Background/Aims: A poor prognostic factor for Crohn’s disease (CD) includes perianal fistulizing disease, including perianal fistula and/or perianal abscess. Currently, a tool to assess perianal symptoms in patients with CD remains nonexistent. This study aimed to develop a perianal fistulizing disease self-screening questionnaire for patients with CD. Methods: This prospective pilot study was conducted at three tertiary referral centers between January 2019 and May 2020. We formulated questions on perianal symptoms, including tenesmus, anal discharge, bleeding, pain, and heat. A 4-point Likert scale was used to rate each question. Patients with CD completed a questionnaire and underwent pelvic magnetic resonance imaging (MRI). Results: Overall, 93 patients were enrolled, with 51 (54.8%) diagnosed with perianal fistulizing disease, as determined by pelvic MRI. The Spearman correlation findings demonstrated that anal pain (p = 0.450, p < 0.001) and anal discharge (p = 0.556, p < 0.001) were the symptoms that most significantly correlated with perianal disease. For anal pain and discharge, the area under the receiver operating characteristic curve of the scores was significantly higher than that of the combined score for all five symptoms (0.855 vs. 0.794, DeLong’s test p = 0.04). For the two symptoms combined, the sensitivity, specificity, and positive predictive and negative predictive values were 88.2, 73.8, 80.4, and 83.8%, respectively, with 81.7% accuracy for detecting perianal fistulizing disease. Conclusions This study indicates that simple questions regarding anal pain and discharge can help accurately identify the presence of perianal fistulizing disease in patients with CD.

Objectives: We introduced the cohort studies included in the Korean Cohort Consortium (KCC), focusing on large-scale cohort studies established in Korea with a prolonged follow-up period. Moreover, we also provided projections of the follow-up and estimates of the sample size that would be necessary for big-data analyses based on pooling established cohort studies, including population-based genomic studies. Methods: We mainly focused on the characteristics of individual cohort studies from the KCC. We developed “PROFAN”, a Shiny application for projecting the follow-up period to achieve a certain number of cases when pooling established cohort studies. As examples, we projected the follow-up periods for 5000 cases of gastric cancer, 2500 cases of prostate and breast cancer, and 500 cases of non-Hodgkin lymphoma. The sample sizes for sequencing-based analyses based on a 1:1 case-control study were also calculated. Results: The KCC consisted of 8 individual cohort studies, of which 3 were community-based and 5 were health screening-based cohorts. The population-based cohort studies were mainly organized by Korean government agencies and research institutes. The projected follow-up period was at least 10 years to achieve 5000 cases based on a cohort of 0.5 million participants. The mean of the minimum to maximum sample sizes for performing sequencing analyses was 5917-72 102. Conclusions We propose an approach to establish a large-scale consortium based on the standardization and harmonization of existing cohort studies to obtain adequate statistical power with a sufficient sample size to analyze high-risk groups or rare cancer subtypes.

Purpose: Alpha-fetoprotein (AFP) is a prognostic marker for hepatocellular carcinoma (HCC). We investigated the prognostic value of AFP levels in patients who achieved complete response (CR) to transarterial chemoembolization (TACE) for HCC. Materials and Methods: Between 2005 and 2018, 890 patients with HCC who achieved a CR to TACE were recruited. An AFP responder was defined as a patient who showed elevated levels of AFP (>10 ng/mL) during TACE, but showed normalization or a >50% reduction in AFP levels after achieving a CR. Results: Among the recruited patients, 569 (63.9%) with naïve HCC and 321 (36.1%) with recurrent HCC after complete resection were treated. Before TACE, 305 (34.3%) patients had multiple tumors, 219 (24.6%) had a maximal tumor size >3 cm, and 22 (2.5%) had portal vein tumor thrombosis. The median AFP level after achieving a CR was 6.36 ng/mL. After a CR, 473 (53.1%) patients experienced recurrence, and 417 (46.9%) died [median progression-free survival (PFS) and overall survival (OS) of 16.3 and 62.8 months, respectively]. High AFP levels at CR (>20 ng/mL) were independently associated with a shorter PFS [hazard ratio (HR)=1.403] and OS (HR=1.284), together with tumor multiplicity at TACE (HR=1.518 and 1.666, respectively). AFP non-responders at CR (76.2%, n=359 of 471) showed a shorter PFS (median 10.5 months vs. 15.5 months, HR=1.375) and OS (median 41.4 months vs. 61.8 months, HR=1.424) than AFP responders (all p=0.001). Conclusion High AFP levels and AFP non-responders were independently associated with poor outcomes after TACE. AFP holds clinical implications for detailed risk stratification upon achieving a CR after TACE.

