Dual-wavelength pumped latticed Fermi-Pasta-Ulam recurrences in nonlinear Schrödinger equation

We show that the nonlinear stage of the dual-wavelength pumped modulation instability(MI)in nonlinear Schrödinger equation(NLSE)can be effectively analyzed by mode truncation methods.The resulting complicated heteroclinic structure of instability unveils all possible dynamic trajectories of nonlinear waves.Significantly,the latticed-Fermi-Pasta-Ulam recurrences on the modulated-wave background in NLSE are also investigated and their dynamic trajectories run along the Hamiltonian contours of the heteroclinic structure.It is demonstrated that there has much richer dynamic behavior,in contrast to the nonlinear waves reported before.This novel nonlinear wave promises to inject new vitality into the study of MI.

Do the expressions of gap junction gene connexin messenger RNA in noncancerous liver remnants of patients with hepatocellular carcinoma correlate with postoperative recurrences?

AIM: To investigate whether the changes of gap junction gene connexin messenger RNA in the noncancerous liver tissue of patients with hepatocellular carcinoma (HCC) could play a significant role in its postresection recurrence.METHODS: Seventy-nine consecutive patients having undergone curative resection for HCC entered this study.Using a reverse-transcription polymerase chain reaction (RT-PCR)-based assay, connexin (Cx) 26, connexin (Cx)32 and connexin (Cx) 43 mRNAs were determined prospectively in noncancerous liver tissues from these 79 patients and in the liver tissues from 15 controls. The correlations between connexin mRNA expression and the clinicopathological variables and outcomes (tumor recurrence and recurrence related mortality) were studied.RESULTS: Compared with liver tissues of control patients,the expression of Cx 32 mRNA in noncancerous liver tissues was significantly lower (mean: 0.715 vscontrol 1.225,P＜0.01), whereas the decreased Cx 26 mRNA (mean:0.700 vs of control 1.205,P＞0.05) and increased Cx 43 mRNA (mean: 0.241 vscontrol 0.100, P＞0.05) had no statistical significance. We defined the value of Cx 32 mRNA or Cx 26mRNA below 0.800 as a lower value. By multivariate analysis for noncancerous livers, a lower value of Cx 32 mRNA correlated significantly with a risk of HCC recurrence and recurrence-related mortality. The lower value of Cx 26 mRNA did not correlate with recurrence and mortality. The increased value of Cx43 mRNA also did not correlate with postoperative recurrence and recurrence-related mortality. By multivariate analysis, other significant predictors of HCC recurrence included vascular permeation, cellular dedifferentiation, and less encaps-ulation. The other significant parameter of recurrence related mortality was vascular permeation.CONCLUSION: The decreased expression of Cx 32 mRNA in noncancerous liver tissues plays a significant role in the prediction of postoperative recurrence of HCC.

On the multiplicity of binary recurrences

Let A∈N,B∈Z with gcd(A,B)=1,B{-1,0,1}. For the binary recurrence (Lucas sequence) of the form u 0=0, u 1=1, u n+2 =Au n+1 +Bu n, let N 1(A,B,k) be the number of the terms n of |u n|=k, where k∈N. In this paper, using a new result of Bilu, Hanrot and Voutier on primitive divisors, we proved that N 1(A,B,k)≤1 except N 1(1,-2,1)=5[n=1,2,3,5,13], N 1(1,-3,1)=3, N 1(1,-5,1)=3,N 1(1,B,1)=2(B{-2,-3,-5}), N 1(12,-55,1)=2, N 1(12,-377,1)=2, N 1(A,B,1)=2(A 2+B=±1, A>1), N 1(1,-2,3)=2, N 1(A,B,A)=2(A 2+2B=±1,A>1. For Lehmer sequence, we got a similar result. In addition, we also obtained some applications of the above results to some Diophantime equations.

