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91.
BACKGROUND: My colleagues and I have been using intraoperative frozen-section analysis (FSA) to evaluate lumpectomy margins in an attempt to reduce the number of additional operations that patients with ductal carcinoma in situ or stage I and II breast cancer would have to endure. We review our experience in breast-conservation therapy (BCT) at the University of Florida (Gainesville) to determine the effectiveness of this approach. STUDY DESIGN: Operative reports, operative logs, and pathology reports were retrospectively reviewed for patients who had BCT from January 2001 to January 2004. Ninety-seven patients (116 operations) were reviewed. RESULTS: Nineteen patients required an additional operation (19.6%). Forty-three patients had positive margins on paraffin-embedded histologic analysis (44.3%). Accuracy of FSA was 84% when evaluated on a per-case basis, and 96% on a per-slide basis. False negatives were identified in 22 patients, affecting the operative pathway of 19 patients (19.6%) and were identified more frequently in cases of ductal carcinoma in situ (p < 0.001). There were no false positives. Additional operative time required for FSA was approximately 13 minutes per case. Eighty-four (86.6%) patients had successful BCT and 13 patients (13.4%) required mastectomy. CONCLUSIONS: Intraoperative analysis of margins using FSA is effective at minimizing the number of additional operations, with 19 patients benefiting from immediate intervention in this study. The authors believe that the number of second operations prevented and the high BCT rates justify performing FSA. Ductal carcinoma in situ is more difficult to identify in FSA. Preoperative discussions with the patient should reflect these findings.  相似文献   
92.
Human epidermal growth factor receptor 3 (HER3) is a member of the human epidermal growth factor receptor (HER) family. The main characteristic of HER3 is that it does not possess tyrosine kinase activity, unlike other HERs. The role of HER3 in tumorigenesis has now been recognized, particularly in head and neck squamous cell carcinomas (HNSCCs). Despite conflicting studies, HER3 was found to be overexpressed in HNSCC samples, and correlates with disease progression and poor survival, especially when it is coexpressed with other HERs. HER3 is a significant factor in HNSCC treatment resistance. Indeed, HER3 is a major mechanism described for cetuximab resistance because of modification of epidermal growth factor receptor (EGFR) internalization and by phosphotidylinositol‐3‐kinase (PI3K)/AKT signaling pathway activation. HER3 also affects resistance to tyrosine kinase inhibitors (TKIs) and thereby promotes treatment escape and radiotherapy resistance by activation of the survival signaling pathway. To counteract this, pharmacologic inhibitors of HER3 are currently in development and could significantly improve HNSCC treatment. © 2016 Wiley Periodicals, Inc. Head Neck 38 : E2412–E2418, 2016  相似文献   
93.
The course of autosomal dominant polycystic kidney disease (ADPKD) varies among individuals, with some reaching ESRD before 40 years of age and others never requiring RRT. In this study, we developed a prognostic model to predict renal outcomes in patients with ADPKD on the basis of genetic and clinical data. We conducted a cross-sectional study of 1341 patients from the Genkyst cohort and evaluated the influence of clinical and genetic factors on renal survival. Multivariate survival analysis identified four variables that were significantly associated with age at ESRD onset, and a scoring system from 0 to 9 was developed as follows: being male: 1 point; hypertension before 35 years of age: 2 points; first urologic event before 35 years of age: 2 points; PKD2 mutation: 0 points; nontruncating PKD1 mutation: 2 points; and truncating PKD1 mutation: 4 points. Three risk categories were subsequently defined as low risk (0–3 points), intermediate risk (4–6 points), and high risk (7–9 points) of progression to ESRD, with corresponding median ages for ESRD onset of 70.6, 56.9, and 49 years, respectively. Whereas a score ≤3 eliminates evolution to ESRD before 60 years of age with a negative predictive value of 81.4%, a score >6 forecasts ESRD onset before 60 years of age with a positive predictive value of 90.9%. This new prognostic score accurately predicts renal outcomes in patients with ADPKD and may enable the personalization of therapeutic management of ADPKD.  相似文献   
94.

Background

The safety of laparoscopic major liver resections is still uncertain. The aim of this study was to compare our results for laparoscopic right hepatectomy (LRH) with those for open right hepatectomy (ORH).

Methods

Patients undergoing LRH were compared with retrospectively selected patients from our ORH database. The 2 groups were well matched for sex, age, American Society of Anesthesiologists score, body mass index, liver disease, and tumor size. Surgical and postsurgical outcomes were compared.

Results

Seventy-two patients were analyzed: 22 in the LRH group and 50 in the ORH group. Operating time was similar. Blood loss was significantly less in laparoscopic resections (P = .038). Specific morbidity rates were not different, general morbidity was lower after laparoscopy (P = .04), and the severity of postsurgical complications was not different. Mean hospital stay was significantly shorter after laparoscopy (P = .009).

