Resection Strategies Research Articles

Clinical usefulness of hybrid endoscopic submucosal dissection for T1b colorectal carcinomas ≤20 mm to ensure adequate vertical margins.

To evaluate endoscopic resection strategies for cT1b colorectal carcinomas (CRCs) ≤20 mm to determine strategies that enable adequate vertical margins (VMs). We enrolled 128 consecutive patients with cT1b colorectal carcinomas ≤20 mm resected by endoscopic mucosal resection or hybrid endoscopic submucosal dissection (ESD). Tumor lifting conditions after submucosal injection were classified into type A (lifting, soft dome-like), type B (lifting, hard trapezoid-like), and non-lifting (positive non-lifting sign). Predictors of positive VMs (VM 1) and adequate VMs were identified. All non-lifting tumors were resected by hybrid ESD and VMs were ≥500 µm. Vertical margin 1 tumors were only found in the endoscopic mucosal resectiongroup, in which, the proportion of type B tumors with VM 1 was significantly higher than that of tumors with negative VMs (p<0.01). Type A tumors showed no significant between-group differences. Among type B tumors, the proportion of VMs ≥500 µm was significantly higher (p<0.01) and the VM distance was significantly longer (p<0.01) in the hybrid ESD group than in the endoscopic mucosal resection group. Hybrid ESD can be selected for type B tumors to ensure adequate VMs.

Development and external validation of a nomogram for predicting lymph node metastasis in 1-3cm lung adenocarcinoma.

Aim: This study aimed to investigate the risk factors for lymph node metastasis in 1-3cm adenocarcinoma and develop a new nomogram to predict the probability of lymph node metastasis.Materials & methods: This study collected clinical data from 1656 patients for risk factor analysis and an additional 500 patients for external validation. The logistic regression analyses were employed for risk factor analysis. The least absolute shrinkage and selection operator regression was used to select variables, and important variables were used to construct the nomogram and an online calculator.Results: The nomogram for predicting lymph node metastasis comprises six variables: tumor size (mediastinal window), consolidation tumor ratio, tumor location, lymphadenopathy, preoperative serum carcinoembryonic antigen level and pathological grade. According to the predicted results, the risk of lymph node metastasis was divided into low-risk group and high-risk group. We confirmed the exceptional clinical efficacy of the model through multiple evaluation methods.Conclusion: The importance of intraoperative frozen section is increasing. We discussed the risk factors for lymph node metastasis and developed a nomogram to predict the probability of lymph node metastasis in 1-3cm adenocarcinomas, which can guide lymph node resection strategies during surgery.

A multi-docking strategy for robotic LAR and deep pelvic surgery with the Hugo RAS system: experience from a tertiary referral center.

In June 2023, our institution adopted the Medtronic Hugo RAS system for colorectal procedures. This system's independent robotic arms enable personalized docking configurations. This study presents our refined multi-docking strategy for robotic low anterior resection (LAR) and deep pelvic procedures, designed to maximize the Hugo RAS system's potential in rectal surgery, and evaluates the associated learning curve. This retrospective analysis included 31 robotic LAR procedures performed with the Hugo RAS system using our novel multi-docking strategy. Docking times were the primary outcome. The Mann-Kendall test, Spearman's correlation, and cumulative sum (CUSUM) analysis were used to assess the learning curve and efficiency gains associated with the strategy. Docking times showed a significant negative trend (p < 0.01), indicating improved efficiency with experience. CUSUM analysis confirmed a distinct learning curve, with proficiency achieved around the 15th procedure. The median docking time was 6min, comparable to other robotic platforms after proficiency. This study demonstrates the feasibility and effectiveness of a multi-docking strategy in robotic LAR using the Hugo RAS system. Our personalized approach, capitalizing on the system's unique features, resulted in efficient docking times and streamlined surgical workflow. This approach may be particularly beneficial for surgeons transitioning from laparoscopic to robotic surgery, facilitating a smoother adoption of the new technology. Further research is needed to validate the generalizability of these findings across different surgical settings and experience levels.

