We aimed to identify blood lymphocytes as a prognostic factor for survival in patients with locally advanced stage III non-small cell lung cancer (NSCLC) treated with concurrent chemoradiotherapy (CCRT). This is a secondary study of 196 patients enrolled in the Korean Radiation Oncology Group 0903 phase III clinical trial to evaluate the prognostic significance of circulating blood lymphocyte levels. The median total lymphocyte count (TLC) reduction ratio during CCRT was 0.74 (range: 0.29-0.97). In multivariate analysis, patient age (p=0.014) and gross tumor volume (GTV, p=0.031) were significant factors associated with overall survival, while TLC reduction (p=0.018) and pretreatment neutrophil-to-lymphocyte ratio (NLR; p=0.010) were associated with progression-free survival (PFS). In multivariate logistic regression analysis, pretreatment NLR, GTV, and heart V20 were significantly associated with TLC reduction. Immunohistochemical analysis of programmed death ligand 1 and CD8 expression on T cells was performed on 84 patients. CD8 expression was not significantly associated with the pretreatment lymphocyte count (p=0.673), and PDL1 expression was not significantly associated with OS or PFS. Univariate analysis revealed that high CD8 expression in TILs was associated with favorable OS and was significantly associated with favorable PFS (p=0.032). TLC reduction during CCRT is a significant prognostic factor for PFS, and heart V20 is significantly associated with TLC reduction. Thus, in the era of immunotherapy, constraining the volume of the radiation dose to the whole heart must be prioritized for the better survival outcomes.

Background: Obstructive sleep apnea (OSA) is closely related to maternal obesity in pregnant women, and the association increases with later pregnancy. Obesity and OSA are risk factors of pregnancy-related complications, including gestational hypertension, gestational diabetes mellitus (GDM), and fetal morbidities. We aimed to determine the prevalence of OSA and to assess the impact of OSA on pregnancy-related disorders in overweight pregnant women. Methods: Eligible participants who were overweight [body mass index (BMI) ≥ 23 kg/m 2 ] in gestational age 30 weeks or more, assessed OSA using a portable polysomnography at home.Clinical data were collected from pregnant women and their babies. Results: The average age of 51 participants was 34.5 years (27–44 years). The number of primipara was 25 (49%) and that of multipara was 26 (51%). Eight cases of GDM (15.7%) and five cases of preeclampsia (9.8%) were reported, and six patients (11.8%) experienced preterm delivery. In results of polysomnography, 14 patients (27.5%) were diagnosed as OSA. Apnea-hypopnea index moderately correlated with BMI (r = 0.515, P < 0.001). The BMI (P < 0.005) and preeclampsia rate (P < 0.017) were higher in the OSA group compared to the control group. Odds ratios (ORs) adjusting age, BMI, parity, and abortion history were calculated. The presence of OSA increased OR of preeclampsia (OR, 13.1; 95% confidence interval, 1.1–171.3). The majority of preeclampsia patients (4/5, 80%) underwent preterm delivery. Conclusion OSA is an important risk factor for preeclampsia, resulting in preterm delivery.For overweight pregnant women, an OSA evaluation should be mandatory.

The introduction of device-assisted enteroscopy (DAE) in the beginning of the 21st century has revolutionized the diagnosis and treatment of diseases of the small intestine. In contrast to capsule endoscopy, the other main diagnostic modality of small bowel diseases, DAE has the unique advantages of allowing the observation of the region of interest in detail and enabling tissue acquisition and therapeutic intervention. As DAE becomes an essential procedure in daily clinical practice, there is an increasing need for correct guidelines on when and how it is to be performed and what technical factors should be taken into consideration. In response to these needs, the Korean Association for the Study of Intestinal Diseases has developed an expert consensus statement on the performance of DAE by reviewing current evidence. This expert consensus statement particularly focuses on the indications, choice of insertion route, therapeutic intervention, complications, and relevant technical points.