Purpose: Breast cancer is the second most common malignancy in Korean women, and its incidence has increased rapidly. The purpose of this study was to evaluate the treatment outcomes of patients with breast cancer treated at a low volume center. Methods: We retrospectively analyzed 401 patients with stage I-III breast cancer at Chosun University Hospital from January 1998 to December 2013. We reviewed medical records including clinical information and pathologic reports. Results: We found 401 cases of newly diagnosed breast cancer, including 5 (1.2%) male breast cancer patients. According to histological features, there were 43 cases (ductal carcinoma in situ (DCIS): 35 cases [8.7%], lobular carcinoma in situ (LCIS): 8 cases [2.0%]) of non-invasive carcinoma, 350 cases (87.3%) of invasive carcinoma, 2 cases (0.5%) of Paget’s disease, 1 case (0.2%) of malignant phyllodes tumor, 3 cases (0.7%) of sarcoma, and 2 cases (0.5%) of other types. With respect to disease stage, 117 (29.2%) patients were in stage I, 176 (43.9%) in stage II, and 78 (19.4%) in stage III. The type of surgical approaches were breast-conserving surgery (153, 38.2%), modified radical mastectomy (243, 60.6%), wide excision (4, 1.0%), and others (1, 0.2%). Five-year disease-free survival rates were 100% (stage 0), 95.4% (stage I), 91.4% (stage IIa), 75% (stage IIb), 78% (stage IIIa), 50% (stage IIIb), and 59.2% (stage IIIc). Overall survival rates were 100% (stage 0), 96.2% (stage I), 94.3% (stage IIa), 85.4% (stage IIb), 84.8% (stage IIIa), 50% (stage IIIb), and 55.5% (stage IIIc). Conclusion Although the patients were treated at a low-volume center, their favorable survival outcomes are notable. Further multicenter (low-volume centers) research is warranted.

PURPOSE: The purpose of this study was to investigate the radiologic and serologic factors related to postoperative union using intramedullary (IM) internal fixation in atypical femoral fractures (AFF), which are closely related to bisphosphonates (BPs) for osteoporosis. MATERIALS AND METHODS: From February 2008 to December 2016, 65 patients (71 cases) who had undergone IM nail fixation after diagnosis of AFF were enrolled in this study. Patients were divided into group A, who experienced union within 6 months and group B, who did not experience union within 6 months. They were evaluated for duration of BPs use, radiologic factors and serological factors. RESULTS: The mean duration of BPs use was 6.17 years in group A and 8.24 years in group B (p=0.039). In the subtrochanteric area, there were 14 cases (27.5%) in group A and 14 cases (70.0%) in group B. In the femoral shaft, there were 37 cases (72.5%) in group A and 6 cases (30.0%) in group B (p=0.001). On the preoperative, the flexion in the coronal plane was 5.9° (2.1°–9.2°) in group A and 8.0° (3.1°–12.1°) in group B (p=0.041). On the postoperative, conversion to valgus was 15 cases (29.4%), 8 cases (40.0%); conversion to neutral was 34 cases (66.7%) and 8 cases (40.0%); conversion to varus was 2 cases (3.9%) and 4 cases (20.0%), each (p=0.037). The fracture site gap was 1.5 mm (0–2.9 mm) on the front side and 1.2 mm (0–2.2 mm) on lateral side and 2.2 mm (0.9–4.7 mm) and 1.9 mm (0.5–3.5 mm), each (p=0.042, p=0.049). Among serological factors, there was no significant difference between the two groups. CONCLUSION: Factors adversely affecting the union should be recognized before surgery, such as longterm BPs use or a severe degree of bending of the femur in the coronal plane. During surgery, proper reduction and spacing of the fracture site on the coronal plane should allow adequate reduction of the anterior and posterior surfaces. Obtaining anatomic reduction would be most beneficial for union, but if that is not possible, obtaining congenital valgus rather than varus on the coronal plane may be helpful for union.
Diagnosis ; Diphosphonates ; Femoral Fractures ; Femur ; Humans ; Osteoporosis

