• Journal of Gastric Cancer
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• 제11권1호
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• pp.46-54
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• 2011

Purpose: There are few studies that have focused on the predictors of recurrence after gastrectomy for gastric carcinoma. This study analyzed the patients who died of recurrent gastric carcinoma and we attempted to clarify the clinicopathologic factors that are associated with the timing of recurrence. Materials and Methods: From June 1992 to March 2009, 1,795 patients underwent curative gastric resection at the Department of Surgery, Hanyang University College of Medicine. Among them, 428 patients died and 311 of these patients who died of recurrent gastric carcinoma were enrolled in this study. The clinicopathologic findings were compared between the 72 patients who died within one year after curative gastrectomy (the early recurrence group) and the 92 patients who died 3 years after curative gastrectomy (the late recurrence group). Results: Compared with the late recurrence group, the early recurrence group showed an older age, a more advanced stage, a poorly differentiated type of cancer and a significantly higher tendency to have lymphatic invasion, vascular invasion and perineural invasion.Especially in the gastric cancer patients with a more advanced stage (stage III and IV), the early recurrence group was characterized by a significantly higher preoperative serum carcino embryonic antigen level, perineural invasion and a relatively small number of dissected lymph nodes. Conclusions: The clinicopathologic characteristics of recurrent gastric cancer are significantly different according to the stage of disease, and even in the same stage. For the early detection of recurrence after curative surgery, it is important to recognize the clinicopathological factors that foretell a high risk of recurrence. It is mandatory to make an individualized surveillance schedule according to the clinicopathologic factors.

• Archives of Plastic Surgery
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• 제39권5호
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• pp.518-521
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• 2012

Background Skin cancer is the most common malignant tumor in humans. Basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are the two most common types of skin cancers. When skin cancer is clinically suspected, preoperative biopsies are recommended for a definite diagnosis. However, despite a concern over potential increased risk of metastasis associated with mechanical manipulation, there have been few investigations into whether a preoperative biopsy affected the recurrence of BCC and SCC. Methods Primary BCC or SCC patients who underwent standard surgical excision from 1991 to 2010 were reviewed and a retrospective analysis was performed. Ultimately, 45 BCC patients and 54 SCC patients, who did not meet the exclusion criteria, were analyzed. To identify whether a preoperative biopsy affected the recurrence of BCC and SCC, the recurrence rates of each with and without biopsy were compared. Results Preoperative biopsy had no statistically significant effect on recurrence (BCC, P=0.8680; SCC, P=0.7520). Also, there was no statistical significance between the interval from initial biopsy to first operation and recurrence (BCC, P=0.2329; SCC, P=0.7140). Even though there was no statistical significance, the mean interval from the biopsy to the operation among the BCC patients who underwent preoperative biopsy was 9.2 months in those who had recurrence and 2.0 months in those who had no recurrence. Conclusions There was no statistically significant relationship between preoperative biopsy and recurrence of BCC and SCC. However, there was a tendency toward recurrence in patients with a longer interval between the biopsy and the corrective operation in BCC.

• Journal of Gastric Cancer
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• 제16권4호
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• pp.215-220
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• 2016

Purpose: This study aimed to evaluate the rate, patterns, and risk factors associated with tumor recurrence in patients with T1N0 gastric cancer. Materials and Methods: The medical records of 8,753 patients with pathological T1N0M0 gastric cancer who underwent gastrectomy between 1994 and 2014 at Sungkyunkwan University School of Medicine were examined. Results: Among the 8,753 patients, 95 patients (1.1%) experienced tumor recurrence; this included 31 remnant, 27 hematogenous, 9 lymph nodal, 5 peritoneal, and 23 multiple-site recurrences. When patients were divided into two groups according to the presence of tumor recurrence, the following characteristics were higher in the recurrence group than in the non-recurrence group: older age (${\geq}65years$), male gender, undifferentiated histology, submucosal invasion, and venous invasion. In multivariate analysis, older age, male gender, tumor depth (sm2 and sm3 invasion), and venous invasion were independent risk factors for tumor recurrence. The recurrence rates were 0.7% in patients with less than two risk factors, 1.7% in those with two risk factors, 3.0% in those with three risk factors, and 6.3% in those with four risk factors (P<0.001). Conclusions: Although tumor recurrence is rare in pT1N0M0 gastric cancer, some patients with certain risk factors demonstrate an increased rate of tumor recurrence. Careful follow-up is required for patients with three or four risk factors.

