• Journal of the Korean Society of Radiology
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• v.81 no.5
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• pp.1164-1174
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• 2020

Purpose To evaluate a deep learning model to predict recurrence of thyroid tumor using preoperative ultrasonography (US). Materials and Methods We included representative images from 229 US-based patients (male:female = 42:187; mean age, 49.6 years) who had been diagnosed with thyroid cancer on preoperative US and subsequently underwent thyroid surgery. After selecting each representative transverse or longitudinal US image, we created a data set from the resulting database of 898 images after augmentation. The Python 2.7.6 and Keras 2.1.5 framework for neural networks were used for deep learning with a convolutional neural network. We compared the clinical and histological features between patients with and without recurrence. The predictive performance of the deep learning model between groups was evaluated using receiver operating characteristic (ROC) analysis, and the area under the ROC curve served as a summary of the prognostic performance of the deep learning model to predict recurrent thyroid cancer. Results Tumor recurrence was noted in 49 (21.4%) among the 229 patients. Tumor size and multifocality varied significantly between the groups with and without recurrence (p < 0.05). The overall mean area under the curve (AUC) value of the deep learning model for prediction of recurrent thyroid cancer was 0.9 ± 0.06. The mean AUC value was 0.87 ± 0.03 in macrocarcinoma and 0.79 ± 0.16 in microcarcinoma. Conclusion A deep learning model for analysis of US images of thyroid cancer showed the possibility of predicting recurrence of thyroid cancer.

• Journal of the Korean Data and Information Science Society
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• v.25 no.2
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• pp.327-336
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• 2014

Recurrent event data occurs when a subject experiences same type of event repeatedly and is found in various areas such as the social sciences, Economics, medicine and public health. To analyze recurrent event data either a total time or a gap time is adopted according to research interest. In this paper, we analyze recurrent event data with incomplete observation gap using a gap time scale. That is, some subjects leave temporarily from a study and return after a while. But it is not available when the observation gaps terminate. We adopt an interval censoring mechanism for estimating the termination time. Furthermore, to model the association among gap times of a subject, a frailty effect is incorporated into a model. Programs included in Survival package of R program are implemented to estimate the covariate effect as well as the variance of frailty effect. YTOP (Young Traffic Offenders Program) data is analyzed with both proportional hazard model and a weibull regression model.

• Journal of the Korean Society of Radiology
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• v.82 no.3
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• pp.715-720
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• 2021

Transurethral resection (TUR) is the gold standard treatment of non-muscle invasive bladder cancers. Recurrence occurs in approximately half of the patients with bladder cancer after initial TUR. Most recurrent bladder cancers present as polypoid masses with intraluminal growth originating from the mucosa. To the best of our knowledge, there has been no report on imaging findings of recurrent bladder cancers located within the subepithelial and intramural layers. Recurrent cancers within the intramural layer are difficult to detect with cystoscopy; they are also difficult to remove surgically. Imaging studies reveal the most important indicators for diagnosing subepithelial recurrent cancers. Here, we present a rare case of a recurrent bladder cancer within the subepithelial layer detected on imaging.

• Korean Journal of Biological Psychiatry
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• v.14 no.4
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• pp.249-255
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• 2007

Objectives : The aim of this prospective study is to investigate predictors estimating relapse in Korean alcohol-dependent patients using variables like alcohol history, drinking craving, treatment motivation and insight. Methods : Alcohol dependent patients(N=48) who completed questionnaires about sociodemographic variables and drinking history, Timeline Follow-Back(TLFB), Obsessive-Compulsive Drinking Scale(OCSD), Alcohol Urge Questionnaire(AUQ), Pennsylvania Alcohol Craving Scale(PACS), University of Rhode Island Change Assessment(URICA), Hanil Alcohol Insight Scale(HAIS) were followed-up for 24weeks. Subjects who drank heavily(5 standard drinking or more/day) or were not followed up anymore were classified as the relapse group. We used logistic regression analysis with backward elimination of SPSS PC+11.5 to investigate relapse estimate predictors. Results : Average drinking amount per drinking day for last 1 year and HAIS score were predictors of relapse in alcohol-dependent patients. Conclusions : Our findings suggest that therapist should give more attention to alcohol-dependent patients who had more drinks per drinking day for last 1 year and had lower insight level.

