Neoadjuvant Immunotherapy in Locally Advanced Mismatch Repair-Deficient Colon Cancer.

BACKGROUND: Mismatch repair-deficient (dMMR) tumors can be found in 10 to 15% of patients with nonmetastatic colon cancer. In these patients, the efficacy of chemotherapy is limited. The use of neoadjuvant immunotherapy has shown promising results, but data from studies of this approach are limited. METHODS: We conducted a phase 2 study in which patients with nonmetastatic, locally advanced, previously untreated dMMR colon cancer were treated with neoadjuvant nivolumab plus ipilimumab. The two primary end points were safety, defined by timely surgery (i.e., ≤2-week delay of planned surgery owing to treatment-related toxic events), and 3-year disease-free survival. Secondary end points included pathological response and results of genomic analyses. RESULTS: Of 115 enrolled patients, 113 (98%; 97.5% confidence interval [CI], 93 to 100) underwent timely surgery; 2 patients had surgery delayed by more than 2 weeks. Grade 3 or 4 immune-related adverse events occurred in 5 patients (4%), and none of the patients discontinued treatment because of adverse events. Among the 111 patients included in the efficacy analysis, a pathological response was observed in 109 (98%; 95% CI, 94 to 100), including 105 (95%) with a major pathological response (defined as ≤10% residual viable tumor) and 75 (68%) with a pathological complete response (0% residual viable tumor). With a median follow-up of 26 months (range, 9 to 65), no patients have had recurrence of disease. CONCLUSIONS: In patients with locally advanced dMMR colon cancer, neoadjuvant nivolumab plus ipilimumab had an acceptable safety profile and led to a pathological response in a high proportion of patients. (Funded by Bristol Myers Squibb; NICHE-2 ClinicalTrials.gov number, NCT03026140.).

Endoscopic En Bloc Versus Piecemeal Resection of Large Nonpedunculated Colonic Adenomas : A Randomized Comparative Trial.

BACKGROUND: Endoscopic resection of adenomas prevents colorectal cancer, but the optimal technique for larger lesions is controversial. Piecemeal endoscopic mucosal resection (EMR) has a low adverse event (AE) rate but a variable recurrence rate necessitating early follow-up. Endoscopic submucosal dissection (ESD) can reduce recurrence but may increase AEs. OBJECTIVE: To compare ESD and EMR for large colonic adenomas. DESIGN: Participant-masked, parallel-group, superiority, randomized controlled trial. (ClinicalTrials.gov: NCT03962868). SETTING: Multicenter study involving 6 French referral centers from November 2019 to February 2021. PARTICIPANTS: Patients with large (≥25 mm) benign colonic lesions referred for resection. INTERVENTION: The patients were randomly assigned by computer 1:1 (stratification by lesion location and center) to ESD or EMR. MEASUREMENTS: The primary end point was 6-month local recurrence (neoplastic tissue on endoscopic assessment and scar biopsy). The secondary end points were technical failure, en bloc R0 resection, and cumulative AEs. RESULTS: In total, 360 patients were randomly assigned to ESD (n = 178) or EMR (n = 182). In the primary analysis set (n = 318 lesions in 318 patients), recurrence occurred after 1 of 161 ESDs (0.6%) and 8 of 157 EMRs (5.1%) (relative risk, 0.12 [95% CI, 0.01 to 0.96]). No recurrence occurred in R0-resected cases (90%) after ESD. The AEs occurred more often after ESD than EMR (35.6% vs. 24.5%, respectively; relative risk, 1.4 [CI, 1.0 to 2.0]). LIMITATION: Procedures were performed under general anesthesia during hospitalization in accordance with the French health system. CONCLUSION: Compared with EMR, ESD reduces the 6-month recurrence rate, obviating the need for systematic early follow-up colonoscopy at the cost of more AEs. PRIMARY FUNDING SOURCE: French Ministry of Health.

Treatment interval in curative treatment of colon cancer, does it impact (cancer free) survival? A non-inferiority analysis.

BACKGROUND: In treatment of colon cancer, strict waiting-time targets are enforced, leaving professionals no room to lengthen treatment intervals when advisable, for instance to optimise a patient's health status by means of prehabilitation. Good quality studies supporting these targets are lacking. With this study we aim to establish whether a prolonged treatment interval is associated with a clinically relevant deterioration in overall and cancer free survival. METHODS: This retrospective multicenter non-inferiority study includes all consecutive patients who underwent elective oncological resection of a biopsy-proven primary non-metastatic colon carcinoma between 2010 and 2016 in six hospitals in the Southern Netherlands. Treatment interval was defined as time between diagnosis and surgical treatment. Cut-off points for treatment interval were ≤35 days and ≤49 days. FINDINGS: 3376 patients were included. Cancer recurred in 505 patients (15.0%) For cancer free survival, a treatment interval >35 days and >49 days was non-inferior to a treatment interval ≤35 days. Results for overall survival were inconclusive, but no association was found. CONCLUSION: For cancer free survival, a prolonged treatment interval, even over 49 days, is non-inferior to the currently set waiting-time target of ≤35 days. Therefore, the waiting-time targets set as fundamental objective in current treatment guidelines should become directional instead of strict targets.

Change in abdominal obesity after colon cancer surgery - effects of left-sided and right-sided colonic resection.

