In patients with differentiated thyroid cancer (DTC), initial recurrence risk stratification based on clinical, histopathological, and perioperative data remains the key determinant for guiding management strategies during the first 1-2 years post-treatment. However, the adoption of ongoing risk stratification (ORS), which dynamically reassesses risk by integrating longitudinal clinical data and treatment response, enables more precise long-term prognostic assessment and facilitates highly individualized management. Building upon recent guidelines, the 2026 KTA guideline has been further refined by incorporating robust evidence from large-scale national cohorts and comprehensive systematic reviews. These updated recommendations outline contemporary concepts of ORS, risk-adapted TSH suppression targets, optimized surveillance modalities for recurrence detection, and disease-specific long-term follow-up strategies. Reflecting the paradigm shift toward de-escalated treatment, this revision integrates evolved perspectives on TSH suppression intensity, the clinical interpretation of thyroglobulin levels, and tailored follow-up intervals. These evidence-based recommendations aim to minimize unnecessary treatment and excessive surveillance in the large proportion of patients with excellent prognosis after initial therapy, while ensuring that each patient receives appropriately tailored and effective long-term management.

Purpose: Current guidelines recommend vaccination at least 2 weeks before chemotherapy initiation to optimize the immune response despite limited evidence. Our previous study indicated no differences in short-term immune response for the 13-valent pneumococcal conjugate vaccine (PCV13) according to the vaccination timing. This study aims to investigate the long-term efficacy of PCV13 and clinical factors associated with the respective antibody response. Materials and Methods: Patients with gastric or colorectal cancer who received adjuvant chemotherapy were enrolled and divided into two groups: vaccinated 2 weeks before chemotherapy (arm A) and vaccinated concurrently with chemotherapy (arm B). Serum samples were collected before vaccination and in one month, 3 years, and 5 years. Immune responses were measured using enzyme-linked immunosorbent assay and multiplex opsonophagocytosis assay. Results: Including 63 patients, both groups showed an initial increase in the geometric mean titers of opsonophagocytic activity and the geometric mean concentrations of serotype-specific IgG levels after one month, followed by a decline at 3 and 5 years, particularly for serotypes 1, 14, 18C, and 19A. Despite the decline, global protection was maintained for 5 years, although global response decreased. The two arms did not show significant differences in immunogenicity nor in factors such as vaccination timing, age, cancer type, or chemotherapy regimen. Conclusion Vaccination timing is not a significant factor for the immunogenicity of PCV13 in cancer patients undergoing adjuvant chemotherapy. Global protection against pneumococcal infection was sustained for > 5 years, and global response remained in over half of patients.

Objective: This study was performed to evaluate the efficacy and safety of lurasidone (160 mg/day) compared to quetiapine XR (QXR; 600 mg/day) in the treatment of acutely psychotic patients with schizophrenia. Methods: Patients were randomly assigned to 6 weeks of double-blind treatment with lurasidone 160 mg/day (n=105) or QXR 600 mg/day (n=105). Primary efficacy measure was the change from baseline to week 6 in Positive and Negative Syndrome Scale (PANSS) total score and Clinical Global Impressions severity (CGI-S) score. Adverse events, body measurements, and laboratory parameters were assessed. Results: Lurasidone demonstrated non-inferiority to QXR on the PANSS total score. Adjusted mean±standard error change at week 6 on the PANSS total score was -26.42±2.02 and -27.33±2.01 in the lurasidone and QXR group, respectively. The mean difference score was -0.91 (95% confidence interval -6.35–4.53). The lurasidone group showed a greater reduction in PANSS total and negative subscale on week 1 and a greater reduction in end-point CGI-S score compared to the QXR group. Body weight, body mass index, and waist circumference in the lurasidone group were reduced, with significantly lower mean change compared to QXR. Endpoint changes in glucose, cholesterol, triglycerides, and low-density lipoprotein levels were also significantly lower. The most common adverse drug reactions with lurasidone were akathisia and nausea. Conclusion Lurasidone 160 mg/day was found to be non-inferior to QXR 600 mg/day in the treatment of schizophrenia with comparable efficacy and tolerability. Adverse effects of lurasidone were generally tolerable, and beneficial effects on metabolic parameters can be expected.

Purpose: Advances in chemotherapeutic and targeted agents have increased pathologic complete response (pCR) rates after neoadjuvant systemic therapy (NST). Vacuum-assisted biopsy (VAB) has been suggested to accurately evaluate pCR. This study aims to confirm the non-inferiority of the 5-year disease-free survival of patients who omitted breast surgery when predicted to have a pCR based on breast magnetic resonance imaging (MRI) and VAB after NST, compared with patients with a pCR who had undergone breast surgery in previous studies. Methods The Omission of breast surgery for PredicTed pCR patients wIth MRI and vacuumassisted bIopsy in breaST cancer after neoadjuvant systemic therapy (OPTIMIST) trial is a prospective, multicenter, single-arm, non-inferiority study enrolling in 17 tertiary care hospitals in the Republic of Korea. Eligible patients must have a clip marker placed in the tumor and meet the MRI criteria suggesting complete clinical response (post-NST MRI size ≤ 1 cm and lesion-to-background signal enhancement ratio ≤ 1.6) after NST. Patients will undergo VAB, and breast surgery will be omitted for those with no residual tumor. Axillary surgery can also be omitted if the patient was clinically node-negative before and after NST and met the stringent criteria of MRI size ≤ 0.5 cm. Survival and efficacy outcomes are evaluated over five years.Discussion: This study seeks to establish evidence for the safe omission of breast surgery in exceptional responders to NST while minimizing patient burden. The trial will address concerns about potential undertreatment due to false-negative results and recurrence as well as improved patient-reported quality of life issues from the omission of surgery. Successful completion of this trial may reshape clinical practice for certain breast cancer subtypes and lead to a safe and less invasive approach for selected patients.

