Combining prognostic value of serum carbohydrate antigen 19-9 and tumor size reduction ratio in pancreatic ductal adenocarcinoma

BACKGROUND Pancreatic ductal adenocarcinoma(PDAC)is a common cancer with increasing morbidity and mortality due to changes of social environment.AIM To evaluate the significance of serum carbohydrate antigen 19-9(CA19-9)and tumor size changes pre-and post-neoadjuvant therapy(NAT).METHODS This retrospective study was conducted at the Chongqing Key Laboratory of Translational Research for Cancer Metastasis and Individualized Treatment,Chongqing University Cancer Hospital.This study specifically assessed CA19-9 levels and tumor size before and after NAT.RESULTS A total of 156 patients who completed NAT and subsequently underwent tumor resection were included in this study.The average age was 65.4±10.6 years and 72(46.2%)patients were female.Before survival analysis,we defined the post-NAT serum CA19-9 level/pre-NAT serum CA19-9 level as the CA19-9 ratio(CR).The patients were divided into three groups:CR<0.5,CR>0.5 and<1 and CR>1.With regard to tumor size measured by both computed tomography and magnetic resonance imaging,we defined the post-NAT tumor size/pre-NAT tumor size as the tumor size ratio(TR).The patients were then divided into three groups:TR<0.5,TR>0.5 and<1 and TR>1.Based on these groups divided according to CR and TR,we performed both overall survival(OS)and disease-free survival(DFS)analyses.Log-rank tests showed that both OS and DFS were significantly different among the groups according to CR and TR(P<0.05).CR and TR after NAT were associated with increased odds of achieving a complete or near-complete pathologic response.Moreover,CR(hazard ratio:1.721,95%CI:1.373-3.762;P=0.006),and TR(hazard ratio:1.435,95%CI:1.275-4.363;P=0.014)were identified as independent factors associated with OS.CONCLUSION This study demonstrated that post-NAT serum CA19-9 level/pre-NAT serum CA19-9 level and post-NAT tumor size/pre-NAT tumor size were independent factors associated with OS in patients with PDAC who received NAT and subsequent surgical resection.

Tumor size discrepancy between endoscopic and pathological evaluations in colorectal endoscopic submucosal dissection

BACKGROUND Tumor size impacts the technical difficulty and histological curability of colorectal endoscopic submucosal dissection(ESD);however,the preoperative evaluation of tumor size is often different from histological assessment.Analyzing influential factors on failure to obtain an accurate tumor size evaluation could help prepare optimal conditions for safer and more reliable ESD.METHODS This was a retrospective study conducted at a single institution.A total of 377 lesions removed by colorectal ESD at our hospital between April 2018 and March 2022 were collected.We first assessed the difference in size with an absolute per-centage of the scaling discrepancy.Subsequently,we compared the clinicopatho-logical characteristics of the correct scaling group(>-33%and<33%)with that of the incorrect scaling group(<-33%or>33%),which was further subdivided into the underscaling group(-33%or less of the discrepancy)and overscaling group(33%or more of the discrepancy),respectively.As secondary outcome measures,parameters on size estimation were compared between the underscaling and correct scaling groups,as well as between the overscaling and correct scaling groups.Finally,multivariate analysis was performed in terms of the following relevant parameters on size estimation:Pathological size,location,and possible influential factors(P<0.1)in the univariate analysis.RESULTS The mean of absolute percentage in the scaling discordance was 21%,and 91 lesions were considered to be incorrectly estimated in size.The incorrect scaling was significantly remarkable in larger lesions(40 mm vs 28 mm;P<0.001)and less experience(P<0.001),and these two factors were influential on the underscaling(75 lesions;P<0.001).Conversely,compared with the correct scaling group,16 lesions in the overscaling group were significantly small(20 mm vs 28 mm;P<0.001),and the small lesion size was influential on the overscaling(P=0.002).CONCLUSION Lesions indicated for colorectal ESD tended to be underestimated in large tumors,but overestimated in small ones.This discrepancy appears worth understanding for optimal procedural preparation.