P4.07F.02 Invasiveness Diagnosis by Intraoperative Frozen Section Guides Resection Strategy Amomg ≤2cm Non-Small-Cell Lung Cancer

P4.07F.02 Invasiveness Diagnosis by Intraoperative Frozen Section Guides Resection Strategy Amomg ≤2cm Non-Small-Cell Lung Cancer

Effect of powered circular stapler in colorectal anastomosis after left-sided colic resection: systematic review and meta-analysis

PurposeAnastomotic leak (AL) remains the most important complication after left-sided colic anastomoses and technical complications during anastomotic construction are responsible of higher leakage incidence. Powered circular stapler (PCS) in colorectal surgery has been introduced in order to reduce technical errors and post-operative complications due to the manual circular stapler (MCS).MethodsA systematic review and meta-analysis were performed. An electronic systematic search was performed using Web of Science, PubMed, and Embase of studies comparing PCS and MCS. The incidence of AL, anastomotic bleeding (AB), conversion, and reoperation were assessed. PROSPERO Registration Number: CRD42024512644.ResultsFive observational studies were eligible for inclusion reporting on 2379 patients. The estimated pooled Risk Ratios for AL and AB rates following PCS were significantly lower than those observed with MCS (0.44 and 0.23, respectively; both with p < 0.01). Conversion and reoperation rate did not show any significant difference: 0.41 (95% CI 0.09–1.88; p = 0.25) and 0.78 (95% CI 0.33–1.84; p = 0.57); respectively.ConclusionThe use of PCS demonstrates a lower incidence of AL and AB compared to MCS but does not exhibit a discernible influence on reintervention or conversion rates. The call for future randomized clinical trials aims to definitively clarify these issues and contribute to further advancements in refining surgical strategies for left-sided colonic resection.

Optimization of endoscopic treatment strategies for R0 resection of rectal neuroendocrine tumors smaller than 10 mm

BackgroundThe optimal histologically complete (R0) resection methods of endoscopy for rectal neuroendocrine tumor (NET) ≤ 10 mm remains controversial. We aimed to assess the optimal endoscopic treatments for NETs. MethodsThe retrospective enrolled patients (n = 208) with rectal NETs were divided into 3 subsets according to pathological tumor size: 2 - 3 mm, 4 - 5 mm, and 6 - 10 mm NETs. Factors associated with R0 resection according to different endoscopic treatments (accidental diagnostic biopsy by cold forceps, endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD)) and tumor size were investigated. All patients underwent follow-up and no local recurrence or metastasis were identified. ResultsA total of 208 patients were enrolled. In patients with 2 - 3 mm NETs, the R0 resection rate was 100.0 % for biopsy, EMR, and ESD. The R0 resection rate for biopsy of 4 - 5 mm and 6 - 10 mm NETs was 34.3 % and 0.0 % respectively, which was inferior to the EMR/ESD rate (4 - 5mm: p < 0.001; 6 - 10 mm: p < 0.001: respectively). For patients with ≤ 10 mm NETs, EMR and ESD had a comparable en bloc (p = 0.082) and R0 resection rates (p = 0.651). ConclusionAccidental diagnostic biopsy by cold forceps could be considered as the possible treatment for 2 - 3 mm rectal NETs. And for patients with ≤ 10 mm rectal NETs, both EMR and ESD might be sufficient.

Seizure outcome in surgically treated pediatric gangliogliomas and dysembryoplastic neuroepitheliomas according to imaging and resection strategies