Targetoid hemosiderotic nevus (THN) is a rare variant of melanocytic nevus, characterized by a sudden development of a targetoid ecchymotic halo around a pre-existing nevus. THN clinically raises concern for malignant transformation due to its abrupt change in color and size. THN should be distinguished from other diseases showing a peripheral halo, including targetoid hemosiderotic hemangioma, halo nevus, and Meyerson nevus. Dermoscopy can help clinicians to differentiate THN from these diseases. The typical dermoscopic features of THN are known to be divided into two distinctive areas: the central melanocytic area and the peripheral ecchymotic area. In our case, dermoscopy revealed a novel bull’s eye pattern composed of a central area with characteristic features of benign melanocytic nevus, an intermediated white circular ring, and a peripheral milky red area. When a sudden change occurs in a pre-existing nodule showing targetoid features, dermoscopy should be considered before conducting a biopsy or surgical intervention.

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.

Background/Aims: Complementary and alternative medicine (CAM) is prevalent in East Asia. However, information on CAM in East Asian patients with inflammatory bowel disease (IBD) is scarce. We aimed to profile the prevalence and pattern of CAM use among East Asian IBD patients and to identify factors associated with CAM use. We also compared physicians’ perspectives on CAM. Methods: Patients with IBD from China, Japan, and South Korea were invited to complete questionnaires on CAM use. Patient demographic and clinical data were collected. Logistic regression analysis was applied for predictors of CAM use. Physicians from each country were asked about their opinion on CAM services or products. Results: Overall, 905 patients with IBD participated in this study (China 232, Japan 255, and South Korea 418). Approximately 8.6% of patients with IBD used CAM services for their disease, while 29.7% of patients sought at least 1 kind of CAM product. Current active disease and Chinese or South Korean nationality over Japanese were independent predictors of CAM use. Chinese doctors were more likely to consider CAM helpful for patients with IBD than were Japanese and South Korean doctors. Conclusions In 8.6% and 29.7% of East Asian patients with IBD used CAM services and products, respectively, which does not differ from the prevalence in their Western counterparts. There is a significant gap regarding CAM usage among different Asian countries, not only from the patients’ perspective but also from the physicians’ point of view.

Purpose: To evaluate the role of postmastectomy radiation therapy (PMRT) in patients with node-negative breast cancer of 5cm or larger tumors undergoing mastectomy Materials and Methods: Medical records of 274 patients from 18 institutions treated with mastectomy between January 2000 and December 2016 were retrospectively reviewed. Among these, 202 patients underwent PMRT, while 72 did not. Two hundred and forty-one patients (88.0%) received systemic chemotherapy, and 172 (62.8%) received hormonal therapy. Patients receiving PMRT were younger, more likely to have progesterone receptor-positive tumors, and received adjuvant chemotherapy more frequently compared with those without PMRT (p <0.001, 0.018, and <0.001, respectively). Other characteristics were not significantly different between the two groups. Results: With a median follow-up of 95 months (range, 1-249), there were 9 locoregional recurrences, and 20 distant metastases. The 8-year locoregional recurrence-free survival rates were 98.0% with PMRT and 91.3% without PMRT (p=0.133), and the 8-year disease-free survival (DFS) rates were 91.8% with PMRT and 73.9% without PMRT (p=0.008). On multivariate analysis incorporating age, histologic grade, lymphovascular invasion, hormonal therapy, chemotherapy, and PMRT, the absence of lymphovascular invasion and the receipt of PMRT were associated with improved DFS (p=0.025 and 0.009, respectively). Conclusion Locoregional recurrence rate was very low in node-negative breast cancer of 5cm or larger tumors treated with mastectomy regardless of the receipt of PMRT. However, PMRT was significantly associated with improved DFS. Further investigation is needed to confirm these findings.

Background: Lichenoid drug eruption (LDE) is a relatively rare form of cutaneous drug eruption and that resembles lichen planus on a clinical and histological basis. Although there are some studies on histopathological findings of LDE, studies on clinical findings of LDE are limited. Objective: To investigate the clinical and histopathologic findings and prognosis of LDE. Methods: We retrospectively investigated the clinicopathologic findings of LDE patients who visited Kosin University Gospel Hospital between 1990 and 2020. Results: This study included 44 LDE patients (male:female=1.4:1). The most common causative drug was anti-tuberculous drugs (52.3%), followed by 5-fluorouracil (11.4%), and captopril (9.1%). There were pruritic erythematous scaly or lichenoid patches and plaques in all cases. The most frequently involved sites were trunk and extremities. Notably, 15 cases (34.1%) involving the scalp and 3 cases (6.8%) involving the oral mucosa. Treatment modalities included oral, topical corticosteroid, and oral antihistamines. Among 44 cases, 28 patients discontinued the causative agent, and 16 patients continued to use it after diagnosis of LDE. The mean duration of treatment for patients who discontinued or did not discontinue the causative drugs was 4, 10 weeks, respectively. The most commonly observed histopathologic findings were superficial and deep perivascular infiltration of inflammatory cells (100.0%) and eosinophil infiltration (93.2%). Conclusion LDE can be differentiated from idiopathic lichen planus by clinicopathologic findings. LDE appears to be a mild form of drug eruption in which symptoms can be controlled with conservative treatment, even without the cessation of causative drugs for the treatment of the underlying disease.