Radiofrequency ablation is an inferior option to liver resection for solitary hepatocellular carcinoma≤5 cm without cirrhosis:A population-based study with stratification by tumor size

Background:About 10%-20%of all individuals who develop hepatocellular carcinoma(HCC)do not have cirrhosis.Comparisons are rarely reported regarding the effectiveness of radiofrequency ablation(RFA)and liver resection(LR)in survival of HCC without cirrhosis and stratification by tumor size≤5 cm.Methods:We used the Surveillance,Epidemiology,and End Results(SEER)database and identified 1505 patients with a solitary HCC tumor≤5 cm who underwent RFA or LR during 2004-2015.Patients were classified into non-cirrhosis and cirrhosis groups and each group was categorized into three subgroups,according to tumor size(≤30 mm,31-40 mm,41-50 mm).Results:In patients without cirrhosis,LR showed better 5-year HCC cancer-specific survival than RFA in all tumor size subgroups(≤30 mm:82.51%vs.56.42%;31-40 mm:71.31%vs.46.83%;41-50 mm:74.7%vs.37.5%;all P<0.05).Compared with RFA,LR was an independent protective factor for HCC cancer-specific survival in multivariate Cox analysis[≤30 mm:hazard ratio(HR)=0.533,95%confidence interval(CI):0.313-0.908;31-40 mm:HR=0.439,95%CI:0.201-0.957;41-50 mm:HR=0.382;95%CI:0.159-0.916;all P<0.05].In patients with cirrhosis,for both tumor size≤30 mm and 31-40 mm groups,there were no significant survival differences between RFA and LR in multivariate analysis(all P>0.05).However,in those with tumor size 41-50 mm,LR showed significantly better 5-year HCC cancer-specific survival than RFA in both univariate(54.72%vs.23.06%;P<0.001)and multivariate analyses(HR=0.297;95%CI:0.136-0.648;P=0.002).Conclusions:RFA is an inferior treatment option to LR for patients without cirrhosis who have a solitary HCC tumor≤5 cm.

Critical prognostic value of the log odds of negative lymph nodes/tumor size in rectal cancer patients

BACKGROUND The number of negative lymph nodes(NLNs)and tumor size are associated with prognosis in rectal cancer patients undergoing surgical resection.However,little is known about the prognostic significance of the NLN count after adjusting for tumor size.AIM To assess the prognostic impact of the log odds of NLN/tumor size(LONS)in rectal cancer patients.METHODS Data of patients with stage I–III rectal cancer were extracted from the Surveillance,Epidemiology,and End Results Program database.These patients were randomly divided into a training cohort and a validation cohort.Univariate and multivariate Cox regression analyses were used to determine the prognostic value of the LONS.The optimal cutoff values of LONS were calculated using the"X-tile"program.Stratified analysis of the effect of LONS on cancer-specific survival(CSS)and overall survival(OS)were performed.The Kaplan-Meier method with the log-rank test was used to plot the survival curve and compare the survival data among the different groups.RESULTS In all,41080 patients who met the inclusion criteria were randomly divided into a training cohort(n=28775,70%)and a validation cohort(n=12325,30%).Univariate and multivariate analyses identified the continuous variable LONS as an independent prognostic factor for CSS[training cohort:Hazard ratio(HR)=0.47,95%confidence interval(CI):0.44–0.51,P<0.001;validation cohort:HR=0.46,95%CI:0.41-0.52,P<0.001]and OS(training cohort:HR=0.53,95%CI:0.49-0.56,P<0.001;validation cohort:HR=0.52,95%CI:0.42-0.52,P<0.001).The Xtile program indicated that the difference in CSS was the most significant for LONS of-0.8,and the cutoff value of-0.4 can further distinguish patients with a better prognosis in the high LONS group.Stratified analysis of the effect of the categorical variable LONS on CSS and OS revealed that LONS was also an independent predictor,independent of pN stage,pT stage,tumor-node-metastasis stage,site,age,sex,the number of examined lymph nodes,race,preoperative radiotherapy and carcinoembryonic antigen level.CONCLUSION LONS is associated with improved survival of rectal cancer patients independent of other clinicopathological factors.

Cone beam computed tomography-guided differences among registration methods for lung cancer and the effects of tumor position,treatment model,and tumor size on positioning errors