PurposeImaging and resection strategies for pediatric gangliogliomas (GG) and dysembryoplastic neuroepitheliomas (DNET) presenting with epilepsy were retrospectively analyzed in a consecutive institutional series of surgically treated patients. MethodsTwenty-two children (median 8 years, 3–18 years) presented with seizures for 30 months median (14–55.2 months) due to a histologically verified GG/DNET. ResultsThere were 20 GG and 2 DNT, 68 % located temporal, 32 % extra-temporal. Seizure history was significantly longer in temporal cases (38 versus 14 months median, p < 0.01). MRI contrast enhancement was present in 50 % and methionine (MET) positron emission tomography (PET) uptake in 70 % (standard uptake values (SUVs) 2.92 mean, from 1.6 to 6.4). 27 % had glucose PET hypometabolism. Primarily, in temporal GG, ECoG (electrocorticography) -guided lesionectomies were performed in 87 % and antero-mesial temporal lobe resections (AMTLR) in 13 %, whereas in extra-temporal GG/DNETs, lesionectomies were performed in 100 %. ILAE Class 1 seizure outcome was primarily achieved in 73 % of the temporal cases, and was increased to 93 % by performing six repeat surgeries using AMTLR. Extratemporal patients experienced ILAE Class 1 seizure outcomes in 86 % without additional surgeries, although harboring significantly more residual tumor (p < 0.005, mean follow-up 28 months). ConclusionIn children, MET PET imaging for suspected GG is proposed preoperatively showing a high diagnostic sensitivity and an option to delineate the lesions for navigated resection, whereas MRI contrast behavior was of no differential diagnostic use. As a surgical strategy we propose primarily lesionectomies for extratemporal but AMTLR for temporal GG respecting eloquent brain areas.

Risk Factors for Recurrence of Crohn's Disease After Ileocecal Resection and Management Strategies

IntroductionPediatric patients with ileocecal Crohn's Disease (CD) refractory to medical management frequently require ileocecectomy. However, risk factors for post-operative ileocecal recurrence and appropriate management strategies are poorly defined in the pediatric literature in the biologic era. MethodsWe queried our institutional database from 1/1/2012–12/31/2022 for patients aged 1–21 who underwent primary ileocecectomy for CD. We analyzed baseline characteristics, operative details, medical management, recurrence patterns, and management patterns. ResultsWe identified 208 patients who underwent primary ileocecal resection, of which 66 (23%) demonstrated endoscopic recurrence at 2.1 ± 0.5 years and 28 (13%) developed clinical recurrence at 2.5 ± 0.8 years. Recurrence was at the surgical anastomosis in 43 (21%). Before surgery, 138 (66%) were treated with a biologic, of which 25 (18%) were transitioned to a second line biologic pre-operatively. Requiring a separate intervention for perianal or intestinal disease increased the odds of recurrence on multivariable analysis, as did requiring a second line biologic. Of those with endoscopic recurrence, most [62/66 (94%)] were successfully managed with medical optimization alone. Only four (6.7%) required procedural intervention with two being managed with endoscopic balloon dilation and two requiring repeat resection and re-anastomosis. Median follow up was 2.6 years [IQR 1.2–4.5]. ConclusionRequiring separate interventions for perianal or intestinal disease and demonstrating disease difficult to medically control may increase the risk of recurrent post-operative ileocecal CD. Such patients should be closely surveilled for endoscopic recurrence and may warrant more aggressive medical regimens. Recurrence can typically be managed medically with few patients requiring procedural intervention. Level of EvidenceIII.

Management of functional neuroendocrine tumors

Functional neuroendocrine neoplasms (NENs) are those associated with specific symptoms related to the hormonal secretion of the NENs. Although less than 25 % of NENs are functional at diagnosis,1 the associated syndromes significantly increase the patient burden of disease. Management of hormonal NEN symptoms may involve tumor resection or other reduction strategies (e.g., chemotherapy, embolotherapy, etc), but also specific therapies directed at decreasing hormonal synthesis, secretion, or end-organ effects. In this review, we focus on specific symptomatic management of many of the NEN syndromes, which may be pursued in addition to management primarily directed at tumor bulk and growth. A continued focus on symptom management related to the hormonal secretions of NENs, in the context of other efforts to reduce tumor bulk and growth, could significantly improve patient wellbeing.

