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21.

Background

The molecular alterations that drive tumorigenesis in intrahepatic cholangiocarcinoma (ICC) remain poorly defined. We sought to determine the incidence and prognostic significance of mutations associated with ICC among patients undergoing surgical resection.

Methods

Multiplexed mutational profiling was performed using nucleic acids that were extracted from 200 resected ICC tumor specimens from 7 centers. The frequency of mutations was ascertained and the effect on outcome was determined.

Results

The majority of patients (61.5 %) had no genetic mutation identified. Among the 77 patients (38.5 %) with a genetic mutation, only a small number of gene mutations were identified with a frequency of >5 %: IDH1 (15.5 %) and KRAS (8.6 %). Other genetic mutations were identified in very low frequency: BRAF (4.9 %), IDH2 (4.5 %), PIK3CA (4.3 %), NRAS (3.1 %), TP53 (2.5 %), MAP2K1 (1.9 %), CTNNB1 (0.6 %), and PTEN (0.6 %). Among patients with an IDH1-mutant tumor, approximately 7 % were associated with a concurrent PIK3CA gene mutation or a mutation in MAP2K1 (4 %). No concurrent mutations in IDH1 and KRAS were noted. Compared with ICC tumors that had no identified mutation, IDH1-mutant tumors were more often bilateral (odds ratio 2.75), while KRAS-mutant tumors were more likely to be associated with R1 margin (odds ratio 6.51) (both P < 0.05). Although clinicopathological features such as tumor number and nodal status were associated with survival, no specific mutation was associated with prognosis.

Conclusions

Most somatic mutations in resected ICC tissue are found at low frequency, supporting a need for broad-based mutational profiling in these patients. IDH1 and KRAS were the most common mutations noted. Although certain mutations were associated with ICC clinicopathological features, mutational status did not seemingly affect long-term prognosis.  相似文献   
22.
23.
CALLA-positive myeloma: an aggressive subtype with poor survival   总被引:5,自引:0,他引:5  
Durie  BG; Grogan  TM 《Blood》1985,66(1):229-232
Detailed immunotyping was carried out on 21 direct myeloma bone marrow aspirates and eight human myeloma cell lines. Four previously untreated common acute lymphoblastic leukemia antigen (CALLA)-positive myeloma patients were identified and six of eight cell lines (75%) were also positive. CALLA positivity, as part of an immature B phenotype, was found to correlate with very aggressive clinical disease: median survival six months v 56 months for the CALLA-negative group.  相似文献   
24.
Background  There are limited data on patterns of recurrence and factors associated with local recurrence following pancreaticoduodenectomy for pancreatic adenocarcinoma and adjuvant 5-flurouracil-based chemoradiation therapy. Methods and Materials  Between 1995 and 2005, 905 patients underwent pancreaticoduodenectomy for pancreatic adenocarcinoma; 154 patients had complete pattern of recurrence data available. Results  At median follow-up of 20.2 months, 103 (66.9%) patients recurred with median time to recurrence of 16.2 months. Most patients recurred with distant disease only (68.9%), while 21.4% patients recurred with local disease only; ten (9.7%) patients recurred with local and distant disease. Several factors were associated with local recurrence: poor tumor differentiation (hazards ration [HR] 2.39) and presence of metastatic lymph nodes (HR 1.89, both p < 0.05). Among N1 patients, poor tumor differentiation (HR 3.92), >5 metastatic LN (HR 3.75), and lymph node ratio (LNR) >0.4 (HR 2.96) had the highest risk of local recurrence (all p < 0.05). Increasing LNR was associated with an incremental increased risk of local recurrence (LNR <0.2, 21.3% versus LNR ≥0.2 to 0.4, 25.2% versus LNR >0.4, 40.4%; p < 0.05). Conclusions  Although most patients who receive standard 5-flurouracil-based chemoradiation therapy will ultimately succumb to distant disease, about 30% recur locally. Poor tumor differentiation, a high number of metastatic LN (>5), and LNR >0.4 are associated with the highest risk of local failure. In these patients, radiation dose escalation and/or a combination of radiation with novel chemotherapeutic agents may be necessary to improve outcomes. Presented at the American Hepato-Pancreato-Biliary Association Annual Meeting, Ft. Lauderdale, Florida, March 29th, 2008  相似文献   
25.
26.

