Oxomollugin, an oxidized substance in mollugin, inhibited LPS-induced NF-κB activation via the suppressive effects on essential activation factors of TLR4 signaling.

Oxomollugin is a degraded product of mollugin and was found to be an active compound that inhibits LPS-induced NF-κB activation. In this study, we investigated the inhibitory activity of oxomollugin, focusing on TLR4 signaling pathway, resulting in NF-κB activation. Oxomollugin inhibited the LPS-induced association of essential factors for initial activation of TLR4 signaling, MyD88, IRAK4 and TRAF6. Furthermore, oxomollugin showed suppressive effects on LPS-induced modification of IRAK1, IRAK2 and TRAF6, LPS-induced association of TRAF6-TAK1/TAB2, and followed by IKKα/ß phosphorylation, which critical in signal transduction leading to LPS-induced NF-κB activation. The consistent results suggested that oxomollugin inhibits LPS-induced NF-κB activation via the suppression against signal transduction in TLR4 signaling pathway.The activities of oxomollugin reported in this study provides a deeper understanding on biological activity of mollugin derivatives as anti-inflammatory compounds.

Successful Pregnancy and Delivery After Frozen-thawed Embryo Transfer Following the Third Discontinuation of Tyrosine Kinase Inhibitor in a Woman with Chronic Myeloid Leukemia.

Assisted reproductive technology is a viable option for pregnant women with chronic myeloid leukemia. We herein report the case of a patient who underwent successful fertility treatment with frozen embryo preservation at 36 years of age, followed by embryo transfer at 39 years of age, thus resulting in pregnancy and delivery after a third discontinuation of tyrosine kinase inhibitors (TKI). Despite the difficulty of long-term TKI withdrawal, the patient's strong desire for a baby led to a successful pregnancy and delivery with no apparent deformities or abnormalities. Thus, our case highlights the importance of collaboration between reproductive medicine physicians and hematologists.

Investigation of biomarkers to predict outcomes in allogeneic hematopoietic stem cell transplantation.

BACKGROUND: Various biomarkers have been developed and evaluated to predict the prognosis and complications of allogeneic hematopoietic cell transplantation (HCT). Most previous studies conducted on different biomarkers evaluated single effects such as those associated with inflammation, immunology, iron metabolism, and nutrition, and only a few studies have comprehensively analyzed markers. OBJECTIVE: The study aimed to survey comprehensive multiple markers prior to HCT and extract those that significantly predict the outcomes. STUDY DESIGN: A prospective multicenter observational study was performed. (UMIN000013506) Patients undergoing HCT for hematologic diseases were consecutively enrolled. Besides the usual clinical biomarkers, serum samples for extra-clinical biomarkers were collected and cryopreserved before starting the conditioning regimen. A total of 32 candidate biomarkers were selected, 23 from hematology, biochemistry, immunology, nutrition, and iron metabolism, and 9 from composite markers. Based on the area under the curve (AUC) values for survival, promising biomarkers was extracted. Internal validation for these markers was applied based on bootstrap methods. Setting the cut-off values for them, log-rank test was applied and outcomes including overall survival (OS), relapse, and non-relapse mortality (NRM) were evaluated using multivariate analyses. Furthermore, detailed analysis including transplant-related complications and external validation were conducted focusing on C-reactive protein (CRP) to platelet (Plt) ratio. RESULTS: A total of 152 patients with hematologic malignancies were enrolled from April 2014 to March 2017. CRP, soluble interleukin-2 receptor (IL2R), CRP to albumin (Alb) ratio, CRP to Plt ratio, Plt to IL2R ratio, and IL2R to Alb ratio were identified as promising markers. Internal validation successfully confirmed their reliability of AUC and multivariate analysis demonstrated the statistical significance between the higher and the lower markers. Above all, a higher CRP to Plt ratio was significantly associated with a lower OS (hazard ratio [HR] 2.77; 95% confidence interval [CI] 1.30-5.91; P = 0.008) and higher non-relapse mortality rates (HR 2.79; 95%CI 1.14-6.80; P = 0.024) at 180 days. Furthermore, univariate analysis showed that a higher CRP to Plt ratio was significantly associated with a higher incidence of sinusoidal obstructive syndrome (P < 0.001) and bloodstream infection (P = 0.027). An external validation test confirmed the significance of the CRP to Plt ratio for these outcomes. CONCLUSION: The multicenter prospective observational study successfully identified significant biomarkers in patients with hematologic malignancies who received HCT. In particular, CRP to Plt ratio was identified as a novel and useful biomarker for predicting transplant outcomes. Further investigations are needed to validate the novel markers, analysis of the pathophysiology, and application to treatment settings other than HCT.