Laparoscopic right upper transversal hepatectomy: Strategies for right hepatic vein resection and reconstruction

ObjectiveThe right upper transversal hepatectomy (RUTH) is considered a complex technique of parenchymal-sparing hepatectomies. The intraoperative management of the right hepatic vein (RHV) is still controversial because it may cause obstruction of outflow in the remnant hepatic segment. The aim of this study is to present our experience of laparoscopic RUTH and the strategy of RHV resection and reconstruction in different settings. MethodsFive patients who underwent laparoscopic RUTH for liver tumor were enrolled retrospectively. Clinical and pathological features of the patients, peri-operative treatment, as well as short- and long-term outcomes were collected for analysis. ResultsLaparoscopic RUTH was successfully performed in all five patients. Two individuals underwent RUTH while preserving RHV. Among the remaining patients who underwent RUTH with RHV resection, one patient underwent RHV reconstruction but the others did not. Immediate or long-term venous related complications did not occurred in a median follow-up period of nine months. ConclusionsLaparoscopic RUTH surgery for tumors in the right upper region of the liver is safe and feasible. The strategic workflow we proposed for the resection and reconstruction of the RHV offers a reliable method for preserving liver parenchyma and reducing the risk of postoperative liver failure.

Unveiling hierarchy and spatial distribution of O6-methylguanine-DNA methyltransferase promoter methylation in World Health Organization grade 2-3 gliomas.

This study investigated the role of O6-methylguanine-DNA methyltransferase promoter (MGMTp) methylation hierarchy and heterogeneity in grade 2-3 gliomas, focusing on variations in chemotherapy benefits and resection dependency. A cohort of 668 newly diagnosed grade 2-3 gliomas, with comprehensive clinical, radiological, and molecular data, formed the basis of this analysis. The extent of resection was categorized into gross total resection (GTR ≥100%), subtotal resection (STR >90%), and partial resection (PR ≤90%). MGMTp methylation levels were examined using quantitative pyrosequencing. Our findings highlighted the critical role of GTR in improving the prognosis for astrocytomas (IDH1/2-mutant and 1p/19q non-codeleted), contrasting with its lesser significance for oligodendrogliomas (IDH1/2 mutation and 1p/19q codeletion). Oligodendrogliomas demonstrated the highest average MGMTp methylation levels (median: 28%), with a predominant percentage of methylated cases (average methylation levels >20%). Astrocytomas were more common in the low-methylated group (10%-20%), while IDH wild-type gliomas were mostly unmethylated (<10%). Spatial distribution analysis revealed a decrement in frontal lobe involvement from methylated, low-methylated to unmethylated cases (72.8%, 59.3%, and 47.8%, respectively). In contrast, low-methylated and unmethylated cases were more likely to invade the temporal-insular region (19.7%, 34.3%, and 40.4%, respectively). Astrocytomas with intermediate MGMTp methylation were notably associated with temporal-insular involvement, potentially indicating a moderate response to temozolomide and underscoring the importance of aggressive resection strategies. In conclusion, our study elucidates the complex interplay of MGMTp methylation hierarchy and heterogeneity among grade 2-3 gliomas, providing insights into why astrocytomas and IDH wild-type lower-grade glioma might derive less benefit from chemotherapy.

Differences in the Prognostic Role of Age, Extent of Resection, and Tumor Grade between Astrocytoma IDHmt and Oligodendroglioma: A Single-Center Cohort Study.

IDH-mutant glioma is classified as oligodendroglioma or astrocytoma based on 1p19q-codeletion. Whether prognostic factors are similar between these tumor types is not well understood. Retrospective cohort study. Molecular characterization was performed with targeted next-generation sequencing. Tumor volumes were calculated using semiautomatic 3D segmentation on all pre- and post-operative MRI scans. Overall survival was assessed with the Cox-proportional hazards model. A total of 383 patients with newly diagnosed IDH-mutant glioma were followed up for a median of 7.2 years. Grades 3 and 4 patients had significantly lower Karnofsky performance, with tumors having more contrast enhancement. Patients also received more aggressive postsurgery treatment. Postoperative tumor volume is significantly and independently associated with survival (HR, per cm3 1.19; 95% CI, 1.03-1.39) in IDH-mutant glioma. A separate analysis of oligodendroglioma and astrocytoma showed a significant association of postoperative tumor volume in astrocytoma but not in oligodendroglioma. Higher age and histologic tumor grade were associated with worse survival in patients with oligodendroglioma but not with astrocytoma. Our data support an initial strategy of extensive resection in patients with oligodendroglioma and astrocytoma. Other important prognostic factors differ between these tumor types, urging researchers and clinicians to keep treating these tumors as separate entities.