Objective To explore the differences in three different registration methods of cone beam computed tomography(CBCT)-guided down-regulated intense radiation therapy for lung cancer as well as the effects of tumor location,treatment mode,and tumor size on registration.Methods This retrospective analysis included 80 lung cancer patients undergoing radiotherapy in our hospital from November 2017 to October 2019 and compared automatic bone registration,automatic grayscale(t+r)registration,and automatic grayscale(t)positioning error on the X-,Y-,and Z-axes under three types of registration methods.The patients were also grouped according to tumor position,treatment mode,and tumor size to compare positioning errors.Results On the X-,Y-,and Z-axes,automatic grayscale(t+r)and automatic grayscale(t)registration showed a better trend.Analysis of the different treatment modes showed differences in the three registration methods;however,these were not statistically significant.Analysis according to tumor sizes showed significant differences between the three registration methods(P<0.05).Analysis according to tumor positions showed differences in the X-and Y-axes that were not significant(P>0.05),while the autopsy registration in the Z-axis showed the largest difference in the mediastinal and hilar lymph nodes(P<0.05).Conclusion The treatment mode was not the main factor affecting registration error in lung cancer.Three registration methods are available for tumors in the upper and lower lungs measuring<3 cm;among these,automatic gray registration is recommended,while any gray registration method is recommended for tumors located in the mediastinal hilar site measuring<3 cm and in the upper and lower lungs≥3 cm.

Is lymphatic invasion of microrectal neuroendocrine tumors an incidental event?:A case report

BACKGROUND A rectal neuroendocrine tumor(rNET)is a malignant tumor originating from neuroendocrine cells.Currently,tumor size is the primary basis for assessing tumor risk.CASE SUMMARY This article reports the case of a 46-year-old male patient who underwent a colonoscopy that found a 3 mm rectal polypoid bulge.The pathological examination of a sample collected with biopsy forceps revealed a neuroendocrine tumor.Further endoscopic submucosal dissection rescue therapy was used.The presence of lymphatic vessels indicated that the tumor had infiltrated the negative resection margin.The lesion was located in the distal rectum near the anal canal.Therefore,to ensure the patient’s quality of life,follow-up observation was conducted after full communication with the patient.No tumor recurrence or distant metastasis has been found during the 13-mo follow-up after surgery.CONCLUSION Despite the presence of lymphatic invasion and extremely small diameter rNETs in our case,this phenomenon may not imply a higher risk of distant lymph node and organ metastasis.

Goldilocks principle of minimally invasive surgery for gastric subepithelial tumors

BACKGROUND Minimally invasive surgery had been tailored to individual cases of gastric subepithelial tumors(SETs)after comparing the clinical outcomes of endoscopic resection(ER),laparoscopic resection(LR),and hybrid methods.AIM To study the use of Goldilocks principle to determine the best form of minimally invasive surgery for gastric SETs.METHODS In this retrospective study,194 patients of gastric SETs with high probability of surgical intervention were included.All patients underwent tumor resection in the operating theater between January 2013 and December 2021.The patients were divided into two groups,ER or LR,according to the tumor characteristics and the initial intent of intervention.Few patients in the ER group required further backup laparoscopic surgery after an incomplete ER.The patients who had converted open surgery were excluded.A logistic regression model was used to assess the associations between patient characteristics and the likelihood of a treatment strategy.The area under the curve was used to assess the discriminative ability of tumor size and Youden’s index to determine the optimal cut-off tumor size.RESULTS One-hundred ninety-four patients(100 in the ER group and 94 in the LR group)underwent tumor resection in the operating theater.In the ER group,27 patients required backup laparoscopic surgery after an incomplete ER.The patients in the ER group had small tumor sizes and shorter procedure durations while the patients in the LR group had large tumor sizes,exophytic growth,malignancy,and tumors that were more often located in the middle or lower third of the stomach.Both groups had similar durations of hospital stays and a similar rate of major postoperative complications.The patients in the ER group who underwent backup surgery required longer procedures(56.4 min)and prolonged stays(2 d)compared to the patients in the LR group without the increased rate of major postoperative complications.The optimal cut-off point for the tumor size for laparoscopic surgery was 2.15 cm.CONCLUSION Multidisciplinary teamwork leads to the adoption of different strategies to yield efficient clinical outcomes according to the tumor characteristics.

Clinical and pathological characteristics and prognosis of 132 cases of rectal neuroendocrine tumors