BACKGROUND: Understanding the burden of disease is important to establish cost-effective treatment strategies and to allocate healthcare resources appropriately. However, little reliable information is available regarding the overall economic burden imposed by chronic obstructive pulmonary disease (COPD) in Korea. METHODS: This study is a multicenter observational research on the COPD burden in Korea. Total COPD costs were comprised of three categories: direct medical, direct non-medical, and indirect costs. For direct medical costs, institutional investigation was performed at 13 medical facilities mainly based on the claims data. For direct non-medical and indirect costs, site-based surveys were administered to the COPD patients during routine visits. Total costs were estimated using the COPD population defined in the recent report. RESULTS: The estimated total costs were approximately 1,245 million US dollar (1,408 billion Korean won). Direct medical costs comprised approximately 20% of the total estimated costs. Of these, formal medical costs held more than 80%. As direct non-medical costs, nursing costs made up the largest percentage (39%) of the total estimated costs. Costs for COPD-related loss of productivity formed four fifths of indirect costs, and accounted for up to 33% of the total costs. CONCLUSION: This study shows for the first time the direct and indirect costs of COPD in Korea. The total costs were enormous, and the costs of nursing and lost productivity comprised approximately 70% of total costs. The results provide insight for an effective allocation of healthcare resources and to inform establishment of strategies to reduce national burden of COPD.
Delivery of Health Care ; Efficiency ; Health Care Costs ; Humans ; Korea* ; Nursing ; Pulmonary Disease, Chronic Obstructive*

Amputation of the lower extremities followed by the use of an artificial leg is very common. However, malignancy arising in an amputation stump is an extremely rare event. In this report, we describe a case of squamous cell carcinoma arising in the amputation stump of a 56-year-old Korean man. To the best of our knowledge, similar cases have not been previously reported in Korea.
Amputation Stumps ; Amputation ; Artificial Limbs ; Carcinoma, Squamous Cell ; Epithelial Cells ; Humans ; Korea ; Lower Extremity ; Middle Aged

BACKGROUND: Procollagen type I N-terminal propeptide (PINP) is one of the most clinically useful bone formation biomarkers. Therefore, the purpose of this study was to independently evaluate the performance of automated total PINP assay and established age- and gender-specific reference intervals for PINP in healthy Korean population. METHODS: The imprecision, linearity, and detection capability of Elecsys total PINP assay was determined and reference interval was established using 599 serums from Korean population with normal bone mineral densities based on bone densitometry. Age groups were divided into 20s, 30s, 40s, 50s, 60s and over. RESULTS: Elecsys total PINP had excellent performance in imprecision, linearity, and detection capability. When partitioning age groups in Korean male and female populations, there was significant difference in total PINP between different age groups. In male populations, PINP level was decreased with increasing age, then it remained steady after middle-age. In female populations, there was a decreasing tendency similar to that in the male population with a sharp increase in the 50 to 59 age group. CONCLUSIONS: Elecsys total PINP assay showed precise and reliable performance in our study. We established age-related PINP reference intervals for Korean male and female population with normal bone mineral densities.
Biomarkers ; Bone Density ; Collagen Type I ; Densitometry ; Female ; Humans ; Male ; Osteogenesis ; Peptide Fragments ; Procollagen ; Reference Values