BACKGROUND: Excess abdominal visceral adipose tissue (VAT) is associated with metabolic diseases and poor survival in colon cancer (CC). We assessed the impact of different types of CC surgery on changes in abdominal fat depots. MATERIAL AND METHODS: Computed tomography (CT)-scans performed preoperative and 3 years after CC surgery were analyzed at L3-level for VAT, subcutaneous adipose tissue (SAT) and total adipose tissue (TAT) areas. We assessed changes in VAT, SAT, TAT and VAT/SAT ratio after 3 years and compared the changes between patients who had undergone left-sided and right-sided colonic resection in the total population and in men and women separately. RESULTS: A total of 134 patients with stage I-III CC undergoing cancer surgery were included. Patients who had undergone left-sided colonic resection had after 3 years follow-up a 5% (95% CI: 2-9%, p < 0.01) increase in abdominal VAT, a 4% (95% CI: 2-6%, p < 0.001) increase in SAT and a 5% increase (95% CI: 2-7%, p < 0.01) in TAT. Patients who had undergone right-sided colonic resection had no change in VAT, but a 6% (95% CI: 4-9%, p < 0.001) increase in SAT and a 4% (95% CI: 1-7%, p < 0.01) increase in TAT after 3 years. Stratified by sex, only males undergoing left-sided colonic resection had a significant VAT increase of 6% (95% CI: 2-10%, p < 0.01) after 3 years. CONCLUSION: After 3 years follow-up survivors of CC accumulated abdominal adipose tissue. Notably, those who underwent left-sided colonic resection had increased VAT and SAT, whereas those who underwent right-sided colonic resection demonstrated solely increased SAT.

Standardization of Colon Resection for Cancer: An Overview of the American College of Surgeons Commission on Cancer Standard 5.6.

The purpose of this editorial is to review the American College of Surgeons Commission on Cancer Standard 5.6, which pertains to curative intent colon resections performed for cancer. We first provide a broad overview of the Operative Standard, followed by the underlying rationale, technical components, and documentation requirements.

Efficacy and Safety Analysis of Emergency Endoscopic Self-Expanding Metal Stent Placement Without Fluoroscopic Assistance for Right-Sided Colonic Cancer Obstruction.

BACKGROUND: Traditionally, surgical treatment is recommended for right-sided colonic cancer obstruction (RCCO); however, the literature comparing surgical or non-surgical procedures is lacking. METHODS: Patients included in this study were divided into two groups: one group received elective surgery after self-expanding metal stent (SEMS) placement, i.e., the bridge to surgery (BTS) group, and one group received emergency surgery (ES). RESULTS: Thirty-five patients were included in the BTS group and 60 patients underwent ES. The technical and clinical success rates for SEMS placement were 100% and 88.6%, respectively, while the short-term complication rates were 51.4% and 33.3% for the BTS and ES groups, respectively (p = 0.082). Overall, 2.9% and 3.3% of postoperative deaths occurred in the BTS and ES groups (p = 1.000). The 1-year overall survival (OS) rates were 91.4% and 88.3% (p = 0.840), 3-year OS rates were 85.7% and 81.7% (p = 0.860), and 5-year OS rates were 82.9% and 76.7% (p = 0.620) in the BTS and ES groups, respectively. No tumor recurrence was found in the BTS group but seven recurrences were found in the ES group (11.7%) [p = 0.091]. Laparoscopic surgery was chosen by 42.9% of patients in the BTS group and 26.7% of patients in the ES group (p = 0.104); however, the length of hospital stay (p = 0.001) was longer in the BTS group. CONCLUSIONS: In the two groups, no differences were found in terms of postoperative complications and mortality as well as OS. The BTS group preferred to perform laparoscopic surgery and the technical success rate of stenting was high, therefore SEMS for RCCO was considered safe and feasible.

Payer-Negotiated Price Variation and Relationship to Surgical Outcomes for the Most Common Cancers at NCI-Designated Cancer Centers.

BACKGROUND: Federal rules mandate that hospitals publish payer-specific negotiated prices for all services. Little is known about variation in payer-negotiated prices for surgical oncology services or their relationship to clinical outcomes. We assessed variation in payer-negotiated prices associated with surgical care for common cancers at National Cancer Institute (NCI)-designated cancer centers and determined the effect of increasing payer-negotiated prices on the odds of morbidity and mortality. MATERIALS AND METHODS: A cross-sectional analysis of 63 NCI-designated cancer center websites was employed to assess variation in payer-negotiated prices. A retrospective cohort study of 15,013 Medicare beneficiaries undergoing surgery for colon, pancreas, or lung cancers at an NCI-designated cancer center between 2014 and 2018 was conducted to determine the relationship between payer-negotiated prices and clinical outcomes. The primary outcome was the effect of median payer-negotiated price on odds of a composite outcome of 30 days mortality and serious postoperative complications for each cancer cohort. RESULTS: Within-center prices differed by up to 48.8-fold, and between-center prices differed by up to 675-fold after accounting for geographic variation in costs of providing care. Among the 15,013 patients discharged from 20 different NCI-designated cancer centers, the effect of normalized median payer-negotiated price on the composite outcome was clinically negligible, but statistically significantly positive for colon [aOR 1.0094 (95% CI 1.0051-1.0138)], lung [aOR 1.0145 (1.0083-1.0206)], and pancreas [aOR 1.0080 (1.0040-1.0120)] cancer cohorts. CONCLUSIONS: Payer-negotiated prices are statistically significantly but not clinically meaningfully related to morbidity and mortality for the surgical treatment of common cancers. Higher payer-negotiated prices are likely due to factors other than clinical quality.

Nationwide standardization of minimally invasive right hemicolectomy for colon cancer and development and validation of a video-based competency assessment tool (the Right study).

BACKGROUND: Substantial variation exists when performing a minimally invasive right hemicolectomy (MIRH) due to disparities in training, expertise and differences in implementation of innovations. This study aimed to achieve national consensus on an optimal and standardized MIRH technique for colon cancer and to develop and validate a video-based competency assessment tool (CAT) for MIRH. METHOD: Statements covering all elements of MIRH were formulated. Subsequently, the Delphi technique was used to reach consensus on a standardized MIRH among 76 colorectal surgeons from 43 different centres. A CAT was developed based on the Delphi results. Nine surgeons assessed the same 12 unedited full-length videos using the CAT, allowing evaluation of the intraclass correlation coefficient (ICC). RESULTS: After three Delphi rounds, consensus (≥80% agreement) was achieved on 23 of the 24 statements. Consensus statements included the use of low intra-abdominal pressure, detailed anatomical outline how to perform complete mesocolic excision with central vascular ligation, the creation of an intracorporeal anastomosis, and specimen extraction through a Pfannenstiel incision using a wound protector. The CAT included seven consecutive steps to measure competency of the MIRH and showed high consistency among surgeons with an overall ICC of 0.923. CONCLUSION: Nationwide consensus on a standardized and optimized technique of MIRH was reached. The CAT developed showed excellent interrater reliability. These achievements are crucial steps to an ongoing nationwide quality improvement project (the Right study).