• Journal of Oral Medicine and Pain
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• v.33 no.2
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• pp.219-228
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• 2008

The purpose of this study is to compare the differences between first visits and the recurred time of TMD patients about the number of visits, the treatment plans, the symptoms and the results after the conservative treatments. This could lead us to assess the prognoses of TMDs treated conservatively. We investigated 54 patients who have visited the Department of Oral Medicine in PNUH from 1991 to 2001, diagnosed as TMDs and treated conservatively with medications, physical therapies and splints. The treatments were terminated since the subjects have shown much improvements and resumed when TMDs recurred from 1992 to 2002. We researched the diagnoses, symptoms, the number of visits, the treatment plans and the results comparing the time before and after the treatments were carried out and following are the results. 1. Both the primary and the recurred groups improved after having been treated conservatively. 2. Both the primary and the recurred groups showed no differences in pains and MCOs when they first visited though the noises and LOMs turned out to be more serious in primary group. 3. Both the primary and the recurred groups had no differences in pains, noises, LOMs, MCOs when the treatments were over. 4. The results of treatments were not affected by treatment plans, sex, diagnoses in both primary and recurred groups. 5. Most of the patents tended to visit less than 10 times in recurred patients.

• Tuberculosis and Respiratory Diseases
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• v.61 no.6
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• pp.526-532
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• 2006

Backgroud: Traditionally, tuberculous pleurisy has been known to largely develop as primary tuberculosis. However, as the incidence of tuberculosis decrease, recent studies have shown reactivation tuberculosis has become the main cause of tuberculous pleurisy. Methods: 141 cases of tuberculous pleurisy, between January 2003 and February 2006, at the Dankook university hospital. were retrospectively studied. The patients were divided into primary and reactivation tuberculosis. based on the history and radiological characteristics, and the clinical, radiological characteristics at the time of diagnosis and residual pleural thickening after 6 month of chemotherapy were compared between the two groups. Results: 1. Of the 141 tuberculous pleurisy cases, in 135 it was possible to differentiate between primary and reactivation tuberculosis. 2. Of the 135 tuberculous pleurisy cases, 38 (28%) showed a primary tuberculosis pattern, and 98 (72%) showed a reactivation tuberculosis pattern. 3. There were no significant differences between primary and reactivation tuberculosis in relation to age, sex, duration of symptom, amount of pleural effusion, pleural fluid WBC, lymphocyte count, and level of protein, LDH and ADA at the time of diagnosis 4. 124 patients were followed for 6 months after diagnosis of tuberculous pleurisy, and there was no significant difference in the residual pleural thickening between primary and reactivation tuberculosis. Conclusion: In South Korea, a reactivation disease is currently a more common cause of tuberculous pleurisy than a primary disease. There was no difference in the clinical characteristics between primary and reactivation tuberculosis.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.11
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• pp.5094-5101
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• 2011

In order to investigate recurrence rate and risk factors for recurrence of gastric cancer after curative resection, we examined blood biochemical profile and clinicopathological features of 386 gastric cancer patients by using medical charts and data of hospital cancer registry from September 2010 to May 2011. Chi-square test and logistic regression analyses were performed to identify risk factors. The recurrence rate of all gastric cancer patients was 2.6%; The recurrence rate by gender was 3.45% in male and 0.89% in female, and that was 4 times higher in male than in female. On univariate logistic regression analyses, lymph node metastases(OR=8.793), Helicobactor pylori infecton(OR=6.495), abnormal total cholesterol(OR=14.333) were related to recurrence. On multivariate logistic regression analyses, lymph node metastases and H. pylori infection were very important risk factors for recurrence of gastric cancer. In conclusion, lymph node metastases, H. pylori infection, and total cholesterol control were very important to prevent recurrence of gastric cancer, and it needs to monitor blood biochemical (C-reactive protein, carcinoembryonic antigen, etc) for the early detection of gastric cancer recurrence.

• Journal of Chest Surgery
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• v.33 no.11
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• pp.876-880
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• 2000