Objective Assessment of Physical Activity at Home Using a Novel Floor-Vibration Monitoring System: Validation and Comparison With Wearable Activity Trackers and Indirect Calorimetry Measurements.

BACKGROUND: The self-monitoring of physical activity is an effective strategy for promoting active lifestyles. However, accurately assessing physical activity remains challenging in certain situations. This study evaluates a novel floor-vibration monitoring system to quantify housework-related physical activity. OBJECTIVE: This study aims to assess the validity of step-count and physical behavior intensity predictions of a novel floor-vibration monitoring system in comparison with the actual number of steps and indirect calorimetry measurements. The accuracy of the predictions is also compared with that of research-grade devices (ActiGraph GT9X). METHODS: The Ocha-House, located in Tokyo, serves as an independent experimental facility equipped with high-sensitivity accelerometers installed on the floor to monitor vibrations. Dedicated data processing software was developed to analyze floor-vibration signals and calculate 3 quantitative indices: floor-vibration quantity, step count, and moving distance. In total, 10 participants performed 4 different housework-related activities, wearing ActiGraph GT9X monitors on both the waist and wrist for 6 minutes each. Concurrently, floor-vibration data were collected, and the energy expenditure was measured using the Douglas bag method to determine the actual intensity of activities. RESULTS: Significant correlations (P<.001) were found between the quantity of floor vibrations, the estimated step count, the estimated moving distance, and the actual activity intensities. The step-count parameter extracted from the floor-vibration signal emerged as the most robust predictor (r2=0.82; P<.001). Multiple regression models incorporating several floor-vibration-extracted parameters showed a strong association with actual activity intensities (r2=0.88; P<.001). Both the step-count and intensity predictions made by the floor-vibration monitoring system exhibited greater accuracy than those of the ActiGraph monitor. CONCLUSIONS: Floor-vibration monitoring systems seem able to produce valid quantitative assessments of physical activity for selected housework-related activities. In the future, connected smart home systems that integrate this type of technology could be used to perform continuous and accurate evaluations of physical behaviors throughout the day.

Association Between Aortic Wall Parameters on Multidetector Computed Tomography and Ruptured Plaques By Nonobstructive General Angioscopy.

BACKGROUND: Nonobstructive general angioscopy (NOGA) can identify vulnerable plaques in the aortic lumen that serve as potential risk factors for cardiovascular events such as embolism. However, the association between computed tomography (CT) images and vulnerable plaques detected on NOGA remains unknown. METHODS AND RESULTS: We investigated 101 patients (67±11 years; women, 13.8%) who underwent NOGA and contrast-enhanced CT before or after 90 days in our hospital. On CT images, the aortic wall thickness, aortic wall area (AWA), and AWA in the vascular area were measured at the thickest point from the 6th to the 12th thoracic vertebral levels. Furthermore, the association between these measurements and the presence or absence of NOGA-derived aortic plaque ruptures (PRs) at the same vertebral level was assessed. NOGA detected aortic PRs in the aortic lumens at 145 (22.1%) of the 656 vertebral levels. The presence of PRs was significantly associated with greater aortic wall thickness (3.3±1.7 mm versus 2.1±1.2 mm), AWA (1.33±0.68 cm2 versus 0.89±0.49 cm2), and AWA in the vascular area (23.2%±9.3% versus 17.2%±7.6%) (P<0.001 for all) on the CT scans compared with the absence of PRs. The frequency of PRs significantly increased as the aortic wall thickness increased. Notably, a few NOGA-derived PRs were detected on CT in near-normal intima. CONCLUSIONS: The presence of NOGA-derived PRs was strongly associated with increased aortic wall thickness, AWA, and AWA in the vascular area, measured using CT. NOGA can detect PRs in the intima that appear almost normal on CT scans.