Surgical stress response in robot-assisted versus laparoscopic surgery for colon cancer (SIRIRALS): randomized clinical trial.

BACKGROUND: Evidence for the routine use of robotic technology and its impact on short-term outcomes in colon cancer surgery is lacking. The aim of this study was to compare the surgically induced systemic stress response and clinical and patient-reported outcomes for patients undergoing robot-assisted or laparoscopic colon cancer surgery. METHODS: In this double-blinded superiority RCT completed between August 2021 and March 2023, patients with stage 1-3 colon cancer were randomized in a 1 : 1 ratio to undergo either robot-assisted or laparoscopic colon cancer surgery. The primary outcome was changes in the systemic stress response, characterized by C-reactive protein expression in the first three postoperative days. Secondary outcomes were intraoperative and postoperative complications and patient-reported outcomes. The latter included quality of recovery-15 and pain intensity using a visual analogue scale. RESULTS: In total, 128 patients were screened for potential inclusion in this study; 50 patients (25 in the robot-assisted group and 25 in the laparoscopic group) were included in the final follow-up and analysis. The postoperative C-reactive protein response was higher on the first postoperative day in the laparoscopic group (mean difference = 19.88 mg/l, 95% c.i. 3.89-35.86; P = 0.045). No statistically significant differences were noted for C-reactive protein expression on the second and third postoperative days. CONCLUSION: Adopting robot-assisted surgery for stage 1-3 colon cancer is associated with a reduction in the surgical stress response. REGISTRATION NUMBER: NCT04687384 (http://www.clinicaltrials.gov).

Survival and safety after neoadjuvant chemotherapy or upfront surgery for locally advanced colon cancer: meta-analysis.

BACKGROUND: Neoadjuvant chemotherapy is increasingly used to treat locally advanced (T3-4 Nx-2 M0) colon cancer due to its potential advantages over the standard approach of upfront surgery. The primary objective of this systematic review and meta-analysis was to analyse data from comparative studies to assess the impact of neoadjuvant chemotherapy on oncological outcomes. METHODS: A systematic review was conducted by searching the MEDLINE and Scopus databases. The search encompassed RCTs, propensity score-matched studies, and controlled prospective studies published up to 1 April 2023. As a primary objective, overall survival and disease-free survival were compared. As a secondary objective, perioperative morbidity, mortality, and complete resection were compared using the DerSimonian and Laird models. RESULTS: A total of seven studies comprising a total of 2120 patients were included. Neoadjuvant chemotherapy was associated with a reduction in the hazard of recurrence (HR 0.73, 95% c.i. 0.59 to 0.90; P = 0.003) and death (HR 0.67, 95% c.i. 0.54 to 0.83; P < 0.001) compared with upfront surgery. Additionally, neoadjuvant chemotherapy was significantly associated with higher 5-year overall survival (79.9% versus 72.6%; P < 0.001) and disease-free survival (73.1% versus 64.5%; P = 0.028) rates. No significant differences were observed in perioperative mortality (OR 0.97, 95% c.i. 0.28 to 3.33), overall complications (OR 0.95, 95% c.i. 0.77 to 1.16), or anastomotic leakage/intra-abdominal abscess (OR 0.88, 95% c.i. 0.60 to 1.29). However, neoadjuvant chemotherapy was associated with a lower risk of incomplete resection (OR 0.70, 95% c.i. 0.49 to 0.99). CONCLUSION: Neoadjuvant chemotherapy is associated with a reduced hazard of recurrence and death, as well as improved overall survival and disease-free survival rates, compared with upfront surgery in patients with locally advanced colon cancer.

Colon cancer is a common medical condition, the established treatment for which involves surgical resection followed by chemotherapy. However, a contemporary shift has led to the investigation of an alternative treatment sequence known as neoadjuvant chemotherapy, wherein chemotherapy precedes the surgery. This study critically assesses the efficacy of neoadjuvant chemotherapy compared with the standard treatment approach of surgery followed by chemotherapy. A systematic review of medical databases was undertaken to identify pertinent research publications on this subject matter. In total, seven studies encompassing data from 2120 patients were included in the analysis. Employing a meta-analysis methodology to synthesize the collective data from these studies, it was revealed that neoadjuvant chemotherapy was linked to higher rates of 5-year overall survival and disease-free survival, alongside a diminished hazard of both recurrence and death. Furthermore, no discernible differences in surgical complications or perioperative mortality were evident across the compared approaches.

Accelerated enhanced recovery after colon cancer surgery with discharge within one day after surgery: a systematic review.

BACKGROUND: Recent studies have demonstrated that accelerated enhanced recovery after colorectal surgery is feasible for specific patient populations. The accelerated enhanced recovery protocols (ERP) tend to vary, and the majority of studies included a small study population. This hampers defining the optimal protocol and establishing the potential benefits. This systematic review aimed to determine the effect of accelerated ERPs with intended discharge within one day after surgery. METHODS: PubMed (MEDLINE), Embase, Cochrane and Web of Science databases were searched using the following search terms: colon cancer, colon surgery, accelerated recovery, fast track recovery, enhanced recovery after surgery. Clinical trials published between January 2005 - February 2023, written in English or Dutch comparing accelerated ERPs to Enhanced Recovery After Surgery (ERAS) care for adult patients undergoing elective laparoscopic or robotic surgery for colon cancer were eligible for inclusion. RESULTS: Thirteen studies, including one RCT were included. Accelerated ERPs after colorectal surgery was possible as LOS was shorter; 14 h to 3.4 days, and complication rate varied from 0-35.7% and readmission rate was 0-17% in the accelerated ERP groups. Risk of bias was serious or critical in most of the included studies. CONCLUSIONS: Accelerated ERPs may not yet be considered the new standard of care as the current data is heterogenous, and data on important outcome measures is scarce. Nonetheless, the decreased LOS suggests that accelerated recovery is possible for selected patients. In addition, the complication and readmission rates were comparable to ERAS care, suggesting that accelerated recovery could be safe.

