The incidence of venous thromboembolism after curative colon cancer surgery within an enhanced recovery after surgery programme.

AIM: Based on three randomised controlled trials performed more than a decade ago, several national guidelines recommend prolonged venous thromboprophylaxis for 28 days following elective surgery for colon cancer. None of these studies were conducted within enhanced recovery after surgery setting. Newer studies indicate that prolonged prophylaxis might not be necessary with enhanced recovery after surgery. We aimed to provide further evidence to this unresolved discussion. METHOD: Retrospective study of patients undergoing elective surgery for colon cancer stage I-III with enhanced recovery after surgery in the Capital Region of Denmark from 2014 to 2017. Patients were excluded if discharged on postoperative day 28 or later, dying before discharge, undergoing concomitant rectum resection, or discharged with vitamin K antagonists, direct-oral anticoagulants, or low molecular weight heparin treatment. All patients received only low-dose low molecular weight heparin as prophylaxis during their admission. The primary endpoint was symptomatic lower limb deep venous thrombosis or pulmonary embolism diagnosed within 60 days postoperatively. RESULTS: Out of the included population of 1806 patients, only three experienced a symptomatic venous thromboembolic event; none was fatal. Two had pulmonary embolism associated with pneumonia, while one patient was diagnosed with lower limb deep venous thrombosis at postoperative day 15 after an uncomplicated course with first discharge at postoperative day 2. CONCLUSION: The risk of symptomatic venous thromboembolism after elective surgery for colon cancer with enhanced recovery after surgery seems negligible even without prolonged prophylaxis. The current guidelines need to be reconsidered.

Validation of the German classification system for quality assessment of right-sided colon cancer specimens.

AIM: The German classification system of the completeness of mesocolic excision aims to assess the quality of right-sided colonic cancer surgery by review of photographs. We aimed to validate the reliability of the classification in a clinical context. METHOD: The study was based on a cohort of patients undergoing resection for right-sided colon cancer in two university hospitals served by the same group of pathologists. Prospectively collected photographs of the specimens were assessed twice by six colorectal surgeons to determine the intra-rater and inter-rater accuracy of the German classification and a modification assessing extended right-sided resections. RESULTS: Specimens from 613 resections for right-sided colon cancer were reviewed. Twenty-one specimens were found to be non-assessable, leaving 436 right hemicolectomies, 139 extended right hemicolectomies and 17 right-sided subtotal colectomies. Intra-rater reliability was 0.57-0.74 and weighted kappa coefficients 0.58-0.74, without differences between subgroups. The percentage of agreement between all six participants was 20.3% for all specimens, 21.1% for right hemicolectomy specimens and 18.1% for extended hemicolectomy and right-sided subtotal colectomy specimens. For the right hemicolectomy specimens, the model-based kappa coefficient for agreement was 0.27 (95% CI 0.24-0.30) and for association 0.45 (95% CI 0.41-0.49). CONCLUSION: The German classification of right hemicolectomy specimens showed low intra-rater reliability and inter-rater agreement and association. The use of this classification for scientific purposes appeared not to be reliable.

Association between plane of mesocolic dissection and recurrence after complete mesocolic excision for right-sided colon cancer: a cohort study.

AIM: Dissection in the mesocolic plane is considered by some medical professionals to be crucial in complete mesocolic excision. We aimed to assess whether intramesocolic plane dissection is associated with a risk of recurrence after complete mesocolic excision for right-sided colon cancer. METHOD: This is a single-centre study based on prospectively registered data on patients undergoing resection for Union for International Cancer Control Stage I-III right-sided colon adenocarcinoma during the period 2010-2017. Patients were stratified in an intramesocolic plane group or a mesocolic plane group based on a prospective assessment of fresh specimens by a pathologist. Primary outcome was the 4.2 year risk of recurrence after inverse probability treatment weighting and competing risk analyses. RESULTS: Of 383 patients, 4 (1%) were excluded as the specimen was assessed as muscularis propria plane, 347 (91.6%) specimens were deemed as mesocolic and 32 (8.4%) as intramesocolic. The 4.2 year cumulative incidence of recurrence after inverse probability treatment weighting was 9.1% (95% CI 6.0%-12.1%) in the mesocolic group compared with 14.0% (3.6%-24.5%) in the intramesocolic group with an absolute risk difference in favour of mesocolic plane dissection of 4.9% (-5.7 to 15.6, p = 0.37). No difference was observed in the risk of local recurrence, death before recurrence or overall survival after 4.2 years between the two groups. CONCLUSION: Mesocolic plane dissection can be achieved in more than 90% of patients. The classification seems to be a guide for good surgical practice and not to be used for research purposes.

