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41.
OBJECTIVES: Some patients and oncologists choose to treat localized esophageal cancer with definitive chemotherapy and radiation therapy rather than surgery. A subset of these patients have local relapse without distant metastases and therefore have no other curative intent treatment option but salvage esophagectomy. METHODS: We reviewed our experience with salvage esophagectomy from 1987 to 2000 at M.D. Anderson Cancer Center (n = 13, salvage after chemotherapy and radiotherapy group) and compared the data with those of patients receiving esophagectomy in a planned fashion 4 to 6 weeks after preoperative chemotherapy and radiation therapy (n = 99, preoperative chemotherapy and radiotherapy group). RESULTS: Increases in morbidity were seen after resection in the salvage after chemotherapy and radiotherapy group relative to the preoperative chemotherapy and radiotherapy group: mechanical ventilation (9.0 days vs 3.3 days, P =.08), intensive care unit stay (11.2 days vs 5.1 days, P =.07), hospital stay (29.4 days vs 18.4 days, P =.03), and anastomotic leak rates (5/13 [39%] vs 7/99 [7%], P =.005). Operative mortality (within 30 days) also tended to be increased statistically nonsignificantly (2/13 [15%] vs 6/99 [6%], P =.2). Salvage esophagectomy resulted in long-term survival (25% 5-year survival) in a subset of patients. Improved survival after salvage esophagectomy was associated with early pathologic stage (T1 N0, T2 N0), prolonged time to relapse, and R0 surgical resection. CONCLUSION: Patients who undergo salvage esophagectomy for relapse of tumor after definitive chemoradiation therapy have increased morbidity, mortality, and hospital use relative to patients undergoing planned esophagectomy after preoperative chemoradiation. Nevertheless, long-term survival can be achieved in this group, and such treatment should be considered for carefully selected patients at an experienced center.  相似文献   
42.
The presence of mucin pools lacking neoplastic epithelium ("acellular" mucin) in resection specimens of rectal carcinoma after neoadjuvant chemoradiotherapy (CRT) is a well-recognized phenomenon. The current recommendation by the College of American Pathologists is to regard acellular mucin as a type of treatment response and not as residual tumor. However, data-based evidence for or against such an approach is incomplete. In this study, we systematically analyzed the pattern and significance of mucin pools in 108 consecutive, prospectively collected resection specimens from patients who had uT3-4 and/or uN1 rectal cancer and were treated with preoperative long-course CRT. The 108 patients, 39 female and 69 male, had a median age of 58.5 years. With every tumor entirely examined in whole-mount sections, mucin pools were identified in 33 cases (33 of 108, 31%); in 16 (15%) they were all acellular. The mucin pools were focal (10% to 50% of the entire lesion) in 25 cases and extensive (>50%) in 8 cases. Mucin pools were also noted in the lymph nodes in 6 cases (6%); 3 of these were entirely acellular. Five cases had mucin pools in both the primary site and the lymph nodes. When acellular mucin was considered as "no residual tumor," the complete pathologic response rate for the entire cohort was 22% (24 of 108). The pathologic stage of the residual tumor (ypT) was 0 or 1 for 27 cases (25%) and 2 to 4 for 81 cases. The pathologic stage of nodal disease (ypN) was 0 for 83 (77%) and 1 or 2 for 25 cases. When acellular mucin was considered as "residual tumor," the complete pathologic response rate dropped to 17%; ypT was upstaged in 10 tumors and ypN was upstaged in 2 tumors. With a median follow-up of 31 months, the 3-year recurrence-free survival (RFS) was 73% for the entire group. Advanced pathologic response and low pathologic stage of the residual tumor (determined based on the depth of only viable tumor cells) correlated significantly with better RFS. However, the correlation between pathologic response and RFS became insignificant when acellular mucin pools were considered as residual tumor. Neither the presence of mucin pools nor their extent or cellularity had an impact on RFS. Furthermore, none of the 12 patients whose ypT or ypN was upstaged by acellular mucin had recurrent disease (3-y RFS of 100%). Thus, our results suggest that mucin pools in rectal carcinoma after neoadjuvant CRT do not have a significant impact on patient outcome, supporting the College of American Pathologists recommendation that only viable tumor cells, not acellular mucin, are to be interpreted as residual disease in the tumor pathologic staging.  相似文献   
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44.
