Purpose: While MRI-based tumor regression grade (mrTRG) has shown promise in evaluating pathologic response to concurrent chemoradiotherapy (CCRT) in rectal cancer, its ability to predict pathologic complete response remains limited.This study aimed to enhance mrTRG’s diagnostic performance in predicting ypT0–1N0 status, a key factor in considering non-radical management after CCRT for locally advanced rectal cancer (LARC). Methods: This retrospective study included 430 patients with LARC who underwent radical resection following CCRT at a single referral hospital between April 2018 and September 2024. Multivariable logistic regression was used to identify predictive factors associated with achieving ypT0–1N0 status. The diagnostic performances of mrTRG1–2 alone and in combination with other factors were assessed by comparing sensitivity, specificity, positive-predictive value (PPV), negative-predictive value, and area under the curve (AUC). Results: Ninety-three patients (21.6%) achieved ypT0–1N0. In the multivariable analysis, fungating type, cT1–2, and mrTRG1–2 were independent predictors for ypT0–1N0. Integrating mrTRG with gross tumor type yielded the highest AUC of 0.689 among the combined models. For predicting ypT0–1N0, the combination of mrTRG and gross tumor type improved PPV (79.2% vs. 41.5% for mrTRG alone) while also demonstrating enhanced sensitivity compared with ycT0–1N0, the conventional MRI-based predictor (40.9% vs. 22.6%). Conclusion This study demonstrated that combining mrTRG and gross tumor type improved the PPV of mrTRG in predicting ypT0–1N0 after CCRT in LARC. Further studies are warranted to validate the role of gross tumor type in refining predictive systems for selecting candidates for non-radical treatment.

Stoma formation for fecal diversion is a common procedure in patients with various complicated conditions after colorectal surgery, such as anastomotic leakage. The singleincision laparoscopic approach for stoma creation offers several advantages, including a reduction in surgical wounds and related complications as well as optimal visualization of the surgical field. This video demonstrates a single-port–assisted diverting ileostomy in a 61-yearold man with anastomotic leakage following low anterior resection for advanced rectal cancer.

Stoma formation for fecal diversion is a common procedure in patients with various complicated conditions after colorectal surgery, such as anastomotic leakage. The singleincision laparoscopic approach for stoma creation offers several advantages, including a reduction in surgical wounds and related complications as well as optimal visualization of the surgical field. This video demonstrates a single-port–assisted diverting ileostomy in a 61-yearold man with anastomotic leakage following low anterior resection for advanced rectal cancer.

Stoma formation for fecal diversion is a common procedure in patients with various complicated conditions after colorectal surgery, such as anastomotic leakage. The singleincision laparoscopic approach for stoma creation offers several advantages, including a reduction in surgical wounds and related complications as well as optimal visualization of the surgical field. This video demonstrates a single-port–assisted diverting ileostomy in a 61-yearold man with anastomotic leakage following low anterior resection for advanced rectal cancer.

Purpose: Total mesorectal excision (TME) without lateral pelvic lymph node (LPN) dissection (LPND) is feasible in patients with mid/low rectal cancer showing a reduction in LPN size to ≤5 mm following neoadjuvant chemoradiotherapy (nCRT).We aimed to evaluate the clinical outcomes of selective LPNDs based on these criteria. Methods: Patients with mid/low rectal cancer and LPNs >5 mm before nCRT were included and classified based on nCRT response (post-nCRT LPN size ≤5 mm [responsive] vs. >5 mm [persistent]) and surgical procedure (TME alone vs. TME + LPND). In the responsive group, LPND was selectively performed only if morphologic predictors of LPN metastasis were present. Clinical outcomes were analyzed across subgroups. Results: Of 122 patients, 82 were in the responsive group. Within this group, 61 underwent TME alone and 21 underwent TME + LPND. No locoregional recurrence was observed in either subgroup of the responsive group, with similar systemic metastasis rates (13.1% vs. 14.3%, P > 0.99). The TME alone subgroup showed significantly smaller post-nCRT LPN sizes (1.7 ± 2.1 mm vs. 3.9 ± 1.8 mm, P < 0.001) and lower ycN positivity rates (31.1% vs. 71.4%, P = 0.001). Conclusion Selective LPND based on post-nCRT LPN size ≤5 mm and the absence of morphologic predictors of metastasis may serve as a feasible option for managing mid/low rectal cancer with enlarged LPNs, thereby optimizing local control and reducing unnecessary surgeries.

Mycophenolate mofetil (MMF) is usually prescribed with a reduced fixed dose in Asian kidney transplant recipients (KTRs). However, the clinical efficacy and safety of the fixed dose have not yet been investigated via therapeutic drug monitoring. We evaluated whether reduced fixed-dose MMF is an optimal dosing strategy to achieve the therapeutic target of mycophenolic acid (MPA) exposure in Korean KTRs. Methods: This open-label, prospective study enrolled 50 de novo KTRs prescribed with tacrolimus, corticosteroid, and fixed-dose MMF (1.0–1.5 g/day). The trough level (C0) and area under the curve (AUC0–12 hr) of MPA were measured at 1 and 24 weeks after kidney transplantation (KT). The relationship of body weight (BW)-adjusted MMF dose with MPA C0 and MPA AUC0–12 hr was assessed using linear regression analysis. Results: The initial fixed dose of MMF of 1.44 ± 0.16 g/day was adjusted in 24 patients (48.0%) and then reduced to a mean dose of 1.19 ± 0.31 g/day at 24 weeks after KT. Most patients (≥84.0%) attained the minimum required MPA C0 of 1.0 μg/mL and MPA AUC0–12 hr of 30 μg × hr/mL at 1 and 24 weeks. The BW-adjusted MMF dose demonstrated significant positive correlations with MPA C0 and MPA AUC0– 12 hr at 1 and 24 weeks after KT. Moreover, 14 patients (28.0%) reported MPA-related adverse events that were predictable based on MPA AUC0–12 hr (cutoff level, 46.4 μg × hr/mL). Conclusion: The current reduced fixed-dose MMF strategy can help achieve the therapeutic target of MPA exposure in tacrolimus- treated Korean KTRs during the early posttransplant period.