Background

Delta hemoglobin (ΔHb) is defined as the difference between the preoperative Hb and the lowest post-operative Hb level. We sought to define the impact of ΔHb relative to nadir Hb levels on the likelihood of transfusion, as well as characterize the impact of ΔHb and nadir Hb on morbidity among a large cohort of patients undergoing complex hepatopancreatobiliary (HPB) surgery.

Methods

Patients who underwent pancreatic or hepatic resection between January 1, 2009 and June 30, 2015 at Johns Hopkins Hospital were identified. Data on the perioperative ΔHb, nadir Hb, as well as blood utilization were obtained and analyzed. Multivariable logistic regression models were used to identify the factors associated with ΔHb and the impact of ΔHb on perioperative morbidity. A Bayesian model was used to evaluate the correlation of ΔHb and nadir Hb with the likelihood of transfusion, as well as the impact on morbidity.

Results

A total of 4363 patients who underwent hepatobiliary (n?=?2200, 50.4 %) or pancreatic (n?=?2163, 49.6 %) surgery were identified. More than one quarter of patients received at least one unit of packed red blood cells (PRBC) (n?=?1187, 27.2 %). The median nadir Hb was 9.2 (IQR 7.9–10.5)?g/dL resulting in an average ΔHb of 3.4 mg/dL (IQR 2.2–4.7) corresponding to 26.3 %. Both ΔHb and nadir Hb strongly influenced provider behavior with regards to use of transfusion. Among patients with the same nadir Hb, ΔHb was strongly associated with use of transfusion; among patients who had a nadir Hb ≤6 g/dL, the use of transfusion was only 17.9 % when the ΔHb?=?10 % versus 49.1 and 80.9 % when the ΔHb was 30 or 50 %, respectively. Perioperative complications occurred in 584 patients (13.4 %) and were more common among patients with a higher value of ΔHb, as well as patients who received PRBC (both P?<?0.001).

Conclusions

The combination of the Hb trigger with ΔHb was associated with transfusion practices among providers. Larger ΔHb values, as well as receipt of transfusion, were strongly associated with risk of perioperative complication following HPB surgery.
  相似文献   
27.

Background

This study utilized a multi-institutional database to evaluate risk factors for readmission in patients undergoing curative gastrectomy for gastric adenocarcinoma with the intent of describing both perioperative risk factors and the relationship of readmission to survival.

Methods

Patients who underwent curative resection of gastric adenocarcinoma from 2000 to 2012 from seven academic institutions of the US Gastric Cancer Collaborative were analyzed. In-hospital deaths and palliative surgeries were excluded, and readmission was defined as within 30 days of discharge. Univariate and multivariable logistic regression analyses were employed and survival analysis conducted.

Results

Of the 855 patients, 121 patients (14.2 %) were readmitted. Univariate analysis identified advanced age (p?<?0.0128), American Society of Anesthesiology status ≥3 (p?=?0.0045), preexisting cardiac disease (p?<?0.0001), hypertension (p?=?0.0142), history of smoking (p?=?0.0254), increased preoperative blood urea nitrogen (BUN; p?=?0.0426), concomitant pancreatectomy (p?=?0.0056), increased operation time (p?=?0.0384), estimated blood loss (p?=?0.0196), 25th percentile length of stay (<7 days, p?=?0.0166), 75th percentile length of stay (>12 days, p?=?0.0256), postoperative complication (p?<?0.0001), and total gastrectomy (p?=?0.0167) as risk factors for readmission. Multivariable analysis identified cardiac disease (odds ratio (OR) 2.4, 95 % confidence interval (CI) 1.6–3.3, p?<?0.0001), postoperative complication (OR 2.3, 95 % CI 1.6–5.4, p?<?0.0001), and pancreatectomy (OR 2.2, 95 % CI 1.1–4.1, p?=?0.0202) as independent risk factors for readmission. There was an association of decreased overall median survival in readmitted patients (39 months for readmitted vs. 103 months for non-readmitted). This was due to decreased survival in readmitted stage 1 (p?=?0.0039), while there was no difference in survival for other stages. Stage I readmitted patients had a higher incidence of cardiac disease than stage I non-readmitted patients (58 vs. 24 %, respectively, p?=?0.0002).

