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41.

Background

Patients with colorectal liver metastases (CLM) are increasingly treated with preoperative chemotherapy. Chemotherapy associated liver injury is associated with postoperative hepatic insufficiency (PHI) and mortality. The adequate minimum future liver remnant (FLR) volume in patients treated with extensive chemotherapy remains unknown.

Methods

All patients with standardized FLR > 20 %, who underwent extended right hepatectomy for CLM from 1993-2011, were divided into three cohorts by chemotherapy duration: no chemotherapy (NC, n = 30), short duration (SD, ≤12 weeks, n = 78), long duration (LD, >12 weeks, n = 86). PHI and mortality were compared by using uni-/multivariate analyses. Optimal FLR for LD chemotherapy was determined using a minimum p-value approach.

Results

A total of 194 patients met inclusion criteria. LD chemotherapy was significantly associated with PHI (NC + SD 3.7 vs. LD 16.3%, p = 0.006). Ninety-day mortality rates were 0 % in NC, 1.3 % in SD, and 2.3% in LD patients, respectively (p = 0.95). In patients with FLR > 30 %, PHI occurred in only two patients (both LD, 2/20, 10 %), but all patients with FLR > 30 % survived. The best cutoff of FLR for preventing PHI after chemotherapy >12 weeks was estimated as >30 %. Both LD chemotherapy (odds ratio [OR] 5.4, p = 0.004) and FLR ≤ 30 % (OR 6.3, p = 0.019) were independent predictors of PHI.

Conclusions

Preoperative chemotherapy >12 weeks increases the risk of PHI after extended right hepatectomy. In patients treated with long-duration chemotherapy, FLR > 30 % reduces the rate of PHI and may provide enough functional reserve for clinical rescue if PHI develops.  相似文献   
42.

Background

Few data exist to guide oncologic surveillance following curative treatment of pancreatic cancer. We sought to identify a rational, cost-effective postoperative surveillance strategy.

Methods

We constructed a Markov model to compare the cost-effectiveness of 5 postoperative surveillance strategies. No scheduled surveillance served as the baseline strategy. Clinical evaluation and carbohydrate antigen (CA) 19-9 testing without/with routine computed tomography and chest X-ray at either 6- or 3-month intervals served as the 4 comparison strategies of increasing intensity. We populated the model with symptom, recurrence, treatment, and survival data from patients who had received intensive surveillance after multimodality treatment at our institution between 1998 and 2008. Costs were based on Medicare payments (2011 US dollars).

Results

The baseline strategy of no scheduled surveillance was associated with a postoperative overall survival (OS) of 24.6 months and a cost of $3837/patient. Clinical evaluation and CA 19-9 assay every 6 months until recurrence was associated with a 32.8-month OS and a cost of $7496/patient, with an incremental cost-effectiveness ratio (ICER) of $5364/life-year (LY). Additional routine imaging every 6 months incrementally increased total cost by $3465 without increasing OS. ICERs associated with clinic visits every 3 months without/with routine imaging were $127,680 and $294,696/LY, respectively. Sensitivity analyses changed the strategies’ absolute costs but not the relative ranks of their ICERs.