Individualized epidemic spreading models predict epilepsy surgery outcomes: A pseudo-prospective study.

Epilepsy surgery is the treatment of choice for drug-resistant epilepsy patients, but up to 50% of patients continue to have seizures one year after the resection. In order to aid presurgical planning and predict postsurgical outcome on a patient-by-patient basis, we developed a framework of individualized computational models that combines epidemic spreading with patient-specific connectivity and epileptogeneity maps: the Epidemic Spreading Seizure and Epilepsy Surgery framework (ESSES). ESSES parameters were fitted in a retrospective study (N = 15) to reproduce invasive electroencephalography (iEEG)-recorded seizures. ESSES reproduced the iEEG-recorded seizures, and significantly better so for patients with good (seizure-free, SF) than bad (nonseizure-free, NSF) outcome. We illustrate here the clinical applicability of ESSES with a pseudo-prospective study (N = 34) with a blind setting (to the resection strategy and surgical outcome) that emulated presurgical conditions. By setting the model parameters in the retrospective study, ESSES could be applied also to patients without iEEG data. ESSES could predict the chances of good outcome after any resection by finding patient-specific model-based optimal resection strategies, which we found to be smaller for SF than NSF patients, suggesting an intrinsic difference in the network organization or presurgical evaluation results of NSF patients. The actual surgical plan overlapped more with the model-based optimal resection, and had a larger effect in decreasing modeled seizure propagation, for SF patients than for NSF patients. Overall, ESSES could correctly predict 75% of NSF and 80.8% of SF cases pseudo-prospectively. Our results show that individualised computational models may inform surgical planning by suggesting alternative resections and providing information on the likelihood of a good outcome after a proposed resection. This is the first time that such a model is validated with a fully independent cohort and without the need for iEEG recordings.

Short-term outcomes of robotic left ventricular patch ventriculoplasty for significant mitral annular calcification

ObjectiveSurgical management of mitral annular calcification remains challenging. Our institution pursued a strategy of total mitral annular calcification resection with pericardial patch reconstruction of the left ventricle when primary atrioventricular groove closure was not possible. We present the short-term outcomes derived after implementing this strategy. MethodsA single-institution retrospective analysis included patients with significant mitral annular calcification undergoing totally endoscopic robotic mitral valve surgery between October 2009 and August 2023. Mitral valve repair was performed in patients with sufficient posterior leaflet length. Patients requiring pericardial patch ventriculoplasty were compared with those in whom primary atrioventricular groove closure was possible (non–pericardial patch ventriculoplasty). ResultsOf 1441 patients who underwent totally endoscopic mitral valve surgery, 217 (15.1%) presented with significant mitral annular calcification. Pericardial patch ventriculoplasty was performed in 69 patients (31.8%). Patients undergoing non–pericardial patch ventriculoplasty were significantly younger than patients undergoing pericardial patch ventriculoplasty (63.4 vs 67.8 years, P = .01). Mitral valve repair was conducted in 145 patients (98.0%) in the non–pericardial patch ventriculoplasty group versus 56 patients (81.2%) in the pericardial patch ventriculoplasty group (P < .01). The median postoperative length of stay was significantly shorter in the non–pericardial patch ventriculoplasty group (3 vs 5 days, P < .01). There was no significant difference in postoperative stroke (0.7% vs 2.9%, P = .50) or 30-day mortality (1.4% vs 1.4%, P = 1.00). Three-year survival was comparable between the groups (97.4% vs 93.7%, P = .52). ConclusionsTotally endoscopic robotic mitral valve repair is a safe and feasible technique for the management of mitral annular calcification with promising results at 3 years. Patients who required atrioventricular groove pericardial patch reconstruction had similar outcomes to those in whom primary closure was possible.