Primary mucosa-associated with a lymphoid tissue (MALT) lymphoma is a rare distinct subtype of non-Hodgkin’s lymphoma that occurs in approximately 8% of all non-Hodgkin lymphomas. Primary gastrointestinal MALT lymphoma usually occurs in the stomach, but duodenal involvement is extremely rare. Therefore, the clinical manifestations, treatment, and prognosis of primary duodenal MALT lymphoma have not yet been validated because of its rarity. This paper reports a case of a 40-year-old male with primary duodenal MALT lymphoma who was treated successfully with radiation therapy alone. A 40-year-old male visited for a medical check-up.Esophagogastroduodenoscopy revealed whitish multi-nodular mucosal lesions in the second and third portions of the duodenum. Biopsy specimens from mucosal lesions in the duodenum were reported to be suspicious for MALT lymphoma of the duodenum. He received a total dose of 3,000 cGy in 15 fractions with external beam radiation therapy for three weeks. Three months after radiation therapy, an endoscopic examination revealed complete resolution of the duodenal lesions. The follow-up 12 months after radiation therapy showed no evidence of tumor recurrence.

Tuberculosis is an adverse event in patients with Crohn’s disease receiving anti-tumor necrosis factor (TNF) therapy. However, tuberculosis presenting as a bronchoesophageal fistula (BEF) is rare. We report a case of tuberculosis and BEF in a patient with Crohn’s disease who received anti-TNF therapy. A 33-year-old Korean woman developed fever and cough 2 months after initiation of anti-TNF therapy. And the symptoms persisted for 1 months, so she visited the emergency room. Chest computed tomography was performed upon visiting the emergency room, which showed BEF with aspiration pneumonia. Esophagogastroduodenoscopy with biopsy and endobronchial ultrasound with transbronchial needle aspiration confirmed that the cause of BEF was tuberculosis. Anti-tuberculosis medications were administered, and esophageal stent insertion through endoscopy was performed to manage the BEF. However, the patient’s condition did not improve; therefore, fistulectomy with primary closure was performed. After fistulectomy, the anastomosis site healing was delayed due to severe inflammation, a second esophageal stent and gastrostomy tube were inserted. Nine months after the diagnosis, the fistula disappeared without recurrence, and the esophageal stent and gastrostomy tube were removed.

The introduction of device-assisted enteroscopy (DAE) in the beginning of 21st century has revolutionized the diagnosis and treatment of diseases of the small intestine. In contrast to capsule endoscopy, the other main diagnostic modality of the small bowel diseases, DAE has the unique advantages of observing the region of interest in detail and enabling tissue acquisition and therapeutic intervention. As DAE becomes an essential procedure in daily clinical practice, there is an increasing need for correct guidelines on when and how to perform it and what technical factors should be considered. In response to these needs, the Korean Association for the Study of Intestinal Diseases developed an expert consensus statement on the performance of DAE by reviewing the current evidence. This expert consensus statement particularly focuses on the indications, choice of insertion route, therapeutic intervention, complications, and relevant technical points.

Background/Aims: We investigated the real-world effectiveness and safety of ustekinumab (UST) as induction treatment for Koreans with Crohn’s disease (CD). Methods: CD patients who started UST were prospectively enrolled from 4 hospitals in Korea. All enrolled patients received intravenous UST infusion at week 0 and subcutaneous UST injection at week 8. Clinical outcomes were assessed using Crohn’s Disease Activity Index (CDAI) scores at weeks 8 and 20 among patients with active disease (CDAI ≥150) at baseline. Clinical remission was defined as a CDAI <150, and clinical response was defined as a reduction in CDAI ≥70 points from baseline. Safety and factors associated with clinical remission at week 20 were also analyzed. Results: Sixty-five patients were enrolled between January 2019 and December 2020. Among 49 patients with active disease at baseline (CDAI ≥150), clinical remission and clinical response at week 8 were achieved in 26 (53.1%) and 30 (61.2%) patients, respectively. At week 20, 27 (55.1%) and 35 (71.4%) patients achieved clinical remission and clinical response, respectively. Twenty-seven patients (41.5%) experienced adverse events, with serious adverse events in 3 patients (4.6%). One patient (1.5%) stopped UST therapy due to poor response. Underweight (body mass index <18.5 kg/m2) (odds ratio [OR], 0.085; 95% confidence interval [CI], 0.014–0.498; P=0.006) and elevated C-reactive protein at baseline (OR, 0.133; 95% CI, 0.022–0.823; P=0.030) were inversely associated with clinical remission at week 20. Conclusions UST was effective and well-tolerated as induction therapy for Korean patients with CD.

