. Breast cancer patients and noncancer patients significantly differed with respect to age at time of the index visit (p < 0.001), number of pregnancies (p = 0.006), number of live births (p = 0.002), vital status at last known follow-up (p < 0.001), current menstruation (p < 0.001), age at menopause (p < 0.001), history of hysterectomy (p < 0.001), use of oral contraception (p = 0.05), duration of oral contraception use (p = 0.001), use of other exogenous hormones (p < 0.001), duration of exogenous hormone use (p = 0.05), breast pain at time of index visit (p = 0.002), smoking status (p < 0.001), and use of five or more alcoholic beverages per week (p = 0.002). After adjustment for these baseline characteristics, having a personal history of smoking was found to be predictive of breast cancer diagnosis (odds ratios [OR] = 1.25, p = 0.004). Other positive predictors for breast cancer diagnosis were: age (OR = 1.02, p < 0.001), history of hysterectomy (OR = 0.66, p < 0.001), prior use of oral contraception for more than 11 years (OR = 2.10, p < 0.001), and prior use of other exogenous hormones/estrogen (OR = 1.81, p < 0.001). In this referral practice having a personal history of smoking is predictive of breast cancer diagnosis. Further studies are needed to further explore this relationship.  相似文献   
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