Conclusions

Within this multi-institutional study investigating readmission in patients undergoing curative resection for gastric cancer, cardiac disease, postoperative complication, and concomitant pancreatectomy were identified as significant risk factors for readmission. Readmission was associated with decreased overall median survival, but on further analysis, this was driven by differences in survival for stage I disease only.
  相似文献   
28.
Background The role of surgical resection in patients with large or multinodular hepatocellular carcinoma (HCC) remains unclear. This study evaluated the long-term outcome of patients with hepatic resection for large (>5 cm in diameter) or multinodular (more than three nodules) HCC by using a multi-institutional database.Methods The perioperative and long-term outcomes of 404 patients with small HCC (<5 cm in diameter; group 1) were compared with those of 380 patients with large or multinodular HCC (group 2). The prognostic factors in the latter group were analyzed.Results The postoperative complication rate (27% vs. 23%; P = .16) and hospital mortality rate (2.4% vs. 2.7%; P = .82) were similar between groups. The overall survival rates were significantly higher in group 1 than group 2 (1 year, 88% vs. 74%; 3 years, 76% vs. 50%; 5 years, 58% vs. 39%; P < .001). Among patients in group 2, five independent prognostic factors were identified to be associated with a worse overall survival: namely, symptomatic disease, presence of cirrhosis, multinodular tumor, microvascular tumor invasion, and positive histological margin.Conclusions Hepatic resection can be safely performed in patients with large or multinodular HCC, with an overall 5-year survival rate of 39%. Symptomatic disease, the presence of cirrhosis, a multinodular tumor, microvascular invasion, and a positive histological margin are independently associated with a less favorable survival outcome.  相似文献   
29.
We have used the long-term bone marrow culture (LTBMC) system to analyze hematopoiesis in three patients with dyskeratosis congenita (DC), two of whom had aplastic anemia, and the third had a normal blood count (apart from mild macrocytosis) and normal BM cellularity. Hematopoiesis was severely defective in all three patients, as measured by a low incidence of colony-forming cells and a low level of hematopoiesis in LTBMC. The function of the marrow stroma was normal in its ability to support the growth of hematopoietic progenitors from normal marrows seeded onto them in all three cases, but the generation of hematopoietic progenitors from patients marrow cells inoculated onto normal stromas was reduced, thus suggesting the defect to be of stem cell origin. The parents and unaffected brother of one of the families have also been studied in LTBMC and all showed normal hematopoietic and stromal cell function. From this study we speculate that there are some similarities between DC and the defect in the W/Wv mouse.  相似文献   
30.
In five conscious dogs with chronic gastric fistulas we studied the effect of somatostatin solutions on pentagastrin-stimulated acid secretion. Somatostatin was dissolved in 0.154 M NaCl alone or in the same amount of saline to which dog albumin had been added to give a 0.5% solution. Somatostatin produced a dose-dependent inhibition of pentagastrin-stimulated gastric secretion. However, the inhibition was significantly less when somatostatin was dissolved in saline as compared to saline plus albumin. This study suggests that albumin should be added to somatostatin solutions to preserve biological activity, and it confirms previous reports indicating that, without albumin, basic peptides have a tendency to stick to infusion systems.  相似文献   
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