A biologically active human skin allograft, currently distributed under the brand name TheraSkin(?), was examined for safety and efficacy in the treatment of venous leg ulcers (VLUs) and diabetic foot ulcers (DFUs). The objective was to determine if TheraSkin could serve as a safe and effective alternative to bioengineered skin substitutes such as Apligraf(?) and Dermagraft(?). The authors conducted a retrospective study of 214 consecutive patients seen at the Inova Wound Center (Mt Vernon, Virginia), with either a DFU or a VLU. After excluding patients who did not meet the study criteria, the final eligible cohort consisted of 188 subjects, with 134 VLUs and 54 DFUs. Multivariate logistic regression was used to evaluate the relationship between baseline wound size and the proportion of healed wounds after 12 and 20 weeks from initial allograft application. The authors found that by the 12th week, DFUs closed 60.38% of the time and VLUs closed 60.77% of the time. After 20 weeks, the number of closed DFUs increased to 74.1% and the number of VLUs increased to 74.6%. The mean wound size in the DFU group was 6.2 cm(2) (±11.8) and 11.8 cm(2) (±22.5) in the VLU group. The mean number of TheraSkin allografts required ranged from 1 to 8, with an average of 2.03 (±1.47) at the 12-week point and an average of 3.23 (±2.77) at the 20-week point. Multivariate logistic regression was used to calculate the odds of wound healing by week 12 and week 20 in each group. The authors also analyzed adverse events and found TheraSkin to be noncontributory to any adverse events, verifying the safety of TheraSkin in this study population. In this study, TheraSkin has been shown to be highly effective for the treatment of both VLUs and DFUs with an acceptable safety profile.  相似文献   
45.
BACKGROUND: The purpose was to assess the current variation in complication rates and evaluate the association between specific types of complications and in-hospital mortality and total hospital charges for patients having abdominal aortic surgery. PATIENTS/METHODS: We studied 2987 patients for abdominal aortic surgery in Maryland from 1994 to 1996 and used discharge diagnoses and procedure codes to identify diagnoses that most likely represent major surgery complications. We evaluated how in-hospital mortality and total hospital charges related to specific complications, adjusting for patient demographics, severity of illness, comorbidity, and hospital and surgeon volumes. Discharge data was obtained from the hospital marketing departments. RESULTS: Complication rates varied widely among hospitals. Complications independently associated with increased risk of in-hospital death include cardiac arrest with an odds ratio (OR) of 90 and a 95% confidence interval (CI) of 32-251, septicemia (OR 6.1, CI 3.3-11.3), acute myocardial infarction (OR 5.7, CI 2.3-14.3), acute renal failure (OR 5.0, CI 2.3-11.0), surgical complications after a procedure (OR 3.1, CI 2.0-4.9), and reoperation for bleeding (OR 2.2, CI 1.1-4.8). The population-attributable risk for in-hospital mortality was 47% for cardiac arrest and 27% for acute renal failure. CONCLUSIONS: In abdominal aortic surgery on patients in Maryland, the rates of some complications vary widely and are independently associated with increased in-hospital mortality and hospital charges (charges differ from costs). Efforts to reduce these complications should help to decrease both levels.  相似文献   
46.
47.
Weinhold PS  Stewart JD  Liu HY  Lin CF  Garrett WE  Yu B 《Injury》2007,38(8):973-978
BACKGROUND: Studies have shown that women are at higher risk of sustaining noncontact anterior cruciate ligament (ACL) injuries in specific sports. Recent gait studies of athletic tasks have documented that gender differences in knee movement, muscle activation, and external loading patterns exist. The objective of this study was to determine in a knee cadaver model if application of female-specific loading and movement patterns characterised in vivo for a stop-jump task cause higher ACL strains than male patterns. METHODS: Gender-specific loading patterns of the landing phase of the vertical stop-jump task were applied to seven cadaver knees using published kinetic/kinematic results for recreational athletes. Loads applied consecutively included: tibial compression, quadriceps, hamstrings, external posterior tibial shear, and tibial torque. Knee flexion was fixed based on the kinematic data. Strain of the ACL was monitored by means of a differential variable reluctance transducer installed on the anterior-medial bundle of the ACL. FINDINGS: The ACL strain was significantly increased (P<0.05) for the female loading pattern relative to the male loading pattern after the posterior tibial shear force was applied, and showed a similar trend (P=0.1) to be increased after the final tibial torque was applied. INTERPRETATION: This study suggests that female motor control strategies used during the stop-jump task may place higher strains on the ACL than male strategies, thus putting females at greater risk of ACL injury. We believe these results suggest the potential effectiveness of using training programs to modify motor control strategies and thus modify the risk of injury.  相似文献   
48.
