• Journal of Gastric Cancer
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• v.1 no.2
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• pp.106-112
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• 2001

Purpose: Even with excellent surgical outcome, recurrence of early gastric cancer (EGC) after a curative resection is not declining because the incidence of EGC is increasing. The aim of this study was to propose an appropriate treatment strategy by assessing the risk factors for recurrence of curatively resected early gastric cancer. Materials and Methods: Of 3662 patients who had undergone gastric resections for gastric cancer from 1987 to 1996, the cases of 1050 curatively resected EGC patients were reviewed retrospectively. Among those 1050 patients, 50 patients ($4.8\%$) were diagnosed as having recurrent cancer, which was confirmed by clinico-radiological examination or re-operation. The risk factors that determined the recurrence patterns were investigated by using univariate and multivariate analyses. Results: The mean time to recurrence was 30.9 months, and hematogenous recurrence was the most frequent type ($32.0\%$). Among the 50 recurred patients, peritoneal recurrence showed the shortest mean time to recurrence ($18.5\pm17.7$months). Between the recurred and the non-recurred patients, there was no statistically significant difference with respect to age, sex, operation type, tumor size, tumor location, gross appearance, or histological differentiation. However, depth of invasion (submucosal invasion) and nodal involvement were significantly different (P<0.001) between the two groups. Using logistic regression analyses, nodal involvement was the only significant risk factor for recurrence in early gastric cancer (P<0.001). The median survival after the recurrence had been diagnosed was 4 months. Conclusion: Although the prognosis for EGC patients is excellent and recurrence of EGC after a curative resection is rare, the time to recurrence and the patterns of recurrence in EGC patients were diverse and unpredictable, and the result after recurrence is dismal. Considering the impact of lymph node metastasis on recurrence of EGC, a systematic lymphadenectomy, rather than limited surgery, should be performed if lymph node involvement is confirmed pre- or intraoperatively. Also if the postoperative pathologic findings reveal lymph node involvement, adjuvant chemotherapy is recommended.

• Journal of Chest Surgery
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• v.47 no.3
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• pp.269-274
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• 2014

Background: The purpose of this study was to evaluate the outcome of reoperation with curative intent for the treatment of anastomotic recurrent gastric cancer. Methods: Ten patients with anastomotic recurrence of gastric cancer who underwent reoperation from November 1995 to February 2011 were analyzed retrospectively. The time interval between the first operation and reoperation, recurrence pattern, type of surgery, survival, and postoperative outcome were analyzed. Results: The average time to recurrence after initial surgery was 48.8 months (median, 23.5 months). Of the ten patients, eight (80.0%) had recurrence at the esophagojejunostomy, one (10.0 %) at the esophagogastrostomy, and two (20.0%) at the esophagus. Among these patients, five had combined metastasis or invasion to major organs in addition to anastomotic recurrence. Complete resection was achieved in five patients (50.0%), and incomplete resection or bypass surgery was performed in the remaining five patients (50.0%). The overall median survival time was 7.0 months (range, 2.2 to 105.5 months). The median survival time following complete resection and palliative surgery (incomplete resection or bypass surgery) was 28.1 months (range, 4.2 to 105.5 months) and 5.5 months (range, 2.2 to 7.5 months), respectively. Conclusion: Surgical resection of anastomotic recurrent gastric cancer should be implemented only in selected patients in whom complete resection is possible.

• Smart Structures and Systems
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• v.11 no.3
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• pp.299-314
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• 2013

This paper presents a nonlinear time series analysis technique for evaluating machine defect severity, based on the Recurrence Plot (RP) entropy. The RP entropy is calculated from the probability distribution of the diagonal line length in the recurrence plot, which graphically depicts a system's dynamics and provides a global picture of the autocorrelation in a time series over all available time-scales. Results of experimental studies conducted on a spindle-bearing test bed have demonstrated that, as the working condition of the bearing deteriorates due to the initiation and/or progression of structural damages, the frequency information contained in the vibration signal becomes increasingly complex, leading to the increase of the RP entropy. As a result, RP entropy can serve as an effective indicator for defect severity assessment of rolling bearings.