With the advancement of regenerative medicine, the demand for immune cell–derived blood components such as leukocytes is increasing. However, Article 3 of South Korea’s Blood Management Act prohibits financial compensation for blood donation. Moreover, nonconforming blood units, leftover specimens, and discarded leukocytes remain unavailable for commercial use. This study examined the current use of donated blood components, the potential application of leukocytes, regulatory barriers in producing reagent red blood cells, and donor compensation policies in countries such as the United States and Germany. We propose the establishment of a legal framework that enables the selective industrial use of cellular resources for therapeutic development, with safeguards in place to ensure adherence to ethical standards and the safety of donors. Such reforms could enhance the competitiveness of Korea’s bioindustry and expand access to novel therapies for patients with intractable diseases.

Complete mesocolic excision and central vascular ligation with D3 lymphadenectomy are important surgical principles for improving oncological outcomes in colon cancer. The cranial-first approach is a colonic mobilization–first approach to radical right hemicolectomy, which has several advantages, including early feasibility assessment, safe dissection from surrounding organs, preestablished inferior margin of lymph node dissection, and revelation of the tangible anatomy of the tributaries of the gastrocolic trunk. This video demonstrates the cranial-first approach to radical right hemicolectomy in a 66-year-old man with locally advanced cecal cancer.

Purpose: Anal wounds following hemorrhoidectomy can lead to severe pain and postoperative bleeding, impacting patient recovery and quality of life. Hyaluronic acid (HA) stimulates tissue regeneration and wound healing by accelerating cell migration and proliferation. This study aimed to investigate the differences in wound healing rate and completeness of recovery of perianal wounds topically treated with HA-soaked cotton in a murine model. Methods: Forty-eight 8-week-old Sprague-Dawley rats with perianal wounds created using a biopsy punch were divided into 2 groups: simple dressing with gauze (control) and topical HA-soaked cotton. A single application of HA-soaked cotton was administered after surgery. Wound healing rate and completeness of recovery were evaluated by measuring the healed area and conducting histological analyses. Results: The HA-cotton group exhibited a shorter complete wound healing duration compared to the control group (13.9 days vs. 16.4 days, P = 0.031). Differences in wound healing area between the 2 groups were greatest on postoperative day 2 (51.6% vs. 28.8%, P < 0.001). The HA-cotton group exhibited fewer cases of granulation tissue (2 vs. 5) or redness (0 vs.3) upon complete wound healing. Histologically, the HA-cotton group showed accelerated reepithelialization, rapid shift to lymphocyte-dominant inflammation, enhanced fibroblast proliferation, and increased collagen deposition compared to the control group. Conclusion Herein, topical application of HA-soaked cotton on perianal wounds in rats resulted in accelerated wound healing, particularly in the initial stages, and improved completeness of recovery, underscoring the potential of the topical application of HA-soaked cotton on hemorrhoidectomy wounds in human patients to improve wound healing.

Purpose: Managing recurrent inguinal hernias is complex, and choosing the right surgical approach (laparoscopic vs. open) is vital for patient outcomes. This study compared the outcomes of using the same vs. different surgical approaches for initial and subsequent hernia repairs. Methods: We retrospectively analyzed patients who underwent recurrent inguinal hernia repair at Seoul National University Bundang Hospital between January 2014 and May 2023. Patients were divided into the “concordant” and “discordant” groups, comprising patients who underwent same and different approaches in both surgeries, respectively. Preoperative baseline characteristics, index surgery data, postoperative outcomes, and recurrence rates were analyzed and compared. Results: In total, 131 patients were enrolled; the concordant and discordant groups comprised 31 (open, n = 19; laparoscopic, n = 12) and 100 patients (open to laparoscopic, n = 68; laparoscopic to open, n = 32), respectively. No significant differences were observed in the mean operation time (50.5 ± 21.7 minutes vs. 50.2 ± 20.0 minutes, P = 0.979), complication rates (6.5% vs. 14.0%, P = 0.356), or 36-month cumulative recurrence rates (9.8% vs. 9.8%; P = 0.865). The mean postoperative hospital stay was significantly shorter in the discordant than in the concordant group (1.8 ± 0.7 vs. 1.4 ± 0.6, P = 0.003). Conclusion Most recurrent inguinal hernia repairs were performed using the discordant surgical approach. Overall, concordance in the surgical approach did not significantly affect postoperative outcomes. Therefore, the selection of the surgical approach based on the patient’s condition and surgeon’s preference may be advisable.