Mechanisms and clinical significance of early recurrences of atrial arrhythmias after catheter ablation for atrial fibrillation

Early recurrence of atrial arrhythmias(ERAA) after ablation is common and strongly predicts late recurrences and ablation failure. However, since arrhythmia may eventually resolve in up to half of patients with ERAA, guidelines do not recommend immediate reintervention for ERAA episodes occurring during a 3-mo postablation blanking period. Certain clinical demographic, electrophysiologic, procedural, and ERAA-related characteristics may predict a higher likelihood of longterm ablation failure. In this review, we aim to discuss potential mechanisms of ERAA, and to summarize the clinical significance, prognostic implications, and treatment options for ERAA.

Scattered and rapid intrahepatic recurrences after radio frequency ablation for hepatocellular carcinoma

AIM： To evaluate a series of patients with hepatocellular carcinoma （HCC） treated with several different protocols and devices. METHODS： We treated 138 patients [chronic hepatitis/ liver cirrhosis （Child-Pugh A/B/C）, 3/135 （107/25/3）] with two different devices and protocols： cool-tip needle [initial ablation at 60 W （standard method） （n = 37） or at 40 W （modified method） （n = 28）] or; ablation with a LeVeen needle using a standard single-step, full expansion （single-step） method （n = 39） or a multi-step, incremental expansion （multi-step） method. RESULTS： Eleven patients experienced rapid and scattered recurrences 1 to 7 mo after the ablation. Nine patients were treated by the cool-tip original protocol （60 W） （9/37 = 24%） and the other two by the LeVeen single-step method （2/39 = 5%）. The location of the recurrence was surrounding and limited to the site of ablation segment in three cases, and spread over one Iobule or both Iobules in the other eight cases. There was no recurrence in the patients treated with the modified cool-tip modified method （40 W） or the LeVeen multi-step method. CONCLUSION： There is a risk of rapid and scattered recurrence after RFA, especially when the standard cool- tip procedure is used. Because such recurrence would worsen the prognosis, we recommend that modified protocols for the cool-tip and LeVeen needle methods should be used in clinical practice.

Radiofrequency Ablation for Postoperative Recurrences of Intrahepatic Cholangiocarcinoma

Objective: Most recurrent intrahepatic cholangiocarcinoma (RICC) lost the opportunity of radical resection while most nonsurgical management failed to prolong patients’ survival. The efficacy and safety of radiofrequency ablation (RFA) as a local treatment for recurrent hepatocellular carcinoma have been confirmed by many clinical studies. The purpose of this study was to evaluate the efficacy, long-term survival and complications of RFA for RICC. Methods: A total of 12 patients with 19 RICCs after radical resection were included in this study. The tumors were 1.9–6.8 cm at the maximum diameter (median, 3.2±1.6 cm). All patients were treated with ultrasound guided RFA. There were two RFA approaches including percutaneous and open. Results: A total of 18 RFA treatment sessions were performed. Ablation was successful (evaluated by 1-month CT after the initial RFA procedure) in 18 (94.7%) of 19 tumors. By a median follow-up period of 29.9 months after RFA, 5 patients received repeated RFA because of intrahepatic lesion recurrence. The median local recurrence-free survival period and median event-free survival period after RFA were 21.0 months and 13.0 months, respectively. The median overall survival was 30 months, and the 1- and 3-year survival rates were 87.5% and 37.5%, respectively. The complication rate was 5.6% (1/18 sessions). The only one major complication was pleural effusion requiring thoracentesis. Conclusion: This study showed RFA may effectively and safely manage RICC with 3-year survival of 37.5%. It provides a treatment option for these RICC patients who lost chance for surgery.