배경: Maze수술은 승모판 질환에 동반되는 심방세동의 효과적인 치료방법으로 알려져있다. 이 연구는 승모판 수술과 심방세동 수술을 동시에 시행한 환자에서 심방세동 수술 후 중기적인 결과와 그 재발 여부를 조사하였다. 대상 및 방법: 심방세동 수술과 승모판 수술을 받은 11예의 환자(10예는 류마티스성 승모판 질환)를 대상으로 하였다. Maze II 수술 및 그 변형수술을 6예에서 시행했고, Maze III 수술 및 그 변형수술을 5예에서 시행하였다. 심방세동 수술 후 좌심방의 수축정도를 심방세동 수술 없이 승모판 수술만으로 동율동을 얻은 경우와 비교하였다. 결과: Maze II 수술을 받은 환자 6예 중 5예(83.3%)에서, maze III 수술을 받은 환자 5예 모두에서 동율동을 회복하였다(전체적으로 90.9%). 전자의 1예(20%)와 후자의 2예(40%)에서 수술 후 각각 23, 2, 13개월만에 심방세동이 재발하였다. 그 후 다시 2예는 동율동으로 전환되었으나, 1예는 재발된 심방세동을 그대로 유지하고 있다. 변형술을 받은 3예에서는 심방세동의 재발이 없었다. Maze 수술 후 4예(40%)에서만 좌심방의 수축기능을 보였으며, maze 수술 후 좌심방 수축 정도(승모판의 A파의 속도)도 maze 수술 없이 승모판 수술과 항부정맥제 투여로 동율동을 회복한 경우보다 낮았다. 결론: 심방세동을 동반한 승모판 수술 환자에서 maze 수술로써 심방세동으로부터 동율동을 회복할 수 있으나 중기적으로 재발할 수 있으며, maze 수술 후 좌심방 수축정도는 상당히 떨어질 수 있다고 생각된다.

• Radiation Oncology Journal
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• v.17 no.1
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• pp.36-41
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• 1999

Purpose : We reviewed the treatment results for the patients with locally recurrent rectal carcinoma. The object was to evaluate the treatment outcome and to identify the prognostic factors influencing the survival. Methods and Materials: Twenty-eight patients with locally recurrent rectal carcinoma treated principally with external-beam radiation therapy between 1982 to 1996 in the Department of Radiation Oncology at Paik and Hanyang Hospital were reviewed retrospectively Of these, 17 patients had initially abdominoperineal resection, 9 had low anterior resection, and 2 had local excision. No patients had received adjuvant radiation therapy for the primary disease. There were 14 men and 14 women whose ages ranged from 31 to 72 years (median age:54.5). Median time from initial surgery to the start of radiation therapy for local recurrence was 11 months (4~47 months). Radiation therapy was given with total doses ranging from 27 to 64.8 Gy (median=51.2 Gy). Results : The median survival was 16.7 months. The 2-year and 5-year survival rates were 20.1%, 4.1% respectively. Upon multivariate analysis, overall survival was positively correlated with duration of intervals from initial surgery to local recurrence (P=0.039). Relief of pelvic symptoms was achieved in 17 of 28 patients (60.7%). Pain and bleeding responded in 40% and 100% of patients, respectively Conclusions : Patients with locally recurrent rectal carcinoma treated with radiotherapy have benefited symptomatically, and might have increased survivals with a small chance of cure. But, patient were rarely cured (median survival : 10 months, 5-year survival : less than 5%). Overall survival was positively correlated with long intervals from initial surgery to local recurrence. Future efforts should be directed to the use of effective therapy for patients with locally recurrent rectal carcinoma and adjuvant therapy for patients with rectal cancer to reduce the incidence of pelvic recurrence.

• Journal of Gastric Cancer
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• v.5 no.4 s.20
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• pp.222-227
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• 2005

Purpose: There are several reports suggested the usefulness of serum tumor markers, AFP, CEA and CA19-9 as prognostic factors or indicators for recurrence in gastric cancer. This clinical study was peformed to evaluate positive rate of tumor markers according to site of recurrence in gastric cancer. Materials and Methods: From the database of patients who underwent radical gastrectomy for gastric cancer between January 1999 and January 2004, 52 patients who showed recurrence were included in this retrospective study. Serum levels of tumor markers were measured at the time of preoperative diagnosis of the gastric cancer and at the time of postoperative recurrence during follow up, respectively. Results: The overall positivity of tumor markers at the time of recurrence was found to be significantly higher than that of prior to surgery in the recurred group for the single test as well as the combination tests. For the peritoneum, the most common recurrent site, the positivity of CA19-9 was higher at the time of recurrence. And the significant positivity of CEA at the time of recurrence was detected in the liver cases. Conclusion: Having a preoperative positive tumor marker may identify the patient as having an increased chance of a recurrence. Although tumor markers continue to have limited diagnostic significance in gastric cancer, CA19-9 may be useful as a predictor for peritoneal recurrence of the gastric cancer, and CEA for recurrence to liver.