Differential clinical impact of letermovir prophylaxis according to graft sources: a KSGCT multicenter retrospective analysis.

ABSTRACT: Clinically significant cytomegalovirus infection (csCMVi) is frequently observed after allogeneic hematopoietic stem cell transplantation (HSCT) and prophylaxis with letermovir is commonly adopted. However, the clinical benefit of letermovir prophylaxis according to graft sources has not been sufficiently elucidated. We retrospectively analyzed 2194 recipients of HSCT who were CMV-seropositive (236 with letermovir prophylaxis and 1958 without prophylaxis against CMV). csCMVi was significantly less frequent in patients with letermovir prophylaxis than in those without (23.7% vs 58.7% at 100 days after HSCT, P < .001) and the same trend was seen when recipients of bone marrow (BM), peripheral blood stem cell (PBSC), or cord blood (CB) transplantation were separately analyzed. In recipients of BM, nonrelapse mortality (NRM) was significantly lower in the letermovir group at 6 months after HSCT (5.0% vs 14.9%, P = .018), and the same trend was observed in recipients of PBSCs (14.7% vs 24.8%, P = .062); however, there was no statistical significance at 1 year (BM, 21.1% vs 30.4%, P = .67; PBSCs, 21.2% vs 30.4%, P = .096). In contrast, NRM was comparable between recipients of CB with and without letermovir prophylaxis throughout the clinical course (6 months, 23.6% vs 24.3%, P =.92; 1 year, 29.3% vs 31.0%, P = .77), which was confirmed by multivariate analyses. In conclusion, the impact of letermovir prophylaxis on NRM and csCMVi should be separately considered according to graft sources.

Multicenter prospective randomized controlled clinical trial comparing the pocket-creation method with and without single-clip traction of colonic endoscopic submucosal dissection.

BACKGROUND: The pocket-creation method (PCM) was developed to overcome the technical difficulties of endoscopic submucosal dissection (ESD), although opening the pocket remains challenging. We developed a novel technique of PCM with single-clip traction (PCM-CT), which uses a reopenable clip as a traction device to maintain stability during the procedure. No prospective study has compared the efficacy of PCM-CT and PCM. This study aimed to investigate the effectiveness of PCM-CT vs. PCM in a randomized controlled trial. METHODS: This randomized controlled clinical trial was conducted at four Japanese institutions. Patients with superficial colorectal neoplastic lesions were included following Japanese guidelines for colorectal cancer. Seven moderately experienced endoscopists performed the ESD procedures using either PCM-CT or PCM. RESULTS: 100 patients were enrolled in the study. Compared with PCM, PCM-CT achieved significantly faster mean (SD) dissection speed (21.4 [10.8] vs. 27.0 [14.5] mm2/min [95%CI 0.5 to 10.7], P = 0.03), and reduced the mean procedure time (81.8 [57.9] vs. 64.8 [47.6] minutes [95%CI -38.2 to 4.3], P = 0.12) and pocket-opening time (37.8 [33.0] vs. 30.0 [28.9] minutes [95%CI -20.2 to 4.6], P = 0.22). En bloc and R0 resection rates were not significantly different between the two groups (100% vs. 100%, P >0.99; 100% vs. 96%, P = 0.50, respectively). No significant differences were observed in adverse events between the two groups. CONCLUSION: ESD facilitated by the novel PCM-CT method appeared to be significantly faster than PCM. Both methods achieved high R0 resection rates.