Surgical outcomes in inferior recurrences of rhegmatogenous retinal detachment

AIM:To analyze the anatomical and functional outcomes in the inferior recurrences of rhegmatogenous retinal detachment(RRD)depending on the surgical approach.METHODS:Eighty-one eyes of 81 patients(47 males and 34 females with a mean age of 54.8±14.1y)who demonstrated at least one inferior recurrence of RRD were included in this retrospective study.All patients were categorized as having received either circular scleral buckling(SB),pars plana vitrectomy(PPV),a combination of SB and PPV(SB+PPV),PPV with retinotomy(PPV+RT),or PPV+RT and short-term postoperative perfluorocarbon liquid tamponade(PPV+RT+pPFCL).All cases were followed up until successful retinal reattachment or third recurrence.The primary outcome measures were the achievement of the surgical goal without recurrence of RRD and bestcorrected visual acuity(BCVA).RESULTS:After the treatment of the first recurrence,the recurrence rate in the PPV+SB group was statistically significantly lower than that of the PPV(P=0.0012),PPV+RT(P=0.028),or PPV+RT+pPFCL(P=0.047)group.There was no statistically significant difference between PPV+SB,PPV+RT,and PPV+RT+pPFCL groups in the recurrence rate after treatment of the second recurrence(42 eyes).However,there was a statistically significant(P=0.016)trend towards a decrease of recurrence rate after PPV+RT+pPFCL.There was no statistically significant improvement of BCVA in either study group(P>0.05)after both first and second recurrence surgery.The mean time follow-up was 109.0±91.0d before the first recurrence and 210.0±186.6d between previous surgery at second recurrence.CONCLUSION:Patients with first inferior recurrence of RRD may benefit from SB as an adjunct to PPV.RT and short-term pPFCL tamponade in the second recurrence may allow better anatomical outcomes,however,without functional improvement.

Endoscopy-based management decreases the risk of postoperative recurrences in Crohn's disease

AIM: To investigate whether an endoscopy-based management could prevent the long-term risk of postoperative recurrence.METHODS: From the pathology department database, we retrospectively retrieved the data of all the patients operated on for Crohn’s disease (CD) in our center (1986-2015). Endoscopy-based management was defined as systematic postoperative colonoscopy (median time after surgery = 9.5 mo) in patients with no clinical postoperative recurrence at the time of endoscopy.RESULTS: From 205 patients who underwent surgery, 161 patients (follow-up > 6 mo) were included. Endoscopic postoperative recurrence occurred in 67.6%, 79.7%, and 95.5% of the patients, respectively 5, 10 and 20 years after surgery. The rate of clinical postoperative recurrence was 61.4%, 75.9%, and 92.5% at 5, 10 and 20 years, respectively. The rate of surgical postoperative recurrence was 19.0%, 38.9% and 64.7%, respectively, 5, 10 and 20 years after surgery. In multivariate analysis, previous intestinal resection, prior exposure to anti-TNF therapy before surgery, and fistulizing phenotype (B3) were postoperative risk factors. Previous perianal abscess/fistula (other perianal lesions excluded), were predictive of only symptomatic recurrence. In multivariate analysis, an endoscopy-based management (n = 49/161) prevented clinical (HR = 0.4, 95%CI: 0.25-0.66, P < 0.001) and surgical postoperative recurrence (HR = 0.30, 95%CI: 0.13-0.70, P = 0.006).CONCLUSION: Endoscopy-based management should be recommended in all CD patients within the first year after surgery as it highly decreases the long-term risk of clinical recurrence and reoperation.

Evaluation of an Orally Administered Multistrain Probiotic Supplement in Reducing Recurrences Rate of Bacterial Vaginosis: A Clinical and Microbiological Study

Background: Bacterial vaginosis (BV) is the most common urogenital disease in women, affecting about 19% - 24% of them in reproductive ages annually and after treatment, a single recurrence or more may occur in up to 58% of women within 12 months. Objective: The aim was to evaluate the effectiveness of a new orally administered food supplement, containing different probiotic strains, on women of childbearing age after the antibiotic treatment when compared with no probiotic intake. Methods: A prospective study was undertaken on 62 patients with BV. All patients were cured with metronidazole vaginal formulations (5 g of 0.75% gel once daily for 5 days or 500 mg ovules once daily for 7 days), then after was offered the option of using a new an orally administered food supplement containing: Lactobacillus plantarum PBS067, Lactobacillus rhamnosus LRH020 and Bifidobacterium animalis lactis BL050, with a total viability of 3 × 109 CFU/capsule (Intimique®Femme). Among these women, 50 accepted to use the new orally food supplement, while 25 patients decided to use only metronidazole (control group). Results: The recurrence rate of BV after treatment with Intimique®Femme was about 16%, compared to 40% in the control group. The incidence of abnormal vaginal microbiota decreased in both groups, but it was significantly higher in the Intimique®Femme group at the end of treatment. Conclusion: This study showed that, in case of BV diagnosis, the complementary treatment of a strain-specific probiotic complex after antibiotics prophylaxis, is mandatory to reduce potential recurrences and cyclic use of further antibiotics.