Comments

Laparoscopy improved surgical and postsurgical outcomes for ORH in selected patients. This is the first comparative study to demonstrate an advantage of laparoscopy for a major liver resection. Prospective randomized studies with a greater number of cases are needed to confirm the role of laparoscopy in major liver resections.  相似文献   
95.
The aim of our study was to assess hepatitis C virus (HCV) evolution and long term liver histology outcome in anti-HCV(+)/RNA(+) renal-transplant (RT) patients. Fifty-five anti-HCV(+)/RNA(+) RT patients underwent every 3-4 years after transplantation liver biopsies (LB) (2 LBs, N = 55; 3 LBs, N = 44; 4 LBs, N = 10). The hypervariable region (HVR)-1 of the HCV genome from all patients was characterized over time. Overall, the rate of liver fibrosis progression was 0.07 +/- 0.03 Metavir units/year. We identified three groups of patients: those in whom liver fibrosis remained stable (group I, N = 21), those with progressing liver fibrosis (group II, N = 21), and those with a regression in liver fibrosis (group III, N = 13). Initial fibrosis stage and high diversification of the HVR-1 of HCV genome between the transplantation and the first liver biopsy were independent factors associated with liver fibrosis regression. In conclusion, in this study, after renal transplantation, HCV infection is not harmful upon liver histology in more than fifty percent of the patients. The diversification of the HVR-1 of the HCV genome might be used to predict liver fibrosis outcome.  相似文献   
96.
Background: Remifentanil-induced secondary hyperalgesia has been documented experimentally in both animals and healthy human volunteers, but never clinically. This study tested the hypotheses that increased pain sensitivity assessed by periincisional allodynia and hyperalgesia can occur after relatively large-dose intraoperative remifentanil and that small-dose ketamine prevents this hyperalgesia.

Methods: Seventy-five patients undergoing major abdominal surgery were randomly assigned to receive (1) intraoperative remifentanil at 0.05 [mu]g [middle dot]kg-1 [middle dot]min-1 (small-dose remifentanil); (2) intraoperative remifentanil at 0.40 [mu]g [middle dot]kg-1 [middle dot]min-1 (large-dose remifentanil); or (3) intraoperative remifentanil at 0.40 [mu]g [middle dot]kg-1 [middle dot]min-1 and 0.5 mg/kg ketamine just after the induction, followed by an intraoperative infusion of 5 [mu]g [middle dot] kg-1 [middle dot] min-1 until skin closure and then 2 [mu]g [middle dot]kg-1 [middle dot]min-1 for 48 h (large-dose remifentanil-ketamine). Pain scores and morphine consumption were recorded for 48 postoperative hours. Quantitative sensory tests, peak expiratory flow measures, and cognitive tests were performed at 24 and 48 h.

Results: Hyperalgesia to von Frey hair stimulation adjacent to the surgical wound and morphine requirements were larger (P < 0.05) and allodynia to von Frey hair stimulation was greater (P < 0.01) in the large-dose remifentanil group compared with the other two groups, which were comparable. There were no significant differences in pain, pressure pain detection threshold with an algometer, peak flow, cognitive tests, or side effects.  相似文献   

97.
OBJECTIVES: We sought to evaluate the safety of a right axillary incision, a cosmetically superior approach than anterolateral thoracotomy, to repair various congenital heart defects. METHODS: All the patients who were approached with this incision between March 2001 and October 2004 were included in the study. There were 80 patients (median age, 4 years) with atrial septal defect closure (38 patients), repair of partial abnormal pulmonary venous return (14 patients), partial atrioventricular canal (16 patients), and perimembranous ventricular septal defect (12 patients). The surgical technique involved peripheral and central cannulation for institution of cardiopulmonary bypass. Electrically induced ventricular fibrillation was used for defects located in front of the atrioventricular valves, and cardioplegic arrest was used for those located at the level or behind these valves. RESULTS: The repair was possible without need for conversion to another approach. One patient sustained a transient neurologic deficit. The patients were all in excellent condition after a mean follow-up of 14 months. The cardiac defect was repaired with no residual defect in 75 patients and with trivial residual defect in 5 patients (3 with mitral valve regurgitation, 1 with atrial septal defect, and 1 with ventricular septal defect). The incision healed properly in all, and the thorax showed no deformity. CONCLUSION: The right axillary incision provides a quality of repair for various congenital defects similar to that obtained by using standard surgical approaches. Because it lies more laterally and is hidden by the resting arm, it provides superior cosmetic results compared with conventional incisions, including the anterolateral thoracotomy. Finally, the incision is unlikely to interfere with subsequent development of the breast.  相似文献   
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