Relapse of Ulcerative Colitis with Immune Thrombocytopenia and Pyoderma Gangrenosum Subsequent to Receiving COVID-19 Vaccination.

This case illustrates the complex interactions of the immune responses after vaccination and highlights their potential connections to various autoimmune conditions. A 22-year-old man with quiescent ulcerative colitis (UC) presented with abdominal pain, rectal bleeding, and thrombocytopenia 7 days after receiving the third coronavirus disease 2019 mRNA vaccination. Laboratory data confirmed the diagnosis of immune thrombocytopenia. High-dose intravenous immunoglobulin administration boosted the patient's platelet count. Simultaneously, colonoscopy revealed that his UC had relapsed. Although salazosulfapyridine briefly improved his symptoms, his stool frequency worsened one week later. The patient also developed pyoderma gangrenosum. Subsequent treatment with infliximab notably improved both pyoderma gangrenosum and UC.

Comparison of standardized prophylactic high-dose and intrathecal methotrexate for DLBCL with a high risk of CNS relapse.

The efficacy of high-dose methotrexate (HD-MTX) for central nervous system (CNS) relapse prophylaxis in patients with high-risk diffuse large B-cell lymphoma (DLBCL) is controversial. We compared the prophylactic effects of HD-MTX and intrathecal methotrexate (IT-MTX) on CNS relapse in high-risk DLBCL, in a multicenter retrospective study. A total of 132 patients with DLBCL at high risk of CNS relapse who received frontline chemotherapy and IT-MTX from 2003 to 2013 (n = 34) or HD-MTX from 2014 to 2020 (n = 98) were included. After a median follow-up of 52 months (range: 9-174), 11 patients had isolated CNS relapse: six (6.1%) in the HD-MTX group and five (14.7%) in the IT-MTX group. The median time until CNS relapse was 38 months (range: 11-122), and the cumulative incidence of CNS relapse at 3 years was 3.9% in the HD-MTX group and 6.1% in the IT-MTX group (P = 0.93). Similar results were obtained after adjusting for background factors using propensity score-matched analysis (4.5% HD-MTX vs. 7.6% IT-MTX, P = 0.84). The CNS relapse rate in HD-MTX-treated patients was equivalent to that in IT-MTX patients, demonstrating that HD-MTX was not superior to IT-MTX in preventing CNS relapse.

Echocardiographic Findings of Malignant Lymphoma with Cardiac Involvement: A Single-center Retrospective Observational Study.

Objective Although malignant lymphoma (ML) can occur in every organ, diagnosing cardiac involvement without cardiac manifestations is difficult. We therefore investigated the incidence of cardiac involvement in ML in our hospital and clarified the transthoracic echocardiography (TTE) findings of cardiac involvement. Methods Patients with ML referred to our hospital between January 2013 and December 2019 were retrospectively reviewed. Patients During the study period, 453 patients were identified. The mean age was 64.9 years old, and 54% of the patients were men. Results Diffuse large B-cell lymphoma (DLBCL) was the most common lymphoma, followed by follicular lymphoma. Of the 453 patients, 394 (87.0%) underwent TTE at the initial diagnosis or during the clinical course. The performance rates of TTE in DLBCL, Hodgkin lymphoma, and mantle cell lymphoma were above 90%. Cardiac involvement was detected in 6 (five with DLBCL and one with B-cell lymphoma) (1.5%) of the 394 patients who underwent TTE. The involved lesions of the heart varied, and five patients had pericardial effusion. Five patients had a preserved left ventricular ejection fraction. All patients were treated with chemotherapy, and some were treated with radiation and surgery. Conclusion Cardiac involvement was observed in six (1.5%) of the patients with ML who underwent TTE. B-cell lymphoma, especially DLBCL, is a common ML with cardiac involvement. Although five patients had pericardial effusion, the involved lesions of the heart were not uniform. TTE is a useful imaging modality to noninvasively and repeatedly evaluate the tumor characteristics, response to ML treatment, and cardiac function.