The effects of oxaliplatin-based adjuvant chemotherapy in high-risk stage II colon cancer with mismatch repair-deficient: a retrospective study.

BACKGROUND: For high-risk stageIImismatch repair deficient (dMMR) colon cancers, the benefit of adjuvant chemotherapy remains debatable. The principal aim of this study was to evaluate the prognostic value of high-risk factors and the effect of oxaliplatin-based adjuvant chemotherapy among dMMR stageIIcolon cancers. METHODS: Patients with stage II dMMR colon cancers diagnosed between June 2011 and May 2018 were enrolled in the study. Clinicopathological characteristics, treatment, and follow-up data were retrospectively collected. The high-risk group was defined as having one of the following factors: pT4 disease, fewer than twelve lymph nodes harvested (< 12 LNs), poorly differentiated histology, perineural invasion (PNI), lymphatic vascular invasion (LVI), or elevated preoperative carcinoembryonic antigen (CEA). The low-risk group did not have any risk factors above. Factors associated with disease-free survival (DFS) were included in univariate and multivariate Cox analyses. RESULTS: We collected a total of 262 consecutive patients with stage II dMMR colon cancer. 179 patients (68.3%) have at least one high-risk factor. With a median follow-up of 50.1 months, the low-risk group was associated with a tended to have a better 3-year DFS than the high-risk group (96.4% vs 89.4%; P = 0.056). Both elevated preoperative CEA (HR 2.93; 95% CI 1.26-6.82; P = 0.013) and pT4 disease (HR 2.58; 95% CI 1.06-6.25; P = 0.037) were independent risk factors of recurrence. Then, the 3-year DFS was 92.6% for the surgery alone group and 88.1% for the adjuvant chemotherapy group (HR 1.64; 95% CI 0.67-4.02; P = 0.280). Furthermore, no survival benefit from oxaliplatin-based adjuvant chemotherapy was observed in the high-risk group and in the subgroups with pT4 disease or < 12 LNs. CONCLUSIONS: These data suggests that not all high-risk factors have a similar impact on stage II dMMR colon cancers. Elevated preoperative CEA and pT4 tumor stage are associated with increased recurrence risk. However, oxaliplatin-based adjuvant chemotherapy shows no survival benefits in stage II dMMR colon cancers, either with or without high-risk factors.

A simplified algorithm to evaluate the risk of submucosal invasive cancer in large (≥20 mm) nonpedunculated colonic polyps.

BACKGROUND: Recognition of submucosal invasive cancer (SMIC) in large (≥20 mm) nonpedunculated colonic polyps (LNPCPs) informs selection of the optimal resection strategy. LNPCP location, morphology, and size influence the risk of SMIC; however, currently no meaningful application of this information has simplified the process to make it accessible and broadly applicable. We developed a decision-making algorithm to simplify the identification of LNPCP subtypes with increased risk of potential SMIC. METHODS: Patients referred for LNPCP resection from September 2008 to November 2022 were enrolled. LNPCPs with SMIC were identified from endoscopic resection specimens, lesion biopsies, or surgical outcomes. Decision tree analysis of lesion characteristics identified in multivariable analysis was used to create a hierarchical classification of SMIC prevalence. RESULTS: 2451 LNPCPs were analyzed: 1289 (52.6%) were flat, 1043 (42.6%) nodular, and 118 (4.8%) depressed. SMIC was confirmed in 273 of the LNPCPs (11.1%). It was associated with depressed and nodular vs. flat morphology (odds ratios [ORs] 35.7 [95%CI 22.6-56.5] and 3.5 [95%CI 2.6-4.9], respectively; P<0.001); rectosigmoid vs. proximal location (OR 3.2 [95%CI 2.5-4.1]; P<0.001); nongranular vs. granular appearance (OR 2.4 [95%CI 1.9-3.1]; P<0.001); and size (OR 1.12 per 10-mm increase [95%CI 1.05-1.19]; P<0.001). Decision tree analysis targeting SMIC identified eight terminal nodes: SMIC prevalence was 62% in depressed LNPCPs, 19% in nodular rectosigmoid LNPCPs, and 20% in nodular proximal colon nongranular LNPCPs. CONCLUSIONS: This decision-making algorithm simplifies identification of LNPCPs with an increased risk of potential SMIC. When combined with surface optical evaluation, it facilitates accurate lesion characterization and resection choices.

Two Types of Variational Arteries' Courses From the Superior Mesenteric Artery to Supply the Splenic Flexure: Gross Anatomical Study.