• Korean Journal of Radiology
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• v.24 no.3
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• pp.235-246
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• 2023

Objective: It is difficult to predict the treatment response of tissue after stereotactic radiosurgery (SRS) because radiation necrosis (RN) and tumor recurrence can coexist. Our study aimed to predict tumor recurrence, including the recurrence site, after SRS of brain metastasis by performing a longitudinal tumor habitat analysis. Materials and Methods: Two consecutive multiparametric MRI examinations were performed for 83 adults (mean age, 59.0 years; range, 27-82 years; 44 male and 39 female) with 103 SRS-treated brain metastases. Tumor habitats based on contrast-enhanced T1- and T2-weighted images (structural habitats) and those based on the apparent diffusion coefficient (ADC) and cerebral blood volume (CBV) images (physiological habitats) were defined using k-means voxel-wise clustering. The reference standard was based on the pathology or Response Assessment in Neuro-Oncologycriteria for brain metastases (RANO-BM). The association between parameters of single-time or longitudinal tumor habitat and the time to recurrence and the site of recurrence were evaluated using the Cox proportional hazards regression analysis and Dice similarity coefficient, respectively. Results: The mean interval between the two MRI examinations was 99 days. The longitudinal analysis showed that an increase in the hypovascular cellular habitat (low ADC and low CBV) was associated with the risk of recurrence (hazard ratio [HR], 2.68; 95% confidence interval [CI], 1.46-4.91; P = 0.001). During the single-time analysis, a solid low-enhancing habitat (low T2 and low contrast-enhanced T1 signal) was associated with the risk of recurrence (HR, 1.54; 95% CI, 1.01-2.35; P = 0.045). A hypovascular cellular habitat was indicative of the future recurrence site (Dice similarity coefficient = 0.423). Conclusion: After SRS of brain metastases, an increased hypovascular cellular habitat observed using a longitudinal MRI analysis was associated with the risk of recurrence (i.e., treatment resistance) and was indicative of recurrence site. A tumor habitat analysis may help guide future treatments for patients with brain metastases.

• Journal of the Korean Data and Information Science Society
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• v.24 no.6
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• pp.1103-1112
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• 2013

Exploratory data analysis focuses mostly on data exploration instead of model fitting. We can use the recurrence plot as a graphical exploratory data analysis tool. With the recurrence plot, we can obtain the structural pattern of the time series and recognize the structural change points in time series at a glance.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.9
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• pp.3973-3976
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• 2015

Objectives: To explore the expression of aquaporin 1 ($AQP_1$) in bladder uroepithelium cell carcinoma (BUCC) and its relevance to recurrence. Materials and Methods: Tissue samples from 45 BUCC patients who underwent total cystectomy or transurethral resection of bladder tumor (TURBT) and from 40 patients with non-bladder cancers who underwent special detection or treatments were collected. The level of expression of $AQP_1$ in BUCC tissues and normal bladder tissues was assessed by immunohistochemistry so as to analyze the relevance to pathological patterns and time of recurrence in BUCC patients. Results: The expression levels of $AQP_1$ normal bladder tissues and BUCC tissues were $2.175{\pm}0.693$ and $3.689{\pm}0.701$, respectively, and the difference was significant (t=9.99, P<0.0001). Marked increase was noted with BUCC histological grade and pathological stage (P<0.01). Moreover, the expression of $AQP_1$ was evidently higher in cancerous tissues with lymph node metastasis than in those without (P<0.01). With short-term recurrence, the positive cell expression rate of $AQP_1$ was higher in primary tissues, which increased obviously after recurrence. Additionally, the recurrent time of BUCC was negatively associated with the positive cell expression rate of $AQP_1$ and the difference between the expression of $AQP_1$ before and after recurrence (r=-0.843, F=39.302, P=0.000; r=-0.829, F=35.191, P=0.000). Conclusions: $AQP_1$, which reflects the grade, stage, lymph node metastasis and recurrence of BUCC, has potential guiding significance in the diagnosis and treatment of bladder cancarcinoma.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.9
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• pp.3861-3866
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• 2015

Background: The aim of this study was to analyze the patterns of relapse and survival outcomes in Northern Thai women with recurrent endometrial cancer (EC). Materials and Methods: Medical records were abstracted from EC patients who underwent primary surgery from 1999 to 2012. Data on clinicopathologic variables, sites of first recurrence, time to relapse of disease, and overall survival (OS) was analyzed. Associations between the clinicopathological variables and the rates of disease recurrence were determined. Results: Among 1,204 reviewed records, 42 eligible patients were identified with recurrent disease. The median age was 55 years and the median follow-up time was 26.0 months. The median times to recurrence (TTR) after completion of the initial treatment in the group of local relapse (LR) and distant/combined sites of recurrence (DCSR) was 6.6 (95% CI=4.6 to 8.6 months) and 16.9 months (95% CI=5.6 to 28.2 months), respectively (p=0.36). The 2-year survival and 3-year survival probability in the group of LR was 54.2% (95% CI=27.2 to 81.3%) and 34.7% (95% CI=9.2 to 60.2%), compared to 50.4% (95% CI=41.1 to 59.7%) and 42.1% (95%CI= 24.1 to 60.1%) for those with DCSR. Distant recurrence was the most frequent pattern of relapse. Overall survival was not significantly different in patients with local relapse when compared to those with DCSR (p=0.69). Conclusions: Patients with recurrence of EC after primary treatment had a worse prognosis and clinical aggressiveness. LR and DCSR occurred most during the first three years. The common sites of relapses were vaginal cuff, pelvis, and lungs. No significant clinicopathological predictor for survival outcomes was identified.