Conclusions

Increasing the frequency and intensity of postoperative surveillance of patients after curative therapy for pancreatic cancer beyond clinical evaluation and CA 19-9 testing every 6 months increases cost but confers no clinically significant survival benefit.  相似文献   
43.
BackgroundIn this report, we describe our preliminary clinical results of arthroscopic Bankart repair in traumatic anterior-inferior shoulder instability using the two-portal method.MethodFrom August 2009 to December 2011, arthroscopic repair of Bankart lesion using this method was performed in 16 consecutive patients who were prospectively enrolled. Fifteen shoulders were treated with two-anchor sutures and one was treated with three-anchor sutures. Twelve patients received metallic anchor screws and four patients received bioanchor screws. The assessments were performed using the Rowe score, the University of California at Los Angeles shoulder rating scale, the American Shoulder and Elbow Surgeons score, and the shoulder range of motion (ROM) deficit.ResultsWith an average follow-up period of 22.9 months, all shoulder scores improved after surgery (p < 0.001). The average ROM deficit of the operated shoulders was not significant as compared with the healthy side in forward elevation (p > 0.05), but was significant in external rotation (p < 0.05). All of the 16 shoulders remained stable (100%) after the arthroscopic repair surgery. All patients returned to their preinjury levels of daily activity without recurrent problems.ConclusionIn patients with traumatic anterior glenohumeral instability, arthroscopic Bankart repair with the two portal method can provide good results. It can be an alternative method of treating patients with Bankart lesion without associated major glenoid defect or rotator cuff lesion in traumatic anterior-inferior instability.  相似文献   
44.
Theories of agrammatism have been challenged by the discovery that agrammatic patients can make above - chance judgements of grammaticality. Chinese poses an interesting test of this phenomenon, because its grammar is so austere, with few obligatory features. An on - line grammaticality judgement task was conducted with normal and aphasic speakers of Chinese, using the small set of constructions that do permit judgements of grammaticality in this language. Broca's and Wernicke's aphasics showed similar patterns, with above - chance discrimination between grammatical and ungrammatical forms, suggesting once again that Broca's aphasics are not unique in the degree of sparing or impairment that they show in receptive grammar. However, even for young normals, false - negative rates were high. We conclude that there is some sensitivity to grammatical well - formedness in Chinese aphasics, but the effect is fragile for aphasics and probabilistic for normals, reflecting the peculiar status of grammaticality in this language.  相似文献   
45.
Cytogenetics represents the most valuable predictor for a poor outcome in patients with acute myeloid leukemia (AML), but it encompasses a heterogeneous patient population who might have diverse pathogenesis and clinical courses. In particular, the significance of complex chromosome aberrations within this cohort has seldom been addressed before. We analyzed 48 AML patients with adverse-risk cytogenetics in this study. The complex karyotype (three or more numerical/structural cytogenetic changes; 29 patients) was found to occur more frequently among the elderly than a noncomplex adverse karyotype (19 patients; median age, 71 vs. 48; P = 0.005). The patients' performance status was the sole independent factor determining the complete remission rate among patients receiving standard induction chemotherapy. On survival analysis, two factors independently predicted a longer overall survival: noncomplex karyotypes [vs. complex karyotypes, hazard ratio (HR) 0.434, 95% confidence interval (CI) 0.189-0.994, P = 0.048] and achievement of complete remission [(CR) vs. CR not reached, HR 0.170, 95% CI 0.051-0.572, P = 0.004)]. In conclusion, among AML patients with adverse cytogenetics, complex chromosomal aberrations occurred more frequently among the elderly and predicted a poor outcome. These patients should be considered as a unique entity and be separated from those with a noncomplex adverse cytogenetic change. Exploring the underlying mechanisms of leukemogenesis could improve the therapeutic outcome for this group of patients.  相似文献   
46.
We recently reported that low-grade mucosa-associated lymphoid tissue lymphoma (MALToma) and diffuse large B-cell lymphoma (DLBCL) with MALToma (DLBCL[MALT]) of stomach are equally responsive to H. pylori eradication therapy (HPET) and that H. pylori-independent status is closely associated with nuclear translocation of BCL10. However, co-existing MALToma and DLBCL components of gastric DLBCL(MALT) may respond differentially to HPET and the underlying mechanism remains unclear. Tumour tissue samples from 18 patients with microdissectable co-existing MALToma and DLBCL cells were studied. The clonality of lymphoma cells was examined by polymerase chain reaction-based amplification of the CDR3 region of the IgH gene and confirmed by DNA sequence analysis. BCL10 expression was determined by immunohistochemistry. Differential response of co-existing MALToma and DLBCL to HPET was defined as complete eradication of one component while the other component remained. Five (27.8%) of the 18 patients showed different IgH gene rearrangements in the two components and three (60%) of these five patients had differential response of MALToma and DLBCL to HPET. By contrast, 13 patients showed identical IgH gene rearrangements and only one (8%) of them had differential response of the two components to HPET (p = 0.044). Further, all four patients with differential response of MALToma and DLBCL to HPET showed nuclear expression of BCL10 in the H. pylori-independent component and cytoplasmic expression of BCL10 in the H. pylori-dependent component while the expression patterns of BCL10 were identical in both of these components in the 14 patients who had similar tumour response to HPET. We conclude that different clonality is a common reason for the differential response of co-existing MALToma and DLBCL of gastric DLBCL(MALT) to HPET and that immunohistochemical examination of BCL10 expression may help to identify the co-existence of these components.  相似文献   
47.
Recent studies showed that population substructure (PS) can have more complex impact on rare variant tests and that similarity‐based collapsing tests (e.g., SKAT) may suffer more severely by PS than burden‐based tests. In this work, we evaluate the performance of SKAT coupling with principal components (PC) or variance components (VC) based PS correction methods. We consider confounding effects caused by PS including stratified populations, admixed populations, and spatially distributed nongenetic risk; we investigate which types of variants (e.g., common, less frequent, rare, or all variants) should be used to effectively control for confounding effects. We found that (i) PC‐based methods can account for confounding effects in most scenarios except for admixture, although the number of sufficient PCs depends on the PS complexity and the type of variants used. (ii) PCs based on all variants (i.e., common + less frequent + rare) tend to require equal or fewer sufficient PCs and often achieve higher power than PCs based on other variant types. (iii) VC‐based methods can effectively adjust for confounding in all scenarios (even for admixture), though the type of variants should be used to construct VC may vary. (iv) VC based on all variants works consistently in all scenarios, though its power may be sometimes lower than VC based on other variant types. Given that the best‐performed method and which variants to use depend on the underlying unknown confounding mechanisms, a robust strategy is to perform SKAT analyses using VC‐based methods based on all variants.  相似文献   
48.
49.