Familial cardiac myxoma with multifocal recurrences:a case report and review of the literature

We report a case of myxoma with multiple recurrences in both the atrium and ventricle in a 26-year-old woman five years after the surgical removal of left atrial myxoma, Her 52-year-old mother had a similar medical history. To our knowledge, this was the first familial case who suffered multifocal cardiac myxoma recurrences without any sign of the myxoma complex. Based on our understanding of the mechanism of recurrence, the approaches to prevent the recurrence, and markers to predict recurrence, we propose that multifocal recurrences, as reported herein, may result from a combination of familial predisposition and multifocal onset. The hi-atrial surgical approach and transesophageal echocardiography are preferred for patients with recurrent cardiac myxomas, especially for those with multiple recurrences and familial myxoma. Immunological and genetic screenings may help to identify family members at risk for developing this disease.

Axillary Recurrences after Sentinel Node Surgery—Results over Ten Years in a University Hospital

Background: Sentinel node biopsy (SNB) was introduced at Ullevaal University Hospital in 2000. This article presents results from the first ten years use of the method. Material and Methods: A prospective registration of 2762 patients was made from 2000 through 2009. Results: The median follow-up time was 51 months. The overall detection rate was 93%. 36% of the patients with positive SNs had non-sentinel metastases. These were significantly associated with a macrometastatic SN and a primary tumour>20 mm. 18% of patients with sentinel metastasis≤2 mm had non-sentinel metastases. 14 patients with negative SN (0.7%) developed axillary recurrence. 32% with a preoperative diagnosis of ductal carcinoma in situ (DCIS) were upstaged to infiltrating carcinoma on final histology. None of the patients with pure DCIS had positive SNs. Conclusion: Few late events (0.7%) in SN negative axillas demonstrate the safety of the technique.

Characteristics of gut microbiota dysbiosis in patients with colorectal polyps

This editorial,inspired by a recent study published in the World Journal of Gastrointestinal Oncology,covers the research findings on microbiota changes in various diseases.In recurrent colorectal polyps,the abundances of Klebsiella,Parvimonas,and Clostridium increase,while those of Bifidobacterium and Lactoba-cillus decrease.This dysbiosis may promote the formation and recurrence of polyps.Similar microbial changes have also been observed in colorectal cancer,inflammatory bowel disease,autism spectrum disorder,and metabolic syndrome,indicating the role of increased pathogens and decreased probiotics in these conditions.Regulating the gut microbiota,particularly by increasing probiotic levels,may help prevent polyp recurrence and promote gut health.This microbial intervention strategy holds promise as an adjunctive treatment for patients with colorectal polyps.

Hepatocellular carcinoma recurrence after liver transplant:An Australian single-centre study