BACKGROUND: Complete mesocolic excision with central vascular ligation is a standard method for managing colon cancer. However, there is no consensus on its procedure, especially for cancer in the splenic flexure of the transverse colon. This is because various types of variational arteries are distributed to the region, and their running course below and near the pancreas leads to difficulty in ligating the artery. OBJECTIVE: To clarify the arterial distribution to the splenic flexure of the transverse colon using cadavers. DESIGN: The arteries in the transverse mesocolon distributed to the colon were dissected in cadavers, and their route was quantitatively visualized using drawing software. SETTINGS: This study was conducted at the Department of Anatomy, Tokyo Medical University. PATIENTS: Sixty cadavers donated to Tokyo Medical University in 2017-2021 were used. MAIN OUTCOME MEASURES: The arterial courses to the splenic flexure of the transverse colon in the mesocolon and their patterns were evaluated. RESULTS: We found 34 variational arteries distributed to the splenic flexure of the transverse colon. Most originated from the superior mesenteric artery and the middle colic artery, with their typical course below the pancreas. We identified another arterial course, crossing the mesocolon away from the pancreas toward the splenic flexure of the transverse colon. Furthermore, the origin of these arteries was not behind the pancreas and can be found in the caudal region of the pancreas. LIMITATIONS: We cannot discuss how the arteries within the transverse mesocolon are observed by CT examination. CONCLUSIONS: This study showed 2 types of arterial courses (below the pancreas and within the mesocolon) toward the splenic flexure of the transverse colon for the first time. In the latter case, the complete mesocolic excision with central vascular ligation is likely performed more easily than in the former. See Video Abstract. DOS TIPOS DE RECORRIDO VARIACIONAL DE LA ARTERIA DESDE LA ARTERIA MESENTRICA SUPERIOR PARA IRRIGAR EL NGULO ESPLNICO ESTUDIO ANATMICO MACROSCPICO: ANTECEDENTES:La escisión mesocólica completa con ligadura vascular central es un método estándar para el cáncer de colon. Sin embargo, no hay consenso sobre su procedimiento, especialmente para el cáncer en el ángulo esplénico del colon transverso. Esto se debe a que varios tipos de arterias variacionales se distribuyen en la región, y su recorrido por debajo y cerca del páncreas dificulta la ligadura de la arteria.OBJETIVO:Este estudio tuvo como objetivo aclarar la distribución arterial al SF del colon transverso utilizando cadáveres.DISEÑO:Las arterias en el mesocolon transverso distribuidas al colon fueron disecadas en cadáveres, y su ruta fue visualizada cuantitativamente utilizando un software de dibujo.AJUSTES:Este estudio se realizó en el Departamento de Anatomía de la Universidad Médica de Tokio.PACIENTES:Se utilizaron sesenta cadáveres donados a la Universidad Médica de Tokio en 2017-2021.PRINCIPALES MEDIDAS DE RESULTADO:Se evaluaron los cursos arteriales al ángulo esplénico del colon transverso en el mesocolon y sus patrones.RESULTADOS:Encontramos 34 arterias variacionales distribuidas al ángulo esplénico del colon transverso. La mayoría se originaron en la arteria mesentérica superior y la arteria cólica media, con su trayecto típico por debajo del páncreas. Identificamos otro curso arterial, cruzando el mesocolon alejándose del páncreas hacia el ángulo esplénico del colon transverso. Además, el origen de estas arterias no estaba detrás del páncreas y se pueden encontrar en la región caudal del páncreas.LIMITACIONES:No podemos discutir cómo se observan las arterias dentro del mesocolon transverso mediante un examen de tomografía computarizada.CONCLUSIONES:Este estudio mostró por primera vez dos tipos de trayectos arteriales (por debajo del páncreas y dentro del mesocolon) hacia el ángulo esplénico del colon transverso. En el último caso, es probable que la escisión mesocólica completa con ligadura vascular central se realice más fácilmente que en el primero. (Traducción-Dr. Aurian Garcia Gonzalez ).

Validation of a Clinical Calculator Predicting Freedom From Colon Cancer Recurrence After Surgery on the Basis of Molecular and Clinical Variables.

BACKGROUND: The Memorial Sloan Kettering clinical calculator for estimating the likelihood of freedom from colon cancer recurrence on the basis of clinical and molecular variables was developed at a time when testing for microsatellite instability was performed selectively, based on patient age, family history, and histologic features. Microsatellite stability was assumed if no testing was done. OBJECTIVE: This study aimed to validate the calculator in a cohort of patients who had all been tested for microsatellite instability. DESIGN: Retrospective cohort analysis. SETTINGS: Comprehensive cancer center. PATIENTS: This study included consecutive patients who underwent curative resection for stage I, II, or III colon cancer between 2017 and 2019. INTERVENTION: Universal testing of mircrosatellite phenotype in all cases. MAIN OUTCOME MEASURES: The calculator's predictive accuracy was assessed using the concordance index and a calibration plot of predicted versus actual freedom from recurrence at 3 years after surgery. For a secondary sensitivity analysis, the presence of a tumor deposit(s) (disease category N1c) was considered equivalent to one positive lymph node (category N1a). RESULTS: With a median follow-up of 32 months among survivors, the concordance index for the 745 patients in the cohort was 0.748 (95% CI, 0.693-0.801), and a plot of predicted versus observed recurrences approached the 45° diagonal, indicating good discrimination and calibration. In the secondary sensitivity analysis for tumor deposits, the concordance index was 0.755 (95% CI, 0.700-0.806). LIMITATIONS: This study was limited by its retrospective, single-institution design. CONCLUSIONS: These results, based on inclusion of actual rather than imputed microsatellite stability status and presence of tumor deposits, confirm the predictive accuracy and reliability of the calculator. See Video Abstract . VALIDACIN DE UNA CALCULADORA CLNICA QUE PREDICE LA AUSENCIA DE RECURRENCIA POSTQUIRURGICA DEL CNCER DE COLON SOBRE LA BASE DE VARIABLES MOLECULARES Y CLNICAS: ANTECEDENTES:La calculadora clínica del Memorial Sloan Kettering para la estimación de la probabilidad de ausencia de recurrencia del cáncer de colon sobre la base de variables clínicas y moleculares, se desarrolló en un momento en que las pruebas para la inestabilidad de microsatélites se realizaban de forma selectiva, basadas en la edad del paciente, los antecedentes familiares y las características histológicas. Se asumía la estabilidad micro satelital si no se realizaba ninguna prueba.OBJETIVO:El objetivo de este estudio fue validar la calculadora en una cohorte de pacientes a los que se les había realizado la prueba de inestabilidad de microsatélites.DISEÑO:Análisis de cohorte retrospectivo.AJUSTE:Centro integral de cáncer.PACIENTES:Pacientes consecutivos con cáncer de colon que fueron sometidos a resección curativa por cáncer de colon en estadios I, II o III entre los años 2017 y 2019.PRINCIPALES MEDIDAS DE RESULTADO:La precisión predictiva de la calculadora fue evaluada mediante el índice de concordancia y un gráfico de calibración de la ausencia de recurrencia predecida versus la real a los 3 años tras la cirugía. A los efectos de un análisis secundario de sensibilidad, la presencia de depósito(s) tumoral(es) (categoría de enfermedad N1c) se consideró equivalente a un ganglio linfático positivo (categoría N1a).RESULTADOS:Con una mediana de seguimiento de 32 meses entre los supervivientes, el índice de concordancia para los 745 pacientes de la cohorte fue de 0,748 (intervalo de confianza del 95 %, 0,693 a 0,801), y una gráfica de recurrencias previstas versus observadas se acercó a la diagonal de 45°, indicando una buena discriminación y calibración. En el análisis secundario de sensibilidad para depósitos tumorales, el índice de concordancia fue de 0,755 (intervalo de confianza del 95 %, 0,700 a 0,806).LIMITACIONES:Diseño retrospectivo, institución única.CONCLUSIONES:Estos resultados, basados en la inclusión real del estado de estabilidad de microsatélites en lugar de imputado y la presencia de depósitos tumorales, confirman la precisión predictiva y la confiabilidad de la calculadora. (Traducción-Dr Osvaldo Gauto ).