Plane of mesocolic dissection as predictor of recurrence after complete mesocolic excision for sigmoid colon cancer: A cohort study.

AIM: To investigate whether intramesocolic plane dissection assessed on fresh specimens by the pathologist is a risk factor for recurrence after complete mesocolic excision for sigmoid cancer when compared with mesocolic plane dissection. METHOD: Single-centre study based on prospectively registered data on patients undergoing resection for UICC stage I-III sigmoid colon adenocarcinoma during the period 2010-2017. The patients were stratified into either an intramesocolic plane group or a mesocolic plane group. Primary outcome was risk of recurrence after 4.2 years using inverse probability treatment weighting and competing risk analyses. RESULTS: Of a total of 332 patients, two were excluded as the specimen was assessed as muscularis propria plane, 237 (72%) specimens were deemed as mesocolic and 93 (28%) as intramesocolic. The 4.2-year cumulative incidence of recurrence after inverse probability treatment weighting was 14.9% (10.4-19.3) in the mesocolic group compared with 9.4% (3.7-15.0) in the intramesocolic group, thus the absolute risk difference between the mesocolic plane and intramesocolic plane was 5.5% (-12.5-1.6; p = 0.13) in favour of the intramesocolic group. CONCLUSION: Intramesocolic plane dissection was not a risk factor for recurrence after complete mesocolic excision for sigmoid cancer when compared with mesocolic plane dissection. No difference in risk of local recurrence, death before recurrence, and in overall survival after 4.2 years was observed between the two groups. With less than 1% of the specimens deemed as muscularis propria plane dissection, the classification appears unusable for the risk prediction of sigmoid colon cancer.

Nonmicroradical Resection Margin as a Predictor of Recurrence in Patients With Stage III Colon Cancer Undergoing Complete Mesocolic Excision: A Prospective Cohort Study.