BACKGROUND Hepatocellular carcinoma(HCC)is a leading cause of cancer-related deaths worldwide.Liver transplantation(LT)offers the most effective treatment.HCC recurrence is the strongest risk factor that decreases post-LT survival in patients transplanted for HCC.The rate of HCC recurrence is generally reported as 8%-20%in the literature.Many predictors of HCC have already been researched,however,to our knowledge there are no published studies on this topic using Australian data.AIM To determine the rate and identify predictors of HCC recurrence in a contemporary Western Australian LT cohort.METHODS We performed a retrospective cohort study of all liver transplants in patients with HCC at Sir Charles Gairdner Hospital between 2006 and 2021.Data was collected from various health record databases and included recipient demographics,serum biochemistry,radiology,operation notes,explant histopathology and details of recurrence.Overall survival of HCC patients post-LT,stratified for recurrence,was calculated by Kaplan Meier analysis.Univariate and multivariate Cox regression was used to determine predictors of HCC recurrence post-LT.RESULTS Between 1/1/2006 and 12/31/2021,119 patients were transplanted with HCC.8.4%of subjects developed recurrent HCC after LT with median follow-up time of 5.4 years.The median time to recurrence was 2.9 years±0.75 years.When comparing baseline characteristics,a greater proportion of subjects with recurrence had common characteristics on explant histopathology,including>3 viable nodules(P=0.001),vascular invasion(P=0.003)and poorly differentiated HCC(P=0.03).Unadjusted survival curves showed lower 1-year,3-year,5-year and 10-year survival rates in subjects with HCC recurrence compared to those without HCC recurrence(90%vs 92%,70%vs 88%,42%vs 80%,14%vs 76%,respectively;log rank P<0.001).CONCLUSION HCC recurrence was low at 8.4%in this contemporary Australian cohort,however it significantly impacted post-LT survival.Further studies are required to confirm predictors of recurrence and improve recipient outcomes.

Convergence of COVID-19 and recurrent stroke:In-hospital mortality risks explored

This editorial comments on the article by Desai et al,which investigates the impact of coronavirus disease 2019(COVID-19)on in-hospital mortality among patients with recurrent stroke using data from the 2020 National Inpatient Sample.The findings reveal significantly higher mortality rates in COVID-19-positive patients compared to non-COVID-19 patients,particularly among middle-aged individuals,males,and ethnic minorities.This editorial explores the underlying mechanisms contributing to these outcomes and discusses the clinical implications for targeted management strategies in high-risk groups.The results emphasize the need for comprehensive approaches to mitigate the heightened risks faced by recurrent stroke patients during the COVID-19 pandemic.

Surgical resection of a recurrent retroperitoneal paraganglioma: A case report

BACKGROUND Paraganglioma(PGL)is a neuroendocrine tumor originating from paraganglia that can occur in various locations,such as the head,neck,chest,abdomen,and pelvis.Retroperitoneal PGLs are rare,and recurrent cases in this area are partic-ularly uncommon,posing considerable surgical complexities.Owing to their neu-roendocrine activity,PGLs are capable of secreting hormones like catecholamines,thereby presenting significant challenges in hemodynamic management during the perioperative period.CASE SUMMARY We report a 64-year-old man with a recurrent retroperitoneal PGL.The patient underwent retroperitoneal mass resection in 2013,with postoperative pathology revealing a PGL.Regular follow-up was not conducted until April 2024,when a computed tomography scan revealed a huge mass in the retroperitoneum,closely adjacent to the abdominal aorta.Laboratory examinations revealed elevated levels of catecholamines in the patient's blood serum.Upon admission,volume expan-sion and blood pressure(BP)monitoring were carried out for one week,with catecholamine levels reviewed and normalized.Adequate preoperative prepa-ration was conducted,including central venous access,arterial BP monitoring,and the preparation of vasoactive agents.During tumor resection,the patient ex-perienced acute,significant fluctuations in BP.The timely intervention of the anesthesiologist stabilized the BP,facilitating the successful resection of the tumor which was confirmed as a recurrent PGL.Postoperative follow-up revealed no evidence of tumor residual or recurrence.CONCLUSION PGL recurrence is rare but non-negligible.PGLs adjacent to major arteries com-plicate surgery,and perioperative hemodynamic stability demands meticulous attention.Core Tip:Recurrent retroperitoneal paragangliomas are infrequent but pose substantial surgical challenges,particularly when located adjacent to critical vascular structures such as the abdominal aorta.Effective perioperative management of he-modynamic fluctuations,driven by catecholamine secretion,requires meticulous preoperative planning,including volume expansion,blood pressure monitoring,and vasoactive agent preparation.Surgical intervention demands prompt and coordinated anesthetic support to stabilize hemodynamics,ensuring successful tumor resection.Given the potential for late recurrence,long-term follow-up is essential for early detection and management of asymptomatic recurrences.INTRODUCTION Paraganglioma(PGL)is a neuroendocrine tumor originating from paraganglia,which are associated with the autonomic nervous system[1].These tumors arise from chromaffin cells or similar cells capable of secreting catecholamines,such as adrenaline and noradrenaline.PGLs manifest in various anatomical locations,including the head,neck,chest,abdomen,and pelvis,and are characterized by neurosecretory and chief cells surrounded by prominent vascular stroma.Although typically benign,malignant forms of PGL are also recognized,and they may exhibit a tendency for recurrence or me-tastasis[2].PGLs located in the retroperitoneum are relatively uncommon and present greater surgical challenges because of their complex anatomical location near vital organs and major blood vessels.Their catecholamine-secreting nature further complicates the maintenance of hemodynamic stability during the perioperative period.In May 2024,a patient with recurrent retroperitoneal PGL was admitted to our hospital,and the details are reported below.

