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991.

Background

We evaluated the prevalence of coexisting asymptomatic colorectal neoplasm (CRN) in patients with gastric cancer (GC).

Methods

Preoperative colonoscopic examinations were performed in 495 patients with GC who underwent gastrectomy between January 2009 and December 2010. To compare the prevalence of CRN in these patients with that in a normal population, we selected 495 sex- and age-matched persons who underwent colonoscopies for health screening. Risk factors for CRN were evaluated by univariate and multivariate analyses.

Results

The overall incidence of CRN was 41.8 % (414/990). The prevalence of overall CRN, high-risk CRN, and colorectal carcinoma (CRC) were significantly higher in the GC group than in the control group (overall CRN: 48.9 % vs. 34.7 %; high-risk CRN: 28.3 % vs. 13.5 %; CRC: 2.6 % vs. 0.2 %; all P < 0.001). The presence of GC [odds ratio (OR), 1.82; 95 % confidence interval (CI), 1.4–2.38; P < 0.001], age ≥50 years (OR, 2.58; 95 % CI, 1.75–3.81; P < 0.001), and male sex (OR, 2.28; 95 % CI, 1.72–3.02; P < 0.001) were risk factors for overall CRN. In patients with GC, age ≥40 years (OR, 3.22; 95 % CI, 1.24–8.37; P = 0.016) and male sex (OR, 3.21; 95 % CI, 2.17–4.76; P < 0.001) were risk factors for overall CRN.

Conclusions

The prevalence of coexisting CRN, including CRC, was higher in patients with GC than in the normal population. Preoperative colonoscopy is strongly indicated in patients with GC who are male and/or ≥40 years of age.  相似文献   
992.
Right hepatectomy with the middle hepatic vein (MHV) affects venous return and function of the remaining liver. We compared the remnant liver volume in the donors of resection with or without the MHV on the remnant liver volume regeneration. Living donors who had undergone right hepatectomy without MHV (RH group; n = 36) and those with MHV (ERH group; n = 19) were reviewed. Volume regeneration of segments I-III, segment IV, and total remnant liver volume was assessed at postoperative day (POD) 7 and 30 using a computed tomography-based volumetry program. According to the measured volume data, we calculated the liver remnant volume and the rate of liver remnant volume increase. The regeneration rate of segment IV was significantly low in the ERH group compared with that in the RH group at POD 7 and POD 30 (160% vs 141%; P = .018 and 189% vs 154%; P = .007). In contrast, the regeneration rate of the total remnant liver volume was not significantly different between the 2 groups (173% vs 175%; P = .758 and 199% vs 198%; P = .880). In conclusion, extended right hepatectomy can be safely performed with careful preoperative evaluation without significant impairment of remnant liver regeneration.  相似文献   
993.
BACKGROUND: Iron deficiency results in altered gallbladder and sphincter of Oddi (SO) motility and cholesterol crystal formation. In addition, gallbladder neuronal nitric oxide synthase (nNOS) has been shown to be markedly reduced after 8 weeks on an iron-deficient diet. However, the effects of prolonged iron deficiency on gallbladder and SO nNOS as well as crystal formation have not been determined. Therefore, we tested the hypothesis that iron deficiency would downregulate both gallbladder and SO nNOS expression and that nNOS downregulation and cholesterol crystal formation would progress over time. MATERIALS AND METHODS: Thirty-eight adult female prairie dogs were fed either an ironsupplemented (Fe+) (200 ppm) or an iron-deficient (Fe-) (8 ppm) diet for 8 weeks (Fe+ n = 9, Fe- n = 10) or 16 weeks (Fe+ n = 9, Fe- n = 10). Blood hemoglobin (HbG) was measured; gallbladder cholesterol crystals were counted; and cholesterol saturation indices (CSI) were calculated. Gallbladder and SO nNOS levels were measured by Western blot. RESULTS: The Fe+ prairie dogs had significantly higher HbG than the Fe- animals (16.9 +/- 0.6 g/dl vs 15.2 +/- 0.5 g/dl, respectively, P < 0.05) after 8 weeks. This difference was even greater after 16 weeks (16.1 +/- 0.4 g/dl vs 14.0 +/- 0.5 g/dl, P < 0.01). At 8 weeks, more cholesterol crystals per 10 HPF were observed in the Fe- animals (0.4 +/- 0.3 vs 1.6 +/- 0.4 per 10 HPF, P < 0.05). This difference was even greater after 16 weeks (0.0 +/- 0.0 vs 52.6 +/- 25.3 per 10 HPF, P < 0.01). No difference in the CSI was observed in the four groups. Iron deficiency decreased the nNOS/beta-actin protein levels in the gallbladder and SO at 8 weeks (57.0 +/- 29.6 vs 7.4 +/- 2.6, gallbladder, P < 0.05) (98.4 +/- 39.7 vs 29.9 +/- 11.0, SO, P = 0.09), but these levels returned to baseline at 16 weeks. CONCLUSIONS: We conclude that iron deficiency acutely suppresses gallbladder and SO nNOS, and that compensatory mechanisms return nNOS to baseline levels while cholesterol crystal formation increases over time.  相似文献   
994.