BACKGROUND Neuroendocrine tumors(NETs)frequently occur in the gastrointestinal tract,lung,and pancreas,and the rectum and appendix are the sites with the highest incidence.Epidemiology statistics show that an estimated 8000 people every year in the United States are diagnosed with NETs occurring in the gastrointestinal tract,including the stomach,intestine,appendix,colon,and rectum.The pathological changes and clinical symptoms of NETs are not specific,and therefore they are frequently misdiagnosed.AIM To investigate the clinical symptoms,pathological characteristics,treatment,and prognosis of rectal neuroendocrine tumors(RNETs)by analyzing the clinical and pathological data of 132 RNET cases at our hospital.METHODS All RNETs were graded according to Ki-67 positivity and mitotic events.The tumors were staged as clinical stages I,II,III,and IV according to infiltrative depth and tumor size.COX proportional hazard model was used to assess the main risk factors for survival.RESULTS These 132 RNETs included 83 cases of G1,21 cases of G2,and 28 cases of G3(neuroendocrine carcinoma)disease.Immunohistochemical staining showed that 89.4%of RNETs were positive for synaptophysin and 39.4%positive for chromogranin A.There were 19,85,23,and 5 cases of clinical stages I,II,III,and IV,respectively.The median patient age was 52.96 years.The diameter of tumor,depth of invasion,and pathological grade were the main reference factors for the treatment of RNETs.The survival rates at 6,12,36,and 60 mo after operation were 98.5%,94.6%,90.2%,and 85.6%,respectively.Gender,tumor size,tumor grade,lymph node or distant organ metastasis,and radical resection were the main factors associated with prognosis of RNETs.Multivariate analysis showed that tumor size and grade were independent prognostic factors.CONCLUSION The clinical symptoms of RNETs are not specific,and they are easy to misdiagnose.Surgery is the main treatment method.The grade and stage of RNETs are the main indices to evaluate prognosis.

Outcomes and prognostic factors of patients with stage? ⅠB and? ⅡA pancreatic cancer according to the 8^(th) edition American Joint Committee on Cancer criteria

AIM To evaluate the changes in the 8^(th) edition American Joint Committee on Cancer(AJCC) for defining stage?ⅠB and?ⅡA pancreatic cancer and identify their prognostic factors.METHODS Pancreatic cancer patients were selected from the Surveillance Epidemiology and End Results database(1973-2013). The enrolled patients were divided into?ⅠB and?ⅡA groups based on tumor size according to the 8^(th) edition AJCC criteria. Clinical characteristics, including age, gender, race, tumor size, primary site, and grade were summarized. Univariate and multivariate analyses were performed to explore the prognostic factors of the?ⅠB and?ⅡA stages of pancreatic cancer under new criteria.RESULTS A total of 1349 pancreatic cancer patients were included. More patients had stage?ⅠB rather than stage?ⅡA. Stage?ⅠB tumors(54.85%) were mainly located in the head of the pancreas, while stage?ⅡA tumors were more often located in the tail and head of the pancreas(35.21% and 31.75%, respectively). The survival time of stage?ⅠB and?ⅡA patients had no significant difference. Univariate and multivariate analyses indicated that the prognostic factors of survival for stage?ⅠB and?ⅡA patients were different. for stage?ⅠB patients, age and primary site were the independent prognostic factors; for stage?ⅡA patients, age and grade were the independent prognostic factors. The risk of death was lower among patients aged ≤ 65 years than those aged > 65 years.CONCLUSION The prognostic factors for stage?ⅠB and?ⅡA patients are different, but age is the independent prognostic factor for all patients. The survival time of stage?ⅠB and?ⅡA patients has no significant difference.

Identification of predictive factors for post-transarterial chemoembolization liver failure in hepatocellular carcinoma patients: A retrospective study

BACKGROUND Post-transarterial chemoembolization(TACE)liver failure occurs frequently in hepatocellular carcinoma(HCC)patients.The identification of predictors for post-TACE liver failure is of great importance for clinical decision-making in this population.AIM To investigate the occurrence rate and predictive factors of post-TACE liver failure in this retrospective study to provide clues for decision-making regarding TACE procedures in HCC patients.METHODS The clinical records of HCC patients treated with TACE therapy were reviewed.Baseline clinical characteristics and laboratory parameters of these patients were extracted.Logistic models were used to identify candidates to predict post-TACE liver failure.RESULTS A total of 199 HCC patients were enrolled in this study,and 70 patients(35.2%)developed post-TACE liver failure.Univariate and multivariate logistic models indicated that microspheres plus gelatin embolization and main tumor size>5 cm were risk predictors for post-TACE liver failure[odds ratio(OR):4.4,95%confidence interval(CI):1.2-16.3,P=0.027;OR:2.3,95%CI:1.05-5.3,P=0.039,respectively].Conversely,HCC patients who underwent tumor resection surgery before the TACE procedure had a lower risk for post-TACE liver failure(OR:0.4,95%CI:0.2-0.95,P=0.039).CONCLUSION Microspheres plus gelatin embolization and main tumor size might be risk factors for post-TACE liver failure in HCC patients,while prior tumor resection could be a favorable factor reducing the risk of post-TACE liver failure.