Risk factors,monitoring,and treatment strategies for early recurrence after rectal cancer surgery

Early recurrence(ER)following surgery for rectal cancer is a significant factor impacting patient survival rates.Tsai et al identified age,preoperative neoadjuvant therapy,length of hospital stay,tumour location,and pathological stage as factors influencing the risk of ER.Postoperative monitoring for ER should encompass a thorough medical history review,physical examination,tumour marker testing,and imaging studies.Additionally,noninvasive circulating tumour cell DNA testing can be utilized to predict ER.Treatment strategies may involve radical surgery,radiation therapy,chemotherapy,and immunotherapy.Through a comprehensive analysis of risk factors,the optimization of monitoring methods,and the development of personalized treatment strategies,it is anticipated that both the efficacy of treatment and the quality of life for rectal cancer patients with postoperative recurrence can be significantly improved.

Improving predictive accuracy of early recurrence in pancreatic ductal adenocarcinoma:Role of postoperative serum tumor markers

In a recent study by He et al,the nomogram integrates postoperative serum tumor markers such as carbohydrate antigen 19-9 and carcinoembryonic antigen,thereby improving the accuracy of identifying high-risk patients compared to relying solely on preoperative markers,which has significant implications for customizing adjuvant therapy and potentially improving outcomes for this aggressive form of cancer.However,the study’s single-center design and short follow-up period may limit the generalizability of its findings and potentially introduce reporting bias.Future studies could consider additional confounding factors,such as adjuvant chemotherapy and variations in surgical techniques,to improve the model’s accuracy.Furthermore,it would be valuable to validate the nomogram in broader,prospective cohorts and explore the inclusion of additional markers like circulating tumor DNA to refine further its predictive power and applicability across diverse patient populations.

Preliminary study on the clinical value of endoscopic stricturotomy in the treatment of stricturing Crohn's disease

BACKGROUND Crohn's disease(CD)frequently leads to intestinal strictures,which pose significant challenges due to their complexity and limited treatment options.While medications can address inflammatory strictures,they are largely ineffective for fibrotic and mixed strictures,often necessitating surgical intervention.However,surgery carries considerable risks,including bleeding,infection,anastomotic leaks,and postoperative restricture formation.Endoscopic treatment,particularly endoscopic stricturotomy,offers a minimally invasive alternative that bridges the gap between medication and surgery.AIM To investigate the safety and efficacy of stricturotomy under single-balloon enteroscopy in stricturing CD.METHODS Patients diagnosed with stricturing CD at The First People's Hospital of Changzhou from June 2020 to April 2024 were enrolled and underwent endoscopic stricturotomy(ES).Relevant clinical data of patients were collected retrospectively.Outcomes included success rate,remission time,complications,and follow-up interventions.This observational study was followed up postoperatively to observe patient remission and recurrence rates.RESULTS Seventeen endoscopic strictures were created in 11 patients,achieving a 100%immediate success rate without any serious complications.During the follow-up period,stricture recurrence was observed in two patients,resulting in an endoscopic reintervention rate of 18.2%.Additionally,two patients required subsequent surgical intervention,with a surgical treatment rate of 18.2%.One patient experienced bowel obstruction 18 months post-ES and was successfully managed with conservative treatment without surgical intervention.The remission duration after the initial ES treatment was 10.1±8.2 months,with a median remission time of 10 months.CONCLUSION ES is a safe and effective treatment for CD-related strictures and warrants further clinical promotion and application.