Background

The prognosis of patients with positive surgical resection margins is dismal in gastric cancer. However, the influence of positive margin itself on prognosis is still uncertain, especially in advanced gastric cancer (AGC). The aims of the present study were to evaluate the prognostic impact of microscopic tumor involved resection margins in stage III–IV AGC after gastric resection in comparison with other well-known factors.

Methods

Among 1,536 consecutive gastric cancer patients who received intentional curative resection for stage III–IV AGC between April 2001 and December 2011 at the National Cancer Center, 35 patients (2.28 %) had positive resection margins on their final histology. A comparison of clinicopathologic characteristics, recurrence pattern, overall survival (OS), and disease-free survival (DFS) was made between positive margin (PM) patients and negative margin (NM) patients.

Results

Among the 35 PM patients, 15 (42.9 %) had proximal involved margins, 21 (60.0 %) had distal involved margins, and one (2.9 %) had both involved margins. Twenty-eight PM patients (80.0 %) were stage III, and 7 (20.0 %) were stage IV. Recurrence was significantly higher in PM than NM (63.6 % vs. 39.7 %, respectively; p = 0.005). The OS and DFS rates were significantly lower in the PM group than in the NM group (14.9 vs. 36.3 months, p < 0.001 and 11.6 vs. 27.1 months, p = 0.005, respectively). The presence of PM was an independent risk factor for both OS and DFS.

Conclusions

The presence of PM is an independent risk factor for OS and DFS. Considering the prognostic impact of PM, a sufficient resection margin should be ensured when determining the resection line in gastrectomy with curative intent. The reoperation to secure clear resection margins should be considered as a treatment of choice in the case of PM.  相似文献   
995.

Background  

Lymph node metastases occur frequently in patients with papillary thyroid carcinoma (PTC), and the central compartment of the neck is the most frequently involved site. Some authors advocate prophylactic central neck dissection (CND) during total thyroidectomy. However, little is known about the effects of prophylactic unilateral CND in papillary thyroid microcarcinoma (PTMC) patients who undergo hemithyroidectomy. This study was designed to investigate the impact of prophylactic unilateral CND in this population.  相似文献   
996.
BACKGROUND: Serum protein profiling patterns can reflect the pathological state of a patient and therefore may be useful for clinical diagnostics. Here, we present results from a pilot study of proteomic expression patterns in hemodialysis patients designed to evaluate the range of serum proteomic alterations in this population. METHODS: Surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS) was used to analyze serum obtained from patients on periodic hemodialysis treatment and healthy controls. Serum samples from patients and controls were first fractionated into six eluants on a strong anion exchange column, followed by application to four array chemistries representing cation exchange, anion exchange, metal affinity and hydrophobic surfaces. A total of 144 SELDI-TOF-MS spectra were obtained from each serum sample. RESULTS: The overall profiles of the patient and control samples were consistent and reproducible. However, 30 well-defined protein differences were observed; 15 proteins were elevated and 15 were decreased in patients compared to controls. Serum from 1 patient exhibited novel protein peaks suggesting possible additional changes due to a secondary disease process. CONCLUSION: SELDI-TOF-MS demonstrated consistent serum protein profile differences between patients and controls. Similarity in protein profiles among dialysis patients suggests that patient physiological responses to end-stage renal disease and/or dialysis therapy have a major effect on serum protein profiles.  相似文献   
997.

Background

Depth of tumor invasion is an important prognostic factor for gallbladder cancer. The aim of this study was to investigate the clinicopathological prognostic factors of T2 gallbladder cancer.

Methods

We retrospectively reviewed the clinicopathological data and survival for 83 patients with T2 gallbladder cancers who underwent surgical resection between January 1995 and December 2007.