Lymph node metastasis in T1 adenocarcinoma of the colon and rectum   总被引:11,自引:0,他引:11  
The biology of colorectal cancer differs according to location within the large intestine. To evaluate the clinical significance of tumor location as a risk factor for lymph node metastasis (LNM), we performed a detailed pathological review of T1 adenocarcinomas of the colon and rectum. T1 adenocarcinomas of the colon and rectum treated by radical resection (n = 428) were identified from prospective clinical databases at two institutions. Tumor location was assigned as right colon (cecum to transverse), left colon (splenic flexure to sigmoid), or rectum (0–18 cm from AV). Pathology slides were reviewed, extent of submucosal invasion (sm width, sm depth) was quantified using an optical micrometer, and morphologic features of the cancer and its infiltrating margin were recorded. The overall rate of LNM was 10%. On univariate analysis, LNM was significantly more common in the rectum (27/176, 15%) compared to the left colon (13/160, 8%, p = .04) or right colon (3/92, 3%, p = .003). However, on multivariate analysis, deep submucosal invasion and lymphovascular invasion were independent and significant risk factors, whereas tumor location was not. T1 colorectal cancers have a progressively higher risk of LNM as their location becomes more distal. However, the increasing rate of LNM observed in cancers of the left colon and rectum is explained by a higher prevalence of high-risk pathologic features. In early colorectal cancers, tumor morphology is the strongest clinical predictor of metastatic behavior. Presented at the Forty-Fifth Annual Meeting of The Society for Surgery of the Alimentary Tract, New Orleans, Louisiana, May 15–19, 2004 Presented at the Forty-Fifth Annual Meeting of The Society for Surgery of the Alimentary Tract, New Orleans, Louisiana, May 15–19, 2004  相似文献   
49.
Objective: Objectives were to evaluate latency-based brief functional analysis (BFA) model for identifying functions of aberrant behavior and treatments generated based on the results of the latency-based brief functional analysis. Methods: We conducted latency-based BFA, including contingency reversals, and function-based treatment evaluations, including non-contingent reinforcement (NCR) and differential reinforcement of alternative behavior (DRA) with three individuals with autism using single subject design methodology. Results: Socially-mediated functions (attention; tangible) were indicated for two participants and an automatic function was identified for one participant. The treatments generated based on results of the BFA were effective at reducing aberrant behavior for all participants. Conclusions: Results provide additional support that latency-based BFA model has utility in (a) the identification of functions of aberrant behavior and (b) the generation of function-based treatments. These results suggest clinicians who encounter setting and client-specific constraints (e.g. time; severity of aberrant behavior) have additional flexibility in choosing assessment tools.  相似文献   
50.
The outcomes of 18 primary or revision total hip (THA) and knee arthroplasties (TKA) in 9 patients with cardiac transplants were reviewed. Primary total joint arthroplasties were performed for osteonecrosis (5 hips) or osteoarthritis (5 hips, 4 knees). There were no infections in any of these patients. Final Harris Hip Scores were 71.8 for patients with osteonecrosis and 88.6 for osteoarthritis. Eight of 10 hips were pain-free at final follow-up. Two of the 10 primary THAs required late revision at 7 and 10 years after the index arthroplasty. One patient (2 hips and 1 knee) had chronic bilateral lower extremity pain. Total knee arthroplasty range of motion averaged from 7.5° to 118°. Average final Knee Society function score was 79, and objective score was 88. One of 4 patients with primary TKA required a manipulation under anesthesia. No reoperations were required in this group. Overall, patients with heart transplantations on immunosuppression had generally good pain relief after THA and TKA. There were no infections in this small cohort; however, there were many complications.  相似文献   
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