3D-SARC: A Pilot Study Testing the Use of a 3D Augmented-Reality Model with Conventional Imaging as a Preoperative Assessment Tool for Surgical Resection of Retroperitoneal Sarcoma.

Retroperitoneal sarcomas (RPSs) present a surgical challenge, with complex anatomic relationships to organs and vascular structures. This pilot study investigated the role of three-dimensional (3D) augmented reality (3DAR) compared with standard imaging in preoperative planning and resection strategies. For the study, 13 patients who underwent surgical resection of their RPS were selected based on the location of their tumor (right, left, pelvis). From the patients' preoperative computed tomography (CT) scans, 3DAR models were created using a D2P program and projected by an augmented-reality (AR) glass (Hololens). The 3DAR models were evaluated by three experienced sarcoma surgeons and compared with the baseline two-dimensional (2D) contrast-enhanced CT scans. Three members of the surgical team evaluated 13 models of retroperitoneal sarcomas, resulting in a total of 26 responses. When the surgical team was asked to evaluate whether the 3DAR better prepared the surgeon for planned surgical resection, 10 responses favored the 3DAR, 5 favored the 2D CT scans and 11 showed no difference (p = 0.074). According to 15 (57.6 %) of the 26 responses, the 3DAR offered additional value over standard imaging in the preoperative planning (median score of 4; range, 1-5). The median stated likelihood that the surgeons would consult the 3DAR was 5 (range, 2-5) for the preoperative setting and 3 (range, 1-5) for the intraoperative setting. This pilot study suggests that the use of 3DAR may provide additional value over current standard imaging in the preoperative planning for surgical resection of RPS, and the technology merits further study.

Endocrine oncology : An update on surgical treatments

In the management of solid tumours, routine concepts are increasingly being transformed into individualized patient treatment. Endocrine surgery is traditionally characterized by resection strategies that are adapted to phenotype and genotype of the underlying disease. As complication rates in surgery correlate with the extent of resection, continuous efforts are made to identify selection criteria in order to limit the extent of surgery without compromising the oncological outcome. The aim is to design risk-stratified precision endocrine surgery. Asearch was carried out in PubMed for new and modern strategies and approaches for oncological endocrine surgery. Several developments in surgical technique and technology, molecular pathology, medical therapy, and study data identify the potential to adapt the surgical strategy in all areas of endocrine surgery. According to prevalent data, limited extent of resection in thyroid cancer surgery shows a reduction in complication rates while preserving oncological outcome when adequate selection criteria are implemented. New insights and innovative technologies also influence additional areas in oncological endocrine surgery for parathyroid, adrenal, and neuroendocrine neoplasia. However, the broad practice of these new concepts needs to be evaluated with regard to long-term oncological outcome.

Long-term outcomes of endoscopic submucosal dissection for undifferentiated type early gastric cancer over 2 cm with R0 resection.

Endoscopic submucosal dissection (ESD) for over 2 cm in size undifferentiated type (UD type) early gastric cancer (EGC) confined to the mucosa is not only challenging, but also long-term outcomes are not well known. To evaluate the long-term outcomes of ESD done for UD type EGCs confined to the mucosa over 2 cm in size and compare the results with those where the lesions were less than 2 cm. 143 patients with UD type EGC confirmed on histology after ESD at a tertiary hospital were reviewed. Cases with synchronous and metachronous lesions and a case with emergency surgery after ESD were excluded. A total of 137 cases were enrolled. 79 cases who underwent R0 resection were divided into 2 cm or less (group A) and over 2 cm (group B) in size. Among 79 patients who underwent R0 resection, the number in group A and B were 51 and 28, respectively. The mean follow-up period (SD) was 79.71 ± 45.42 months. There was a local recurrence in group A (1/51, 2%) and group B (1/28, 3.6%) respectively. This patient in group A underwent surgery while the patient in group B underwent repeated ESD with no further recurrences in both patients. There was no regional lymph node metastasis, distant metastasis, and deaths in both groups. With R0 resection strategy for ESD on lesions over 2 cm, 20.4% (28/137) of patients were able to avoid surgery compared with expanded indication. If R0 resection is achieved by ESD, UD type EGCs over 2 cm also showed good and similar clinical outcomes as compared to lesions less than 2 cm when followed for over 5 years. With R0 resection strategy, several patients can avoid surgery.