Results

The overall survival rates were 48.9% at 3 years and 29.3% at 5 years. Univariate analysis revealed that R0 resection (P?<?0.001), extended surgery (P?=?0.028), lymph node dissection (P?=?0.024), non-infiltrative tumors (P?=?0.001), well differentiation (P?=?0.001), absence of lymphatic (P?=?0.025), perineural (P?=?0.001), and vascular (P?=?0.025) invasion, absence of lymph node metastasis (P?=?0.001), negative resection margin (P?=?0.016), and stage (P?=?0.002) were significantly better predictors for survival. A significant difference in survival between Rx and R1 was not found. R0 resection, lymph node dissection, well differentiation, and absence of perineural and vascular invasion were significantly independent prognostic factors for overall survival. Recurrence occurred in 48 patients (57.8%). Age older than 65 years, R0 resection, non-infiltrative tumors, and good differentiation were significant independent predictors of disease-free survival by multivariate analysis.

Conclusions

For T2 tumors, radical surgery including lymph node dissection should be performed to achieve R0 resection. Tumors with infiltrative types and suspicious lymph node metastasis in the intraoperative findings were candidates for aggressive surgical management to improve patient survival.  相似文献   
998.

Background

Various techniques for endoscopic thyroidectomy have been introduced in the past decade, and the cosmetic superiority of these techniques has been universally acknowledged. We developed the endoscopic thyroidectomy via bilateral axillo-breast approach (BABA) and have performed more than 500 operations. The aims of this study are to analyze the surgical outcomes and to evaluate the effectiveness and safety of BABA endoscopic thyroidectomy.

Patients and methods

Between February 2004 and March 2008, 512 patients with thyroid diseases underwent BABA endoscopic thyroidectomy. The criteria analyzed were clinicopathologic characteristics, types of operation, operation time, tumor–node–metastasis (TNM) stage on the basis of the 7th edition of the American Joint Committee on Cancer (AJCC), results after radioactive ablation therapy, and recurrence of disease in these patients.

Results

Of 512 patients, 397 had a malignant tumor and 115 had benign thyroid disease. Eight patients were diagnosed with Graves’ disease, and nine patients underwent completion thyroidectomy. Three cases were subjected to open thyroidectomy due to uncontrolled bleeding. Mean operation time was 151.2?±?38.1?min for total and near-total thyroidectomy, and 141.7?±?50.1?min for subtotal thyroidectomy and lobectomy. Regarding postoperative complications, transient hypocalcemia occurred in 31.1% of patients and permanent hypoparathyroidism occurred in 4.2% of patients. Transient hoarseness occurred in 20.3% of patients, and permanent vocal cord palsy occurred in 1.7%. Mean hospital stay after operation was 3.34?±?0.8?days (range 3–7?days), and mean follow-up period was 57.1?±?17.6?months (range 38.5–71.7?months). There were eight cases of recurrent thyroid carcinoma, and no mortality has occurred up to the present time.

Conclusions

Endoscopic thyroidectomy via bilateral axillo-breast approach is a safe and effective method that gives good surgical completeness, a low rate of postoperative complications and recurrence, and an excellent cosmetic result. Therefore, this method is a good choice for patients with surgical thyroid diseases.  相似文献   
999.
1000.
Background The objectives of this study were to investigate the clinicopathological features of branch intraductal papillary mucinous neoplasm (IPMN) and to determine safe criteria for its observation. Most clinicians agree that surgical resection is required to treat main duct-type IPMN because of its high malignancy rate. However, no definite treatment guideline (with respect to surgery or observation) has been issued on the management of branch duct type IPMN. Methods We retrospectively reviewed the clinicopathological data of 138 patients who underwent operations for IPMN between 1993 and 2006 at five institutes in Korea. Results Of 138 patients (mean age, 60.6 years; 87 men, 51 women), 76 underwent pancreatoduodenectomy, 39 distal pancreatectomy, 4 total pancreatectomy, and 20 limited pancreatic resection. There were 112 benign cases: 47 adenoma, 63 borderline cases, and 26 malignant cases, with 9 of these being noninvasive and 17 invasive. By univariate analysis, tumor size and the presence of a mural nodule were identified as meaningful predictors of malignancy. By receiver operating characteristic curve analysis, a tumor size of >2 cm was found to be the most valuable predictor of malignancy. When cases were classified according to tumor size and the presence of a mural nodule, the malignancy rate for a tumor ≤2 cm without a mural nodule was 9.2%, for a tumor of ≤2 cm plus a mural nodule was 25%, and for other conditions such as tumor >2 cm, >25%. Conclusions Many branch duct IPMNs are malignant. Surgical treatment is recommended, except in cases that are strongly suspected to be benign or cases that present a high operative risk. Observation is only recommended in patients with a tumor size of ≤2 cm without a mural nodule.  相似文献   
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