Prognostic significance of the CFA ratio for newly diagnosed acute myeloid leukemia: A multicenter retrospective study.

The CFA ratio, calculated using pretreatment C-reactive protein (CRP), fibrinogen, and albumin levels (CRP × fibrinogen/albumin), was previously reported to be a significant prognostic factor for acute myeloid leukemia (AML). This multicenter retrospective study evaluated the prognostic value of the CFA ratio in 328 adult patients with newly diagnosed AML from April 2000 to March 2018. The median age was 49.5 years (range, 15-75 years), and 60.7% of the population were males. According to the European LeukemiaNet (ELN) risk classification, 67 patients (20.4%) were in the favorable-risk group, 197 patients (60.1%) in the intermediate-risk group, and 58 patients (17.7%) in the adverse-risk group. The median CFA ratio was 1.07 (0-67.69). Based on the calculated cutoff CFA ratio of 1.44, the cohort included 176 and 152 patients with low and high CFA ratios, respectively. At a median follow-up of 91.2 months, the 7-year overall survival (OS) and disease-free survival (DFS) rates were 51.2% and 48.6%, respectively, in the overall cohort. The 7-year OS rates were 61.7% and 39.0% in the low and high CFA ratio groups, respectively (p < 0.001). The 7-year DFS rates were 58.1% and 37.0% in the low and high CFA ratio groups, respectively (p = 0.004). In univariate analysis, age ≥50 years, male sex, ELN risk class, and comorbidities were associated with poor OS. Age, ELN risk class, comorbidities, and high CFA ratio were associated with poor OS in multivariate analysis. Subgroup analysis revealed that the CFA ratio was significant in the intermediate and adverse ELN risk classes. These findings indicate the prognostic significance of the CFA ratio in AML.

Clinical significance of total nucleated cell count in bone marrow of patients with acute lymphoblastic leukemia who underwent allogeneic hematopoietic stem cell transplantation.

The clinical implications of recipient bone marrow nucleated cell count (NCC) prior to allogeneic hematopoietic stem cell transplantation (allo-HSCT) remain unknown. We conducted a multicenter retrospective study to evaluate the clinical significance of bone marrow NCC prior to allo-HSCT in patients with acute lymphoblastic leukemia. Patients who were in remission and underwent the initial allo-HSCT were included and stratified into high- and low-NCC groups using an NCC of 10 × 104/µL as the cut-off. The 3-year overall survival (OS), non-relapse mortality (NRM), and relapse rates for the high- and low-NCC groups were 51.2 vs. 84.5% (p < 0.001), 27.5 vs. 6.5% (p < 0.001), and 31.1 vs. 24.4% (p = 0.322), respectively. The high-NCC group had significantly poorer OS and higher NRM when compared with the low-NCC group. In summary, high recipient bone marrow NCC is associated with higher NRM and lower OS following allo-HSCT.

Association between aortic thrombi detected using non-obstructive general angioscopy and atrial fibrillation.