OBJECTIVES: The objective of this study was to investigate the effect of pharmacological treatments for attention-deficit hyperactivity disorder (ADHD) on motor coordination, using the Developmental Coordination Disorder Questionnaire (DCDQ). METHODS: The participants were recruited from April 2015 to November 2016 from the Department of Psychiatry of Asan Medical Center and were treated for 3 months with methylphenidate or atomoxetine. The illness severity at baseline and 3 months were scored using the ADHD Rating Scale (ARS), Clinical Global Impression-Severity Scale (CGI-S) and/or Clinical Global Impression-Improvement Scale (CGI-I). A total of 39 children with ADHD (age 8.0±1.4 years, 36 boys) completed the Advanced Test of Attention (ATA) and their parents completed the DCDQ at baseline and 3 months. The paired t-test, mixed between-within analysis of variance and correlation analysis were used. RESULTS: The CGI-S (p<0.001), ARS (p<0.001), and fine motor/hand writing (p=0.005) on the DCDQ were significantly changed between pre-treatment and post-treatment. When the participants were divided into those who were suspected of having developmental coordination disorder (DCD) (n=23) and those who probably did not (n=16), the control during movement, fine motor/hand writing and general coordination scores on the DCDQ showed the main effects for group (p<0.001, p<0.001 and p<0.001, respectively). The fine motor/hand writing on the DCDQ has a significant main effect for time [F(1,37)=7.31, p=0.010, η2=0.405] and the interaction effect between group and time was also significant [F(1,37)=4.63, p=0.038, η2=0.111]. The baseline visual commission error on the ATA is significantly correlated with the changes in the DCDQ total scores (r=0.330, p=0.040). CONCLUSION: Our results provide preliminary evidence that pharmacological treatment for ADHD improves not only the core symptoms of ADHD, but also the motor coordination. Further studies are needed to confirm the effect of the pharmacological treatment for ADHD on the motor coordination.
Atomoxetine Hydrochloride ; Child ; Chungcheongnam-do ; Drug Therapy ; Humans ; Methylphenidate ; Motor Skills Disorders ; Parents ; Writing

PURPOSE: To compare the new swept-source optical coherence tomography based IOL Master 700 to both the partial coherence interferometry based IOL Master 500 and ultrasound A-scan in terms of the ocular biometry and the prediction of postoperative refractive outcomes. METHODS: A total 67 eyes of 55 patients who received cataract surgery were included in our study. The axial length, anterior chamber depth, and keratometry were measured using IOL Master 700, IOL Master 500, and A-scan. The predictive errors, which are the differences between predictive refraction and post-operative refraction 1 month after surgery, were also compared. RESULTS: Axial length measurements were not successful in 5 eyes measured using IOL Master 700 and in 12 eyes measured using IOL Master 500. The mean absolute postoperative refraction predictive errors were 0.63 ± 0.50 diopters, 0.66 ± 0.51 diopters, and 0.62 ± 0.51 diopters for IOL Master 700, IOL Master 500, and A-scan, respectively, and these values exhibited no statistically significant differences. The mean axial lengths were 24.25 ± 2.41 mm, 24.24 ± 2.40 mm, and 24.22 ± 2.39 mm; the mean anterior chamber depths were 3.09 ± 0.39 mm, 3.17 ± 0.39 mm, and 3.15 ± 0.46 mm; and the mean keratometry values were 44.12 ± 1.82 diopters, 44.57 ± 2.10 diopters, and 43.98 ± 1.84 diopters for the IOL Master 700, IOL Master 500, and A-scan groups, respectively. None of these parameters showed statistically significant differences between the three groups. Regarding pair-wise comparison, there were significant differences between the IOL Master 700 and the other devices. CONCLUSIONS: The ocular biometric measurements measured using IOL Master 700, IOL Master 500, and A-scan showed no significant differences. However, IOL Master 700 demonstrated a superior ability to successfully take biometric measurements compared to IOL Master 500. Therefore, IOL Master 700 is capable of measuring ocular biometry for cataract surgery in clinical practice.
Anterior Chamber ; Biometry* ; Cataract ; Humans ; Interferometry ; Lenses, Intraocular ; Tomography, Optical Coherence ; Ultrasonography*