Management Strategies for Malignant Left-Sided Colonic Obstruction: A Systematic Review and Network Meta-analysis of Randomized Controlled Trials and Propensity Score Matching Studies.

BACKGROUND: The optimal treatment strategy for left-sided malignant colonic obstruction remains controversial. Emergency colonic resection has been the standard of care; however, self-expanding metallic stenting as a bridge to surgery may offer short-term advantages, although oncological concerns exist. Decompressing stoma may provide a valid alternative, with limited evidence. OBJECTIVE: To perform a systematic review and Bayesian arm random-effects model network meta-analysis comparing the approaches for management of malignant left-sided colonic obstruction. DATA SOURCES: A systematic review of PubMed, Embase, Cochrane Library, and Google Scholar databases was conducted from inception to August 22, 2023. STUDY SELECTION: Randomized controlled trials and propensity score-matched studies. INTERVENTIONS: Emergency colonic resection, self-expanding metallic stent, and decompressing stoma. MAIN OUTCOME MEASURES: Oncologic efficacy, morbidity, successful minimally invasive surgery, primary anastomosis, and permanent stoma rates. RESULTS: Nineteen of 5225 articles identified met our inclusion criteria. Stenting (risk ratio 0.57; 95% credible interval, 0.33-0.79) and decompressing stomas (risk ratio 0.46, 95% credible interval: 0.18-0.92) resulted in a significant reduction in the permanent stoma rate. Stenting facilitated minimally invasive surgery more frequently (risk ratio 4.10; 95% credible interval, 1.45-13.13) and had lower overall morbidity (risk ratio 0.58; 95% credible interval, 0.35-0.86). A pairwise analysis of primary anastomosis rates showed increased stenting (risk ratio 1.40; 95% credible interval, 1.31-1.49) compared with emergency resection. There was a significant decrease in the 90-day mortality with stenting (risk ratio 0.63; 95% credible interval, 0.41-0.95) compared with resection. There were no differences in disease-free and overall survival rates, respectively. LIMITATIONS: There is a lack of randomized controlled trials and propensity score matching data comparing short-term and long-term outcomes for diverting stomas compared to self-expanding metallic stents. Two trials compared self-expanding metallic stents and diverting stomas in left-sided malignant colonic obstruction. CONCLUSIONS: This study provides high-level evidence that a bridge-to-surgery strategy is safe for the management of left-sided malignant colonic obstruction and may facilitate minimally invasive surgery, increase primary anastomosis rates, and reduce permanent stoma rates and postoperative morbidity compared with emergency colonic resection.

Predicting Colonic Neoplasia Surgical Complications: A Machine Learning Approach.