Atrial fibrillation (AF) is an independent risk factor for stroke and systemic embolism. Cardiogenic and aortogenic emboli are causes of stroke or systemic embolism. Non-obstructive general angioscopy (NOGA) can be used to diagnose aortic intimal findings, including thrombi and atherosclerotic plaques, but little is known about NOGA-derived aortic intimal findings in patients with AF. This study focused on aortic intimal findings in patients with AF and evaluated the association between AF and aortic thrombi detected using NOGA. We enrolled 283 consecutive patients with coronary artery disease who underwent NOGA of the aorta between January 2017 and August 2022. Aortic intimal findings were screened using NOGA after coronary arteriography. The patients were divided into two groups according to their AF history (AF, n = 50 and non-AF, n = 233). Patients in the AF group were older than those in the non-AF group. Sex, body mass index, and coronary risk factors were not significantly different between the two groups. In the NOGA findings, the presence of intense yellow plaques and ruptured plaques was not significantly different between the two groups. Aortic thrombi were more frequent in the AF group than in the non-AF group (92.0 vs. 71.6%, p < 0.001). Multivariate logistic regression found that AF was independently associated with aortic thrombi (odds ratio 3.87 [95% CI 1.28-11.6], p = 0.016). The presence of aortic thrombi observed using NOGA was associated with AF in patients with coronary artery disease. The roles of aortic thrombi as well as cardiogenic embolism may require clarification.

Impact of non-gated computed tomography on the timing of invasive strategy of patients with non-ST-elevation acute coronary syndrome.

Background: This study aimed to examine the clinical role of non-gated computed tomography (CT) in ruling out fatal chest pain in patients with non-ST-elevation acute coronary syndrome (NSTE-ACS), with a focus on the time of arrival at the hospital to coronary angiography (CAG) and peak creatine kinase (CK) levels. Methods: We retrospectively examined 196 NSTE-ACS patients who were admitted with urgently diagnosed NSTE-ACS and underwent percutaneous coronary intervention between March 2019 and October 2022. The patients were divided into three groups, namely, non-CT group, CT and defect- group, and CT and defect+ group, based on whether they underwent a CT scan and the presence or absence of perfusion defects on the CT image. Results: After the initial admission for NSTE-ACS, 40 patients (20.4%) underwent non-gated CT prior to CAG. Among these 40 patients, 27 had a perfusion defect on the CT scan. The incidence of contrast-induced nephropathy was not different among the three groups. The CT and defect+ group had a shorter arrival-to-CAG time than that of the non-CT group. In NSTE-ACS patients with elevated CK levels, the CT and defect+ group had lower peak CK levels than those in the non-CT group. Conclusion: NSTE-ACS patients with perfusion defects on non-gated CT had a shorter time from arrival to CAG, which might be associated with a lower peak CK. Non-gated CT might be useful for early diagnosis and early revascularization in the clinical setting of NSTE-ACS.

[Primary mediastinal large B-cell lymphoma complicated with myotonic dystrophy].

A 39-year-old woman with myotonic dystrophy (DM) presented with syncope and was diagnosed with primary mediastinal large B-cell lymphoma, clinical stage IA. PET-CT revealed an upper mediastinal mass with high FDG uptake (SUVmax, 14.8). She had muscle weakness associated with DM, but her performance status was preserved. She was treated with 6 cycles of dose-adjusted EPOCH-R therapy and localized irradiation for the residual mass, without severe adverse events or recurrence of syncope. Patients with DM should be monitored for cardiac events and muscle weakness when undergoing lymphoma treatment.

Gonadal Germ Cell Migration and Proliferation after Transfer in Developing Chicken Embryos.

A germline chimera is a useful model for developing and differentiating germ cells in vivo. Gonadal germ cells (GGCs) collected from chicken embryonic gonads may be used to produce germline chimeras as donor cells. However, the migratory and proliferative abilities of GGCs after transfer into recipient embryos are unclear. Here, the migratory and proliferative abilities of GGCs collected from 7-day-old White Leghorn embryos and fluorescently labeled were analyzed following transfer into the dorsal aorta of 2.5-day-old Rhode Island Red (RIR) embryos. Five days after transfer, the numbers of male and female GGCs were significantly higher in the RIR gonads than those in non-gonadal RIR organs when 50 GGCs were transferred per embryo. To analyze the temporal migration of GGCs in intermediate mesoderm, 50 GGCs were again transferred. The numbers of male and female GGCs in RIR gonads increased significantly from days 3 to 6 after transfer. To analyze GGC migration and proliferation in the gonads, a single GGC was transferred into 100 male and 100 female embryos. Five days after transfer, the frequencies of settled and proliferated GGCs were 37% (37/100) and 24% (24/100) in males, and 23% (23/100) and 8% (8/100) in females, respectively. Thus, GGCs are a heterogeneous cell population that may or may not have migratory and proliferative abilities. The heterogeneity of GGCs may be greater in females than that in males. When 50 GGCs were transplanted, almost all those present in embryos had settled and proliferated in the gonads and mesonephros. The migratory and proliferative abilities of GGCs in recipient gonads were considerably diverse in individual GGCs or between donor sexes.