• Journal of Korean Neurosurgical Society
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• 제63권4호
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• pp.513-518
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• 2020

Objective : Chronic subdural hematoma (CSDH) is one of the most common intracranial hemorrhages. It can be managed with a simple surgical treatment such as burr-hole trephination and drainage. However, it has a relatively high recurrence rate. The mechanisms and risk factors for the recurrence have not yet been clearly identified and studies have reported varying results. Methods : We analyzed 230 patients with CSDH who were treated with burr-hole trephination and drainage at our institution from March 2011 to March 2016. The patients were divided into recurrence and non-recurrence groups and the medical records of each group were used to analyze the risk factors associated with CSDH recurrence. Results : After burr-hole trephination and drainage, CSDH recurrence was observed in 49 (21.3%) of the 230 patients. In univariate analysis, none of the factors showed statistical significance with respect to CSDH recurrence. In multivariate analysis, preoperative antithrombotic medication was the only independent risk factor for CSDH recurrence (odds ratio, 2.407; 95% confidence interval, 1.047-5.531). Conclusion : The present study found that preoperative antithrombotic medication was independently associated with CSDH recurrence.

• Journal of Gastric Cancer
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• 제12권2호
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• pp.88-98
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• 2012

Purpose: Local recurrence, due to residual tumor, may occur after endoscopic resection for early gastric cancer. The aims of this study are to evaluate the predictive factors for local recurrence, and suggest an appropriate follow-up biopsy strategy. Materials and Methods: We retrospectively reviewed 396 early gastric cancers from 372 consecutive patients, who underwent endoscopic resection between January 2002 and April 2008. Cumulative recurrence rates were determined by the Kaplan-Meier method, and Cox proportional hazard analysis was used to determine the risk factors for local recurrence. Results: Local recurrence at the endoscopic resection site was found in 17 cases, among the total 396 lesions, during a median follow-up period of 48 months. The 5-year cumulative local recurrence rate was 4.8%. Multivariate analyses determined that tumor involvement at the lateral resection margin [hazard ratio: 35.9; P<0.001], uncheckable lateral resection margin [hazard ratio: 16.8; P<0.001], uncheckable or involved deep resection margin [hazard ratio: 3.76; P=0.047], and piecemeal resection [hazard ratio: 3.95; P=0.007] were associated with local recurrence. If a lesion was positive for any of these risk factors, the 5-year cumulative recurrence rate was 27.0%, while local recurrence was not found in any lesion that lacked these risk factors. Most episodes of recurrence were found during the first or second follow-up endoscopic biopsy at the ulcer scar. Conclusions: Routine follow-up biopsies at the endoscopic resection site might be unnecessary in cases where an early gastric cancer lesion was endoscopically resected en bloc with tumor-free lateral and deep margins.

• Journal of Gastric Cancer
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• 제10권3호
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• pp.106-110
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• 2010

Purpose: The purpose of this study was to analyze the clinical courses of patients with gastric cancer and positive resection margins after a gastrectomy for gastric cancer who did not undergo subsequent surgery. Materials and Methods: Among 4,452 patients who underwent surgery for gastric cancer from January 2001 to December 2007, 20 patients with positive resection margins after gastrectomy for gastric cancer who did not undergo subsequent surgery were included. The recurrence patterns were confirmed by postoperative computed tomography and gastroscopy, which were performed on a planned schedule. All recurrence patterns after gastrectomy were classified as loco-regional, peritoneal, or distant metastases. Results: The patients with confirmed recurrence all had advanced stage cancer (III-IV), and the recurrence sites were variable. However, peritoneal and distant recurrences were more common than loco-regional recurrences. The patients with loco-regional recurrence also had peritoneal and/or distant recurrence. Conclusions: Patients with gastric cancer and a positive resection margin showed more frequent peritoneal and distant metastases than loco-regional recurrence. In addition, patients with loco-regional recurrence also had peritoneal and distant recurrence. A positive resection margin of gastric cancer was related with poor histological differentiation, diffuse type, and advanced stage (III-IV).