• Journal of Gastric Cancer
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• v.22 no.4
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• pp.369-380
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• 2022

Purpose: Tumor recurrence is the principal cause of poor outcomes in remnant gastric cancer (RGC) after resection. We sought to elucidate the recurrent patterns according to tumor locations in RGC. Materials and Methods: Data were collected from the Shanghai Cancer Center between January 2006 and December 2020. A total of 129 patients with RGC were included in this study, of whom 62 had carcinomas at the anastomotic site (group A) and 67 at the non-anastomotic site (group N). The clinicopathological characteristics, surgical results, recurrent diseases, and survival were investigated according to tumor location. Results: The time interval from the previous gastrectomy to the current diagnosis was 32.0±13.0 and 21.0±13.4 years in groups A and N, respectively. The previous disease was benign in 51/62 cases (82.3%) in group A and 37/67 cases (55.2%) in group N (P=0.002). Thirty-three patients had documented sites of tumor recurrence through imaging or pathological examinations. The median time to recurrence was 11.0 months (range, 1.0-35.1 months). Peritoneal recurrence occurred in 11.3% (7/62) of the patients in group A versus 1.5% (1/67) of the patients in group N (P=0.006). Hepatic recurrence occurred in 3.2% (2/62) of the patients in group A versus 13.4% (9/67) of the patients in group N (P=0.038). Patients in group A had significantly better overall survival than those in group N (P=0.046). Conclusions: The tumor location of RGC is an essential factor for predicting recurrence patterns and overall survival. When selecting an optimal postoperative follow-up program for RGC, physicians should consider recurrent features according to the tumor location.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1998.04a
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• pp.58-65
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• 1998

A purpose of this research is to develope the calculation methods of design input seismic loads, Where, calculation methods are ; (1) Considering different recurrence period of earthquakes which was proposed by ATC 14. (2) Using earthquake records which was modified Korean codes. Responce spectra that was adopted by codes has an estimated recurrence interval of 500 years, with approximately a 90 percent probability of not being exceeded in 50 years. But If we considered the life-time of existing buildings in some cases, response spectra be modified with return period of earthquakes. If we be design highrise and irregular buildings, dynamic analysis method that use time history records should be used. But in Korea, time history records of earthquakes was very few. Therefore to use foreign countries's earthquake record, it is need to select of records considered Korean coeds. As a results, this study propose a calculation method of seismic design input loads that considered return period of earthquakes and also propose using method of earthquakes.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.10
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• pp.4735-4739
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• 2016

Background: Intrahepatic cholangiocarcinoma (IHCCA) is an aggressive tumor for which surgical resection is a mainstay of treatment. However, recurrence after resection is common associated with a poor prognosis. Studies regarding recurrence of mass-forming IHCCA are rare; therefore, we investigated the pattern with our dataset. Methods: We retrospectively reviewed the medical and pathological records of 50 mass-forming IHCCA patients who underwent hepatic resection between January 2004 and December 2009 in order to determine the patterns of recurrence and prognosis. All demographic and operative parameters were analyzed for their effects on recurrence-free survival. Results: The median recurrence-free survival time was 188 days (95%CI: 149-299). The respective 1-, 2-, and 3-year recurrence-free survival rates were 16.2% (95%CI: 6.6-29.4), 5.4% (95%CI: 1.0-15.8) and 2.7% (95%CI: 0.2-12.0). There was an equal distribution of recurrence at solitary and multiple sites. Univariate analysis revealed no factors related to recurrence-free survival.Conclusion: The overall survival and recurrence-free survival after surgery for mass-forming IHCCA were found to be very poor. Almost all recurrences were detected within 2 years after surgery. Adjuvant chemotherapy after surgery may add benefit in the affected patients.