Background/Aims: Although pediatric ulcerative colitis (UC) has a different phenotype and clinical course than adult UC, its clinical features and outcomes are poorly defined, especially in Asian populations. This study investigated the clinical features and long-term outcomes of pediatric UC in a Korean population. Methods: We retrospectively analyzed 208 patients aged <18 years diagnosed with UC between 1987 and 2013. The patient characteristics at diagnosis according to the Paris classification and the clinical course were analyzed. Results: The male-to-female ratio was 1.3:1, and the median patient age was 15.5 years. At diagnosis, 28.8% of patients had proctitis (E1), 27.8%, left-sided colitis (E2); 5.2%, extensive colitis (E3); and 38.2%, pancolitis (E4). The cumulative probabilities of extension after 5, 10, 15, and 20 years were 32.7%, 40.4%, 52.5%, and 65.8%, respectively. Eighteen patients underwent colectomy, and three patients had colorectal cancer. The cumulative probabilities of colectomy after 5, 10, 15, and 20 years were 7.1%, 8.9%, 12.6%, and 15.6%, and those of colorectal cancer after 10, 15, and 20 years were 0%, 2.1%, and 12.0%, respectively. The disease extent, Pediatric Ulcerative Colitis Activity Index severity, and systemic corticosteroid therapy were significant risk factors for colectomy. The development of primary sclerosing cholangitis was significantly associated with colorectal cancer. Conclusions This study provides detailed information on the disease phenotype and long-term clinical outcomes in a large cohort of Korean children with UC. They have extensive disease at diagnosis, a high rate of disease extension, and a low rate of cumulative colectomy.

Background/Aims: Little is known about the clinical course of hepatitis B virus (HBV)-infected patients undergoing anti-tumor necrosis factor α (TNF-α) therapy for inflammatory bowel disease (IBD). We aimed to investigate the clinical course of HBV infection and IBD and to analyze liver dysfunction risks in patients undergoing anti-TNF-α therapy. Methods: This retrospective multinational study involved multiple centers in Korea, China, Tai-wan, and Japan. We enrolled IBD patients with chronic or resolved HBV infection, who received anti-TNF-α therapy. The patients’ medical records were reviewed, and data were collected using a web-based case report form. Results: Overall, 191 patients (77 ulcerative colitis and 114 Crohn’s disease) were included, 28.3% of whom received prophylactic antivirals. During a median follow-up duration of 32.4 months, 7.3% of patients experienced liver dysfunction due to HBV reactivation. Among patients with chronic HBV infection, the proportion experiencing liver dysfunction was significantly higher in the non-prophylaxis group (26% vs 8%, p=0.02). Liver dysfunction occurred in one patient with resolved HBV infection. Antiviral prophylaxis was independently associated with an 84% reduction in liver dysfunction risk in patients with chronic HBV infection (odds ratio, 0.16; 95% confidence interval, 0.04 to 0.66; p=0.01). The clinical course of IBD was not associated with liver dysfunction or the administration of antiviral prophylaxis. Conclusions Liver dysfunction due to HBV reactivation can occur in HBV-infected IBD patients treated with anti-TNF-α agents. Careful monitoring is needed in these patients, and antivirals should be administered, especially to those with chronic HBV infection.