Investigation of the factors influencing surgical treatment of duodenal gastrointestinal stromal tumors

BACKGROUND Duodenal gastrointestinal stromal tumor(DGIST)is a rare tumor with a specific anatomic site and biological characteristics.As the incidence of lymph node metastasis is very low,the main treatment method is surgery.Two main surgical techniques(local resection and Whipple)are performed in patients with DGISTs.The critical question is which surgical technique to choose.AIM To identify factors influencing the choice of surgery for DGISTs.METHODS The clinicopathological data of patients with DGISTs who underwent surgery between January 1999 and January 2021 were analyzed.We used the Student’s ttest or Mann-Whitney U-test and theχ2 test or Fisher’s exact test to determine the differences between the two groups of patients.Furthermore,we used logistic analysis to identify the relevant factors and independent factors related to the type of surgery.The Kaplan-Meier method was used to analyze the patient’s survival information and Cox regression analysis was performed to determine prognostic risk factors.RESULTS Overall,86 patients were analyzed,including 43 men(50%)and 43 women(50%).We divided the patients into two groups based on surgical technique(local resection or Whipple surgery).There were no differences in the age,mitotic figures,and complications between the two groups;however,the tumor size,tumor location,risk grade,postoperative hospital stay,and abdominal drainage time were significantly different.Based on univariate logistic analysis,the Whipple procedure was chosen if the tumor size was≥5.0 cm,the tumor was located in the descending part of the duodenum,or the risk grade was medium or high.In our research,the five-year overall survival rate of patients was more than 90%.We also describe two DGIST patients with liver metastases at first diagnosis and analyzed their management in order to provide advice on complicated cases.CONCLUSION The Whipple procedure was performed if the primary tumor was in the descending part of the duodenum,tumor size was≥5.0 cm,or the tumor risk grade was medium or high.

Risk factors for lymph node metastasis in patients with pancreatic neuroendocrine neoplasms

BACKGROUND Although PNENs generally have a better prognosis than pancreatic cancers,some PNENs display malignant behavior including lymph node(LN)metastasis.Complete tumor resection can be the only potentially curative treatment for patients with resectable PNENs.However,the indications for LN dissection are still controversial.Over the last decade,minimally invasive surgery such as laparoscopic pancreatic surgery(LPS)has been increasingly performed for pancreatic tumors including PNENs.AIM To investigate the risk factors for LN metastasis in PNENs and to select appropriate patients for limited surgery by LPS.METHODS From April 2001 to December 2019,92 patients underwent pancreatic resection for PNENs at Kumamoto University Hospital.Finally,82 patients were enrolled in this study.Using perioperative factors,we examined the predictive factors for LN metastasis in PNENs.RESULTS Among the 82 patients,the percentage of LN metastasis according to the pathological findings was 12%(10/82 cases).The median tumor size was 12 mm(range:5-90 mm).The median tumor size in the LN-positive group(37 mm)was significantly larger than that in the LN-negative group(12 mm)(P=0.0001).Multivariate analyses revealed that larger tumor size(≥20 mm)was an independent risk factor for LN metastasis(odds ratio 16.8,P=0.0062).In patients with small tumors(≤10 mm),LN metastasis was not found.CONCLUSION Larger tumor size(≥20 mm)is an independent risk factor for LN metastasis in PNENs.In smaller PNENs(≤10 mm),we may be able to choose limited surgery without LN dissection.

Impact of age and tumor size on the development of the Kasabach-Merritt phenomenon in patients with kaposiform hemangioendothelioma:a retrospective cohort study

Introduction The Kasabach–Merritt phenomenon(KMP)is a severe complication of kaposiform hemangioendothelioma(KHE).The risk factors for KMP need further investigation.Methods The medical records of patients with KHE were reviewed.Univariate and multivariate logistic regression models were used for the risk factors for KMP,and the area under the receiver operator characteristic(ROC)curve was used to assess the predictive power of risk factors.Results A total of 338 patients with KHE were enrolled.The incidence of KMP was 45.9%.Age of onset(P<0.001,odds ratio[OR]0.939;95%confidence interval[CI]0.914–0.966),lesion size(P<0.001,OR 1.944;95%CI 1.646–2.296),mixed type(P=0.030,OR 2.428;95%CI 1.092–5.397),deep type(P=0.010,OR 4.006;95%CI 1.389–11.556),and mediastinal or retroperitoneal lesion location(P=0.019,OR 11.864;95%CI 1.497–94.003)were correlated with KMP occurrence through multivariate logistic regression.ROC curve analysis revealed that the optimal cutoffs were 4.75 months for the age of onset(P<0.001,OR 7.206,95%CI 4.073–12.749)and a lesion diameter of 5.35 cm(P<0.001,OR 11.817,95%CI 7.084–19.714).Bounded by a lesion size of 5.35 cm,we found significant differences in tumor morphology,age of onset,treatments,and hematological parameters.Using an onset age of 4.75 months as a cutoff,we found significant differences in tumor morphology,lesion size,hematological parameters,and prognosis.Conclusion For KHE patients with an onset age<4.75 months and/or lesion diameter>5.35 cm,clinicians should be wary of the occurrence of KMP.Active management is recommended to improve the prognosis.