Navigating Complex Challenges: Preoperative Assessment and Surgical Strategies for Liver Resection in Patients with Fibrosis or Cirrhosis.

This review explores the intricacies of evaluating cirrhotic patients for liver resection while exploring how to extend surgical intervention to those typically excluded by the Barcelona Clinic Liver Cancer (BCLC) criteria guidelines by focusing on the need for robust preoperative assessment and innovative surgical strategies. Cirrhosis presents unique challenges and complicates liver resection due to the altered physiology of the liver, portal hypertension, and liver decompensation. The primary objective of this review is to discuss the current approaches in assessing the suitability of cirrhotic patients for liver resection and aims to identify which patients outside of the BCLC criteria can safely undergo liver resection by highlighting emerging strategies that can improve surgical safety and outcomes.

Outcomes in colorectal endoscopic submucosal dissection for large protruded lesions: A retrospective multicenter study

Abstract Background and study aims Colorectal endoscopic submucosal dissection (ESD) is increasingly used for treating early-stage colorectal cancer, including large, protruded lesions (LPL). However, the challenges posed by LPLs, especially those accompanied by severe fibrosis or muscle-retracting sign (MRS), remain unclear. This study aims to investigate ESD outcomes for LPL, focusing on factors such as tumor size and, submucosal fibrosis. Patients and methods In a multicenter retrospective study (June 2012 to May 2023), data from 526 patients with 542 LPL lesions (≥ 2 cm) were analyzed. Parameters included lesion size, procedure time, dissection speed, physician experience, submucosal fibrosis, and adverse events. The tunnel method, including the double tunnel method, was used for cases with severe fibrosis or MRS. Multivariate analysis assessed factors affecting procedure difficulty, particularly LPLs ≥ 4 cm. Results The study revealed an impressive en bloc resection rate of 97.8% and a curative resection rate of 78.6% for LPLs. Notably, fibrosis and MRS were present in 25% and 18% of 4-cm LPLs, respectively, and their frequency tended to increase as the tumor diameter increased. One treatment strategy for LPLs was the tunneling method, which was used most frequently (41 cases, 7.6%). Factors affecting dissection speed included larger tumor size, submucosal fibrosis, MRS, and physician experience. Conclusions Treating LPLs through colorectal ESD presents significant challenges, especially in patients with fibrosis and MRS. This study highlights the importance of recognizing these complexities, and that more reliable resection strategy must be established for accurate pathological evaluation

Comparative evaluation of volumetry estimation from plain and contrast enhanced computed tomography liver images.

Surgery planning for liver tumour is carried out using contrast enhanced computed tomography (CECT) images to determine the optimal resection strategy and to assess the volume of liver and tumour. Current surgery planning tools interpret even the functioning liver cells present within the tumour boundary as tumour. Plain CT images provide inadequate information for treatment planning. This work attempts to address two shortcomings of existing surgery planning tools: (i) to delineate functioning liver cells from the non-functioning tumourous tissues within the tumour boundary and (ii) to provide 3D visualization and actual tumour volume from the plain CT images. All slices of plain CT images containing liver are enhanced by means of fuzzy histogram equalization in Non-Subsampled Contourlet Transform (NSCT) domain prior to 3D reconstruction to clearly delineate liver, non-functioning tumourous tissues and functioning liver cells within the tumour boundary. The 3D analysis from plain and CECT images was carried out on five types of liver lesions viz. HCC, metastasis, hemangioma, cyst, and abscess along with normal liver. The study resulted in clear delineation of functional liver tissues from non-functioning tumourous tissues within the tumour boundary from CECT as well as plain CT images. The volume of liver calculated using the proposed approach is found comparable with that obtained using Myrian-XP, a currently followed surgery planning tool in clinical practice. The obtained results from plain CT images will undoubtedly provide valuable diagnostic assistance and surgery planning even for the subset of patients for whom CECT acquisition is not advisable.