Predictive value of magnetic resonance imaging parameters combined with tumor markers for rectal cancer recurrence risk after surgery

BACKGROUND An increasing number of studies to date have found preoperative magnetic resonance imaging(MRI)features valuable in predicting the prognosis of rectal cancer(RC).However,research is still lacking on the correlation between preoperative MRI features and the risk of recurrence after radical resection of RC,urgently necessitating further in-depth exploration.AIM To investigate the correlation between preoperative MRI parameters and the risk of recurrence after radical resection of RC to provide an effective tool for predicting postoperative recurrence.METHODS The data of 90 patients who were diagnosed with RC by surgical pathology and underwent radical surgical resection at the Second Affiliated Hospital of Bengbu Medical University between May 2020 and December 2023 were collected through retrospective analysis.General demographic data,MRI data,and tumor markers levels were collected.According to the reviewed data of patients six months after surgery,the clinicians comprehensively assessed the recurrence risk and divided the patients into high recurrence risk(37 cases)and low recurrence risk(53 cases)groups.Independent sample t-test andχ2 test were used to analyze differences between the two groups.A logistic regression model was used to explore the risk factors of the high recurrence risk group,and a clinical prediction model was constructed.The clinical prediction model is presented in the form of a nomogram.The receiver operating characteristic curve,Hosmer-Lemeshow goodness of fit test,calibration curve,and decision curve analysis were used to evaluate the efficacy of the clinical prediction model.RESULTS The detection of positive extramural vascular invasion through preoperative MRI[odds ratio(OR)=4.29,P=0.045],along with elevated carcinoembryonic antigen(OR=1.08,P=0.041),carbohydrate antigen 125(OR=1.19,P=0.034),and carbohydrate antigen 199(OR=1.27,P<0.001)levels,are independent risk factors for increased postoperative recurrence risk in patients with RC.Furthermore,there was a correlation between magnetic resonance based T staging,magnetic resonance based N staging,and circumferential resection margin results determined by MRI and the postoperative recurrence risk.Additionally,when extramural vascular invasion was integrated with tumor markers,the resulting clinical prediction model more effectively identified patients at high risk for postoperative recurrence,thereby providing robust support for clinical decision-making.CONCLUSION The results of this study indicate that preoperative MRI detection is of great importance for predicting the risk of postoperative recurrence in patients with RC.Monitoring these markers helps clinicians identify patients at high risk,allowing for more aggressive treatment and monitoring strategies to improve patient outcomes.

Complete resection of recurrent anal canal cancer using endoscopic submucosal dissection and transanal resection: A case report

BACKGROUND Early anal canal cancer is frequently treated with endoscopic submucosal dis-section(ESD)to preserve anal function.However,if the lesion is in the anal canal,then significant difficulties such as bleeding and challenges associated with scope manipulation can arise.CASE SUMMARY A 70-year-old woman undergoing follow-up after transverse colon cancer surgery was diagnosed with anal canal cancer extending to the dentate line.The patient underwent a combination of ESD and transanal resection(TAR).The specimen was excised in pieces,which resulted in difficulty performing the pathological evaluation of the margins,especially on the anal side where TAR was performed and severe crushing was observed.Careful follow-up was performed,and local recurrence was observed 3 years postoperatively.Because the patient had super-ficial cancer without lymph node metastasis,local resection was performed again.The second treatment attempt was improved as follows:(1)TAR and ESD were performed appropriately based on the situation by the same physician;(2)A needle scalpel was used during TAR to prevent tissue crushing;and(3)The lesion borders were marked using ESD techniques before treatment.Complete resection was performed without complications.CONCLUSION Anal canal lesions can be safely and reliably removed when ESD and TAR are used appropriately.