Influence of clinical characteristics and tumor size on symptoms of bladder leiomyoma： a pooled analysis of 61 cases

Background Bladder leiomyoma is an uncommon type of bladder neoplasms. Most publications are reports of isolated cases. The influence of tumor size on patients＇ early symptoms was seldom analyzed. We aim to investigate the clinical characteristics of bladder leiomyoma and the influence of tumor size on patients＇ symptoms in Chinese population. Methods We reviewed the medical records of eight patients diagnosed with bladder leiomyoma at our department, collected 53 cases from Chinese National Knowledge Infrastructure （CNKI）, Wangfang data base, and Chinese Biological Medicine Disk, and performed a pooled analysis. The clinical characteristics of the patients were analyzed and then classified into symptomatic and asymptomatic groups. The association between tumor size and the occurrence of symptoms was evaluated. Furthermore, Logistic regression model was constructed to discriminate variables. Results Women comprised the majority of the patients （49/61, 80.3%）. The mean age and tumor size were （42.3＋14.0） years and （45.0＋25.7） mm, respectively. Among all the symptoms, irritative symptoms occurred most frequently （37.7%, 23/61）, followed by obstructive urinary symptoms （31.1%, 19/61）, hematuria （24.6%, 15/61 ）, and abdominal bulge or pain （14.8%, 9/61）. In our study, patients who were 45 years old or younger tended to be asymptomatic compared with elder ones （14/36 vs. 3/25, P=-0.021）. The histological, as well as anatomical, location of tumor, did not show significant differences between symptomatic and asymptomatic patients （P=-0.306 and 0.700）. Tumors larger than 30 mm in the greatest diameter would cause clinical symptoms such as obstructive urinary symptoms （P=0.048） and irritative symptoms （P=0.037）. Logistic regression confirmed the association between tumor size and the occurrence of symptoms, which was related with age. Conclusions Bladder leiomyoma occurs mainly in women and most frequently with irritative symptoms. The occurrence of symptoms is related to tumor size rather than the location： In this setting, patients with endovesical tumors smaller than 30 mm in the greatest diameter tended to be asymptomatic, which were usually treated with transurethrai resection of bladder tumor.

Predictive factors for the success of “one-off” ablation in single hepatocellular carcinoma patients who underwent percutaneous radiofrequency ablation

Aim:To investigate the technique’s effectiveness and evaluate the risk factors affecting the success of“one-off”percutaneous ultrasound-guided radiofrequency ablation(RFA)for single hepatocellular carcinoma(HCC).Methods:A total of 462 consecutive patients who received RFA from February 2010 to December 2013 at a single center(Eastern Hepatobiliary Surgery Hospital,Shanghai,China)were enrolled in the study.The patients were followed up for at least 6 months.Herein,this study adopted a new terminology named“one-off”ablation which is defined as achieving complete necrosis and no local residual or recurrent tumor within 6 months after single-session RFA.The incidence of“one-off”RFA was observed and the attributing risk factors were analyzed.A multivariate analysis was conducted to determine the independent predictive factors for the success of“one-off”ablation.Results:The technique’s effectiveness was 90.0%(416/462).After 6 months,281 patients achieved“one-off”ablation,while 181 patients failed.On univariate analysis,tumor size≤3 cm and tumor further from organs were found to be significantly correlated with“one-off”complete ablation(P=0.003,and P=0.010,respectively).On multivariate analysis using a logistic regression,tumor size≤3 cm[odds ratio(OR),0.534;95%confidence interval(CI):0.346-0.825,P=0.005]and tumor further from organs(OR,0.593;95%CI:0.387-0.909,P=0.017)remained predictive.Conclusion:Tumor size and tumor location are the predictive factors for the success of“one-off”ablation in patients with single HCC.