BACKGROUND: A range of statistical approaches have been used to help predict outcomes associated with colectomy. The multifactorial nature of complications suggests that machine learning algorithms may be more accurate in determining postoperative outcomes by detecting nonlinear associations, which are not readily measured by traditional statistics. OBJECTIVE: The aim of this study was to investigate the utility of machine learning algorithms to predict complications in patients undergoing colectomy for colonic neoplasia. DESIGN: Retrospective analysis using decision tree, random forest, and artificial neural network classifiers to predict postoperative outcomes. SETTINGS: National Inpatient Sample database (2003-2017). PATIENTS: Adult patients who underwent elective colectomy with anastomosis for neoplasia. MAIN OUTCOME MEASURES: Performance was quantified using sensitivity, specificity, accuracy, and area under the receiver operating characteristic curve to predict the incidence of anastomotic leak, prolonged length of stay, and inpatient mortality. RESULTS: A total of 14,935 patients (4731 laparoscopic, 10,204 open) were included. They had an average age of 67 ± 12.2 years, and 53% of patients were women. The 3 machine learning models successfully identified patients who developed the measured complications. Although differences between model performances were largely insignificant, the neural network scored highest for most outcomes: predicting anastomotic leak, area under the receiver operating characteristic curve 0.88/0.93 (open/laparoscopic, 95% CI, 0.73-0.92/0.80-0.96); prolonged length of stay, area under the receiver operating characteristic curve 0.84/0.88 (open/laparoscopic, 95% CI, 0.82-0.85/0.85-0.91); and inpatient mortality, area under the receiver operating characteristic curve 0.90/0.92 (open/laparoscopic, 95% CI, 0.85-0.96/0.86-0.98). LIMITATIONS: The patients from the National Inpatient Sample database may not be an accurate sample of the population of all patients undergoing colectomy for colonic neoplasia and does not account for specific institutional and patient factors. CONCLUSIONS: Machine learning predicted postoperative complications in patients with colonic neoplasia undergoing colectomy with good performance. Although validation using external data and optimization of data quality will be required, these machine learning tools show great promise in assisting surgeons with risk-stratification of perioperative care to improve postoperative outcomes. See Video Abstract . PREDICCIN DE LAS COMPLICACIONES QUIRRGICAS DE LA NEOPLASIA DE COLON UN ENFOQUE DE MODELO DE APRENDIZAJE AUTOMTICO: ANTECEDENTES:Se han utilizado una variedad de enfoques estadísticos para ayudar a predecir los resultados asociados con la colectomía. La naturaleza multifactorial de las complicaciones sugiere que los algoritmos de aprendizaje automático pueden ser más precisos en determinar los resultados posoperatorios al detectar asociaciones no lineales, que generalmente no se miden en las estadísticas tradicionales.OBJETIVO:El objetivo de este estudio fue investigar la utilidad de los algoritmos de aprendizaje automático para predecir complicaciones en pacientes sometidos a colectomía por neoplasia de colon.DISEÑO:Análisis retrospectivo utilizando clasificadores de árboles de decisión, bosques aleatorios y redes neuronales artificiales para predecir los resultados posoperatorios.AJUSTE:Base de datos de la Muestra Nacional de Pacientes Hospitalizados (2003-2017).PACIENTES:Pacientes adultos sometidos a colectomía electiva con anastomosis por neoplasia.INTERVENCIONES:N/A.PRINCIPALES MEDIDAS DE RESULTADO:El rendimiento se cuantificó utilizando la sensibilidad, especificidad, precisión y la característica operativa del receptor del área bajo la curva para predecir la incidencia de fuga anastomótica, duración prolongada de la estancia hospitalaria y mortalidad de los pacientes hospitalizados.RESULTADOS:Se incluyeron un total de 14.935 pacientes (4.731 laparoscópicos, 10.204 abiertos). Presentaron una edad promedio de 67 ± 12,2 años y el 53% eran mujeres. Los tres modelos de aprendizaje automático identificaron con éxito a los pacientes que desarrollaron las complicaciones medidas. Aunque las diferencias entre el rendimiento del modelo fueron en gran medida insignificantes, la red neuronal obtuvo la puntuación más alta para la mayoría de los resultados: predicción de fuga anastomótica, característica operativa del receptor del área bajo la curva 0,88/0,93 (abierta/laparoscópica, IC del 95%: 0,73-0,92/0,80-0,96); duración prolongada de la estancia hospitalaria, característica operativa del receptor del área bajo la curva 0,84/0,88 (abierta/laparoscópica, IC del 95%: 0,82-0,85/0,85-0,91); y mortalidad de pacientes hospitalizados, característica operativa del receptor del área bajo la curva 0,90/0,92 (abierto/laparoscópico, IC del 95%: 0,85-0,96/0,86-0,98).LIMITACIONES:Los pacientes de la base de datos de la Muestra Nacional de Pacientes Hospitalizados pueden no ser una muestra precisa de la población de todos los pacientes sometidos a colectomía por neoplasia de colon y no tienen en cuenta factores institucionales y específicos del paciente.CONCLUSIONES:El aprendizaje automático predijo con buen rendimiento las complicaciones postoperatorias en pacientes con neoplasia de colon sometidos a colectomía. Aunque será necesaria la validación mediante datos externos y la optimización de la calidad de los datos, estas herramientas de aprendizaje automático son muy prometedoras para ayudar a los cirujanos con la estratificación de riesgos de la atención perioperatoria para mejorar los resultados posoperatorios. (Traducción-Dr. Fidel Ruiz Healy ).

Pulmonary Metastasis as the First Site of Metastasis After Curative Surgery for Colon Cancer: Incidence and Risk Factors According to the TNM Stage.