• Advances in pediatric surgery
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• 제9권1호
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• pp.24-29
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• 2003

To evaluate the clinical findings of the recurrent intussusception, 351 patients with 445 intussusceptions were reviewed. Recurrence rate, pattern of recurrence, reducibility, pathologic lead points (PLP), and operative findings and long term follow up of the multiple recurrences were analyzed. Of 351 patients, 303 had no recurrence, 26 had one recurrence, and 22 had multiple recurrences. Over all recurrence rate was 16.4% ; 18.5% were managed by air reduction, 16.2% by barium reduction and 5.9% by operation. Eleven PLPs were proved operatively and an additional 6 suspected PLPs were depicted radiologically. The most frequent PLP was ileal lymphoid hyperplasia. Intervals between reduction and recurrence were less than 2 weeks in 31 cases, between 2 weeks and 1 year in 55, and more than 1 year in 8. The longest interval was 2 years and 4 months.

• 대한수학회지
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• 제42권4호
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• pp.673-693
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• 2005

In this paper, we first find a necessary and sufficient condition for the existence of multiple orthogonal polynomials by the moments of a pair of measures $(d{\mu},\;dv)$ and then give representations for multiple orthogonal polynomials. We also prove four term recurrence relations for multiple orthogonal polynomials of type II and several interesting relations for multiple orthogonal polynomials are given. A generalized recurrence relation for multiple orthogonal polynomials of type I is found and then four term recurrence relations are obtained as a special case.

• 대한수학회보
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• 제56권6호
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• pp.1577-1588
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• 2019

We show a multiple recurrence theorem for topological dynamical systems with countable directed partial semigroup actions, which generalizes the well-know IP-version of multiple recurrence theorem proved by Furstenberg and Weiss.

• Asian Pacific Journal of Cancer Prevention
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• 제15권14호
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• pp.5539-5544
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• 2014

Background: To evaluate the location of tumor relapse and imaging modality for detection according to the breast cancer subtype: luminal A, luminal B, HER2 positive luminal B, nonluminal HER2 positive, and triple negative. Materials and Methods: A total of 1244 patients with breast cancer with known estrogen receptor (ER), progesterone receptor (PR), Ki-67 and human epidermal growth factor receptor 2 (HER2), who underwent breast surgery from 2009 to 2012 were analyzed. Patients were classified into the following categories: luminal A (n=458), luminal B (n=241), HER2 positive luminal B (n=227), nonluminal HER2 positive (n=145) and triple negative (n=173). A total of 105 cases of relapse were detected in 102 patients: locoregional recurrence (n=46), recurrence in the contralateral breast (n=28) and distant metastasis (n=31). Comparison of proportions was used to determine the difference between subtypes. Results: Relapse rates by subtypes are as follows: luminal A 23 of 458 (5.02%), luminal B 19 of 241(7.88%), HER2 positive luminal B 15 of 227 (6.61%), nonluminal HER2 postive 19 of 145 (13.10%) and triple negative 29 of 173(16.76%). Luminal A tumors had the lowest rate of recurrence and had significantly lower recurrence rate in comparison with nonluminal HER2 postive (p=0.0017) and triple negative subtypes (p<0.0001). Compared with all other subtypes except nonluminal HER2 positive, triple negative tumors had the highest rate of tumor recurrence (p<0.01). Triple negatives were most likely to develop contralateral recurrence against all subtypes (p<0.05). Detection rate of locoregional and contralateral tumor recurrence were 28.3% on mammography (n=17/60). Conclusions: Luminal A tumors are associated with a low risk of recurrence while triple negative lesions have a high risk. In case of triple negative tumors, the contralateral breast has much more recurrence as compared with all other subtype. In terms of detection rates, breast USG was the best modality for detecting tumor recurrence, compared with other modalities (p<0.05). Subtyping of breast tumors using a molecular gene expression panel can identify patients who have increased risk of recurrence and allow prediction of locations of tumor recurrence for each subtype.