Non-interventional Management of Asymptomatic Diminutive Choledocholithiasis Versus Endoscopic Extraction in Consecutive Patients.

BACKGROUND: Current guidelines recommend treating choledocholithiasis, regardless of symptoms or stone size, with endoscopic retrograde cholangiopancreatography (ERCP). However, asymptomatic choledocholithiasis, discovered incidentally on imaging, may carry a higher risk of ERCP-related adverse events, and some asymptomatic and diminutive stones may not cause biliary adverse events during extended follow-up. Therefore, we aimed to clarify the best treatment strategies for asymptomatic choledocholithiasis based on stone size. METHODS: We retrospectively identified patients with incidental imaging-found asymptomatic diminutive (≤ 4 mm) or non-diminutive (> 4 mm) choledocholithiasis and divided them into two groups: those who did not undergo ERCP and were treated when complications arose (on-demand group) and those who underwent ERCP before being symptomatic (intervention group). Adverse events were defined as any biliary or pancreatic complication related to ERCP or arising during observation or after intervention. The primary outcome was the adjusted overall adverse event-free survival using the propensity score-based matching weights method comparing the two groups of stone size. RESULTS: Among 148 patients identified (median follow-up period, 969 days), 68 had diminutive stones and 80 had non-diminutive stones. Of the 68 patients with diminutive stones, 51 were in the on-demand group and 17 in the intervention group. The overall adjusted adverse event-free survival was significantly higher in the on-demand group for diminutive stones (97.4% and 70.1%, respectively, at 3 years; p = 0.01). DISCUSSION: Patients with incidental imaging-detected asymptomatic diminutive choledocholithiasis may benefit from clinical observation, pursuing ERCP when symptoms develop.

Percutaneous endoscopic necrosectomy for walled-off necrosis in the retroperitoneal space of the elderly: A case report.

BACKGROUND: Walled-off necrosis (WON) is a late complication of acute pancreatitis possibly with a fatal outcome. Even for WON spreading to the retroperitoneal space, percutaneous endoscopic necrosectomy (PEN) can be an alternate approach to surgical necrosectomy, particularly for the older individuals or patients with poor condition because of WON. CASE SUMMARY: An 88-year-old man was admitted to our hospital with a jaundice. Endoscopic retrograde cholangiopancreatography (ERCP) was performed to improve jaundice; however, post-ERCP pancreatitis developed. The inflammation of pancreatitis spread widely from the right retroperitoneal cavity to the pelvis, and WON was formed 4 wk later. A percutaneous drainage tube was placed into the WON under computed tomography guidance. However, the drainage did not ameliorate clinical symptoms including fever, which assured less invasive necrosectomy. A metallic stent for the upper gastrointestinal (GI) tract was placed from the percutaneous drainage route. An upper GI endoscope was inserted into the inside of the WON through the metallic stent, and the necrotic tissues were bluntly removed with a snare forceps. Ten times of these necrosectomies resulted in the near-complete removal of necrotic tissues. These procedures consequently abated his fever and remarkable improvement in blood tests. CONCLUSION: PEN for WON occurring in the retroperitoneal space was safe and effective for very old individuals.