BACKGROUND: The lungs are one of the most common sites for colon cancer metastasis. A few studies reported that approximately 2% to 10% of patients with colon cancer developed pulmonary metastasis. However, among these studies, patient characteristics were heterogeneous, and information on pulmonary metastasis incidence by the TNM stage was scarce. OBJECTIVE: This study evaluated the incidence of pulmonary metastasis in colon cancer without synchronous metastasis treated with radical surgery and identified risk factors for pulmonary metastasis according to the TNM stage. DESIGN AND SETTINGS: This retrospective study included all patients with colon cancer without metastasis who underwent radical surgery for primary tumor at Samsung Medical Center between January 2007 and December 2016. PATIENTS: A total of 4889 patients who underwent radical surgery for stage I and III colon cancer were included. MAIN OUTCOME MEASURES: The main outcome measures were the incidence of pulmonary metastasis and overall survival. RESULTS: A total of 156 patients (3.2%) were diagnosed with pulmonary metastasis after a median of 16 months from the time of radical surgery for colon cancer to detection of pulmonary metastasis. The pulmonary metastasis incidence rate by the TNM stage was 0.5% in stage I, 1.6% in stage II, and 6% in stage III. Risk factors for pulmonary metastasis were preoperative CEA >5 ng/mL, cancer obstruction, N stage, vascular invasion, perineural invasion, and adjuvant chemotherapy for primary colon cancer in multivariable analysis. LIMITATION: This was a retrospective single-center study. CONCLUSIONS: Preoperative CEA >5 ng/mL, cancer obstruction, pN stage, vascular invasion, perineural invasion, and receiving adjuvant chemotherapy for primary colon cancer were risk factors for pulmonary metastasis in colon cancer. Therefore, patients with risk factors for pulmonary metastasis should be recommended for intensive follow-up to detect lung metastases. See Video Abstract . METSTASIS PULMONAR EN EL PRIMER SITIO TRAS CIRUGA CURATIVA DEL CNCER DE COLON INCIDENCIA Y FACTORES DE RIESGO SEGN ESTADIO TNM: ANTECEDENTES:Los pulmones son uno de los sitios más comunes de metástasis del cáncer de colon. Algunos estudios informaron que aproximadamente entre el 2% y el 10% de los pacientes con cáncer de colon desarrollaron metástasis pulmonar. Sin embargo, entre estos estudios, las características de los pacientes fueron heterogéneas y la información sobre la incidencia de metástasis pulmonares según el estadio TNM fue escasa.OBJETIVO:Este estudio evaluó la incidencia de metástasis pulmonar en cáncer de colon sin metástasis sincrónica tratada con cirugía radical e identificó factores de riesgo para metástasis pulmonar según el estadio TNM.DISEÑO Y AJUSTES:Este estudio retrospectivo incluyó a todos los pacientes con cáncer de colon sin metástasis que se sometieron a cirugía radical por tumor primario en el Samsung Medical Center entre enero de 2007 y diciembre de 2016.PACIENTES:Se incluyó un total de 4.889 pacientes sometidos a cirugía radical por cáncer de colon en estadio I-III.PRINCIPALES MEDIDAS DE RESULTADO:Las principales medidas de resultado fueron la incidencia de metástasis pulmonar y la supervivencia general.RESULTADOS:Un total de 156 pacientes (3,2%) fueron diagnosticados con metástasis pulmonar con una duración media de 16 meses desde el momento de la cirugía radical por cáncer de colon hasta la detección de la metástasis pulmonar. La tasa de incidencia de metástasis pulmonares por estadio TNM fue del 0,5% en el estadio I, del 1,6% en el estadio II y del 6% en el estadio III. Los factores de riesgo de metástasis pulmonar fueron CEA preoperatorio superior a 5 ng/ml, obstrucción por cáncer, estadio N, invasión vascular, invasión perineural y quimioterapia adyuvante para el cáncer de colon primario en un análisis multivariable.LIMITACIÓN:Este fue un estudio retrospectivo de un solo centro.CONCLUSIÓN:CEA preoperatorio superior a 5 ng/ml, obstrucción por cáncer, estadio pN, invasión vascular, invasión perineural y recibir quimioterapia adyuvante para el cáncer de colon primario fueron factores de riesgo de metástasis pulmonar en el cáncer de colon. Por lo tanto, se debe recomendar un seguimiento intensivo a los pacientes con factores de riesgo de metástasis pulmonares para detectar metástasis pulmonares. (Traducción-Dr Yolanda Colorado ).

Robotic True D3 Lymph Node Dissection With Superior Mesenteric Vein-Taping Technique for Right-Sided Colon Cancer.

BACKGROUND: D3 is unaffected by anatomic factors even when the ileocolic artery runs along the dorsal side of the superior mesenteric vein. Complete "true D3" lymph node dissection in minimally invasive surgery for right-sided colon cancer could be beneficial for certain patients with lymph node metastases. IMPACT OF INNOVATION: The study aimed to determine the safety and feasibility of robotic true D3 lymph node dissection for right-sided colon cancer using a superior mesenteric vein-taping technique. TECHNOLOGY, MATERIALS, AND METHODS: The superior mesenteric vein was slowly and gently separated from the surrounding tissues and taped. Lifting the tape with the robotic third arm and fixing it in place using rock-stable tractions provides a good surgical view, which cannot otherwise be obtained. As a result, the ileocolic artery that branches from the superior mesenteric artery can be accurately exposed. Handling of the taping then enables expansion to a different surgical view. As the lymph nodes are originally concealed on the dorsal side of the superior mesenteric vein, this technique provides a good view for lymph node dissection. The root of the ileocolic artery was clipped and separated, and true D3 was thus completed. PRELIMINARY RESULTS: Fourteen patients underwent robotic true D3 lymph node dissection for right-sided colon cancer. No Clavien-Dindo classification grade II or higher intraoperative or postoperative complications were observed. The 30-day mortality rate was 0%. CONCLUSIONS: Our robotic true D3 lymph node dissection with superior mesenteric vein-taping technique is considered safe and feasible; it might be a promising surgical procedure for treating advanced right-sided colon cancer. FUTURE DIRECTIONS: Even when the ileocolic artery runs along the dorsal aspect of the superior mesenteric vein, the technique seems promising for facilitating robotic D3 lymph node dissection.

Maximizing Readmission Reduction in Colon Cancer Patients.

INTRODUCTION: Multiple studies have identified risk factors for readmission in colon cancer patients. We need to determine which risk factors, when modified, produce the greatest decrease in readmission for patients so that limited resources can be used most effectively by implementing targeted evidence-based performance improvements. We determined the potential impact of various modifiable risk factors on reducing 30-d readmission in colon cancer patients. METHODS: We used a cohort design with the 2012-2020 American College of Surgeons' National Surgical Quality Improvement Program data to track colon cancer patients for 30 d following surgery. Colon cancer patients who received colectomies and were discharged alive were included. Readmission (to the same or another hospital) for any reason within 30 d of the resection was the outcome measure. Modifiable risk factors were the use of minimally invasive surgery (MIS) versus open colectomy, mechanical bowel preparation, preoperative antibiotic use, functional status, smoking, complications (deep vein thrombosis, pulmonary embolism, myocardial infarction, stroke, infections, anastomotic leakage, prolonged postoperative ileus, extensive blood loss, and sepsis), serum albumin, and hematocrit. RESULTS: 111,691 patients with colon cancer were included in the analysis. About half of the patients were male, most were aged 75 or older, and were discharged home. Overall, 11,138 patients (10.0%) were readmitted within 30 d of surgery. In adjusted analysis, the reduction in readmission would be largest by preventing both prolonged ileus and by switching open colectomies to MIS (28.0% relative reduction) followed by preventing anastomotic leaks (6.2% relative reduction). Improving other modifiable risk factors would have a more limited impact. CONCLUSIONS: The focus of readmission reduction should be on preventing prolonged ileus, increasing the use of MIS, and preventing anastomotic leaks.