Background

We previously described the clinical classification of patients with resectable pancreatic tumor anatomy but marginal performance status (PS) or reversible comorbidities as “borderline resectable type C” (BR-C). This study was designed to analyze the incidence and risk factors for post-pancreaticoduodenectomy (PD) morbidity/mortality in a multi-institutional cohort of BR-C patients.

Methods

Elective PDs were evaluated from the 2005-10 ACS-NSQIP database. BR-C was defined as age?≥?80, poor PS, weight loss?>?10 %, pulmonary disease, recent myocardial infarction/angina, stroke history, and/or preoperative sepsis. Variables associated with 30-day postoperative major complications (PMC) and mortality were analyzed.

Results

A total of 3,033/8,266 (36.7 %) patients were BR-C. BR-C patients were more likely to suffer PMC (31.3 vs. 26.2 %) and mortality (4.1 vs. 2.3 %). BR-C patients with PMC suffered 50 % higher mortality versus non-BR-C patients with PMC (11.5 vs. 7.7 %) (all p?<?0.001). For BR-C patients, multivariate analysis identified the following risk factors for PMC or mortality: albumin?<?3.5 g/dL, dyspnea, preoperative sepsis, age?≥?80, poor PS, anesthesia score?≥?4, and intraoperative transfusion?≥?4 units.

Conclusions

Nationwide, one third of patients undergoing PD are medically borderline. These BR-C patients are at higher risk for and less able to be rescued from PMC. Surgeons should identify and optimize comorbidities and utilize prehabilitation to address functional deficits before elective PD.  相似文献   
50.
ObjectivesTumor size measurement is critical for accurate tumor staging in patients with pancreatic ductal adenocarcinoma (PDAC). However, accurate tumor size measurement is challenging in patients who received neoadjuvant therapy before resection, due to treatment-induced fibrosis and tumor invasion beyond the grossly identified tumor area. In this study, we evaluated the correlation between the tumor size and tumor volume measured on post-therapy computed tomography (CT) scans and the pathological measurement. Also, we investigated the correlation between these measurements and clinicopathological parameters and survival.Materials and methodsRetrospectively, we evaluated 343 patients with PDAC who received neoadjuvant therapy, followed by pancreaticoduodenectomy and had pre-operative pancreatic protocol CT imaging. We measured the longest tumor diameter (RadL) and the radiological tumor volume (RadV) on the post-therapy CT scan, then we categorized RadL into four radiologic tumor stages (RTS) based on the current AJCC staging (8th edition) protocol and RadV based on the median. Pearson correlation or Spearman’s coefficient (δ), T-test and ANOVA was used to test the correlation between the radiological and pathological measurement. Chi-square analysis was used to test the correlation with the tumor pathological response, lymph-node metastasis and margin status and Kaplan-Meier and Cox-proportional hazard for survival analysis. P-value < 0.05 was considered significant.ResultsAs a continuous variable, RadL showed a positive linear correlation with the post-therapy pathologic tumor size in the overall patient population (Pearson correlation coefficient: 0.72, P < 0.001) and RadV (δ: 0.63, p < 0.0001). However, there was no correlation between RadL and pathologic tumor size in patients with ypT0 and those with pathologic tumor size of ≤1.0 cm. Post-therapy RTS and RadV group correlated with ypT stage, tumor response grades using either CAP or MDA grading system, distance of superior mesenteric artery margin and tumor recurrence/metastasis.ConclusionAlthough RadL tends to understage ypT in PDAC patients who had no radiologically detectable tumor or small tumors (RTS0 or RTS1), radiologic measurement of post-therapy tumor size may be used as a marker for the pathologic tumor staging and tumor response to neoadjuvant therapy.  相似文献   
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