BACKGROUND: The prognostic value of the present definition of microradicality in colon cancer is poorly understood, especially considering the vast influence it has in rectal cancer prognosis. OBJECTIVE: This study aimed to investigate whether the risk of recurrence after complete mesocolic excision for stage III colon cancer is associated with the distance from tumor tissue to resection margin and whether the location of the involved margin is of any significance. DESIGN: A prospective cohort of patients was stratified into 2 groups to distinguish between direct margin invasion (0-mm resection margin) and a ≤1-mm resection margin without direct invasion or 3 groups to distinguish between the location of margin involvement (lateral tumor resection margin, central vascular ligation margin, and nonperitonealized mesocolic resection margin). Patients with microradical resections were used as a control group. SETTINGS: We included all patients undergoing elective complete mesocolic excision for International Union Against Cancer stage III colon cancer at Nordsjællands Hospital between January 1, 2008, and December 31, 2016. PATIENTS: A total of 276 patients met all inclusion criteria and none of the exclusion criteria. MAIN OUTCOME MEASURES: Primary outcome was risk of recurrence after 3.2 years. RESULTS: A total of 41 patients (15%) had a nonmicroradical resection. The 3.2-year cumulative incidence of recurrence for a 0-mm margin was 43% and 24% for a ≤1-mm margin without direct invasion, corresponding with an HR of 4.3 (p = 0.0146) and 1.3 (p = 0.474). The location of the involved margin showed no significant differences. LIMITATIONS: This was a single-center study containing a limited number of patients with a nonmicroradical resection with a risk of type II error. CONCLUSIONS: We found no increased risk of recurrence for a ≤1-mm margin without direct invasion, indicating that the present classification of microradicality might not be justified if an intact posterior mesocolic fascia without invasion of tumor tissue is present. See Video Abstract at http://links.lww.com/DCR/B625. MARGEN DE RESECCIN NO MICRORRADICAL COMO PREDICTOR DE RECURRENCIA EN PACIENTES CON CNCER DE COLON EN ESTADIO III SOMETIDOS A ESCISIN MESOCLICA COMPLETA UN ESTUDIO DE COHORTE PROSPECTIVO: ANTECEDENTES:El valor pronóstico de la definición actual de microrradicalidad en el cáncer de colon es poco conocido, especialmente considerando la gran influencia que tiene en el pronóstico del cáncer de recto.OBJETIVO:Este estudio tiene como objetivo investigar si el riesgo de recurrencia después de la escisión mesocólica completa (CME) para el cáncer de colon en estadio III está asociado con la distancia desde el tejido tumoral hasta el margen de resección y si la localización del margen afectado tiene alguna importancia.DISEÑO:Una cohorte prospectiva de pacientes se estratificó en dos grupos para distinguir entre la invasión del margen directo (margen de resección de 0 mm) y un margen de resección ≤1 mm sin invasión directa, o tres grupos para distinguir entre la localización de la afectación del margen (resección lateral del margen del tumor, margen de ligadura vascular central y margen de resección mesocólica no peritonizada). Los pacientes con resecciones microrradicales se utilizaron como grupo control.ENTORNO CLÍNICO:Incluimos a todos los pacientes sometidos a CME electiva por cáncer de colon en estadio III de la UICC en el Hospital Nordsjællands, Dinamarca, entre el 1 de enero de 2008 y el 31 de diciembre de 2016.PACIENTES:Un total de 276 pacientes cumplieron todos los criterios de inclusión y ninguno de los criterios de exclusión.PRINCIPALES MEDIDAS DE RESULTADO:El resultado primario fue el riesgo de recurrencia después de 3 · 2 años.RESULTADOS:Un total de 41 (15%) pacientes tuvieron una resección no microrradical. La incidencia acumulada de recurrencia a los 3,2 años para un margen de 0 mm fue del 43% y del 24% para un margen ≤1 mm sin invasión directa, lo que corresponde a un cociente de riesgo de 4,3 (p = 0,0146) y 1,3 (p = 0,474) respectivamente. La localización del margen afectado no mostró diferencias significativas.LIMITACIONES:Estudio unicéntrico con un número limitado de pacientes con resección no microrradical con riesgo de error tipo II.CONCLUSIONES:No encontramos un mayor riesgo de recurrencia para un margen ≤1 mm sin invasión directa, lo que indica que la clasificación actual de microrradicalidad podría no estar justificada si está presente una fascia mesocólica posterior intacta sin invasión del tejido tumoral. Consulte Video Resumen en http://links.lww.com/DCR/B625. (Traducción-Dr Yazmin Berrones-Medina).

Accuracy of preoperative staging with multidetector computed tomography in colon cancer.

AIM: Multidetector computed tomography (MDCT) is the main preoperative decision-making tool in colon cancer treatment, thus the validation of daily clinical practice is warranted. The only published study validating the accuracy of MDCT in a national cohort was performed more than a decade ago. With neoadjuvant chemotherapy for patients with preoperatively assessed locally advanced cancer and the emergence of other personalized treatments we aimed to validate the accuracy of MDCT in a national cohort. METHOD: The study is based on the Danish Colorectal Cancer Group (DCCG) database and included all Danish patients diagnosed with primary colon adenocarcinoma between January 2015 and December 2018. The primary study outcome was the accuracy of MDCT in identifying patients with locally advanced disease. The secondary outcomes were the accuracy of predicting UICC Stage I based on predicting the tumour category (pT3-T4 versus pT1-T2) and lymph node metastasis. RESULTS: A total 3465 patients were included in the analyses regarding locally advanced colon cancer. The sensitivity and specificity were 0.61 (0.58-0.64) and 0.85 (0.83-0.86), respectively, for CT to predict locally advanced disease. The sensitivity and specificity were 0.63 (0.59-0.66) and 0.80 (0.78-0.81), respectively, for predicting UICC Stage I in 4496 patients. Thirty six per cent of the patients assessed as having locally advanced disease and 58% assessed as Stage I were misclassified by MDCT. CONCLUSION: The present standard in Denmark questions whether the implementation of personalized medicine such as neoadjuvant adjuvant chemotherapy and tailor-made resections based on MDCT is justified.