Dissociation of EphB2 signaling pathways mediating progenitor cell proliferation and tumor suppression.

Signaling proteins driving the proliferation of stem and progenitor cells are often encoded by proto-oncogenes. EphB receptors represent a rare exception; they promote cell proliferation in the intestinal epithelium and function as tumor suppressors by controlling cell migration and inhibiting invasive growth. We show that cell migration and proliferation are controlled independently by the receptor EphB2. EphB2 regulated cell positioning is kinase-independent and mediated via phosphatidylinositol 3-kinase, whereas EphB2 tyrosine kinase activity regulates cell proliferation through an Abl-cyclin D1 pathway. Cyclin D1 regulation becomes uncoupled from EphB signaling during the progression from adenoma to colon carcinoma in humans, allowing continued proliferation with invasive growth. The dissociation of EphB2 signaling pathways enables the selective inhibition of the mitogenic effect without affecting the tumor suppressor function and identifies a pharmacological strategy to suppress adenoma growth.

Standardization of the Definition and Surgical Management of Splenic Flexure Carcinoma by an International Expert Consensus Using the Delphi Technique: Room for Improvement?

BACKGROUND: Surgical management of splenic flexure carcinoma remains controversial. OBJECTIVE: This study aimed to establish an expert international consensus on splenic flexure carcinoma management. DESIGN: A 3-round online-based Delphi study was conducted between September 2020 and April 2021. SETTING: The first round included 18 experts from 12 different countries. For the second and third rounds, each expert in the first round was asked to invite 2 more colorectal surgeons (n = 47). Out of 47 invited experts, 89% (n = 42) participated in the second and third rounds of the consensus. INTERVENTIONS: A total of 35 questions were created and sent via the online questionnaire tool. MAIN OUTCOME MEASURES: Levels of recommendation based on voting concordance were graded as follows: more than 75% agreement was defined as strong, between 50% and 75% as moderate, and below 50% as weak. RESULTS: There was moderate consensus on the definition of splenic flexure (55%) as 10 cm from either side where the distal transverse colon turns into the proximal descending colon. Also, experts recommended an abdominopelvic CT scan plus intraoperative exploration (moderate consensus, 72%) for tumor localization and cancer registry. Segmental colectomy was the preferred technique for the management of splenic flexure carcinoma in the elective setting (72%). Moderate consensus was achieved on the technique of complete mesocolic excision and central vascular ligation principles for splenic flexure carcinoma (74%). Only strong consensus was achieved on the surgical approach for minimally invasive surgery (88%). LIMITATIONS: Subjective decisions are based on individual expert clinical experience and not evidence based. CONCLUSIONS: This is the first internationally conducted Delphi consensus study regarding splenic flexure carcinoma. The definition of splenic flexure remains ambiguous. To more effectively compare oncologic outcomes among different cancer registries, guidelines need to be developed to standardize each domain and avoid arbitrary definitions. See Video Abstract at http://links.lww.com/DCR/C143 . ESTANDARIZACIN DE LA DEFINICIN Y MANEJO QUIRRGICO DEL CARCINOMA DE NGULO ESPLNICO ESTABLECIDO POR UN CONSENSO INTERNACIONAL DE EXPERTOS UTILIZANDO LA TCNICA DELPHI ESPACIO PARA MEJORAR: ANTECEDENTES:El tratamiento quirúrgico del cáncer de ángulo esplénico sigue siendo controvertido.OBJETIVO:Establecer un consenso internacional de expertos sobre el manejo del cáncer del ángulo esplénico.DISEÑO:Se condujo un estudio Delphi en línea de 3 rondas entre septiembre de 2020 y febrero de 2021.ESCENARIO:La primera ronda incluyó a 18 expertos de 12 países distintos. Para la segunda y tercera rondas, a cada experto de la primera ronda se le pidió que invitara a 2 cirujanos colorrectales más de su región (n = 47). De los 47 expertos invitados, el 89% (n = 42) participó en la segunda y tercera ronda del consenso.INTERVENCIONES:Se crearon y enviaron un total de 35 preguntas a través de la herramienta de cuestionario en línea.PRINCIPALES MEDIDAS DE RESULTADO:Los niveles de recomendación basados en la concordancia de votos fueron jerarquizados de la siguiente manera: más del 75% de acuerdo se definió como fuerte, entre 50 y 75% como moderado y por debajo del 50% como débil.RESULTADOS:Hubo un consenso moderado sobre la definición de ángulo esplénico (55%) como 10 cm desde cualquier lado donde el colon transverso distal se convierte en el colon descendente proximal. Así también, los expertos recomendaron la tomografía computarizada abdominopélvica más la exploración intraoperatoria (consenso moderado, 72%) para la localización del tumor y el registro del ángulo esplénico. La colectomía segmentaria fue la técnica preferida para el tratamiento del cáncer de ángulo esplénico en el caso de ser electivo (72%). Se logró un consenso moderado sobre la técnica de escisión completa del mesocolon y los principios de ligadura vascular a nivel central para el cáncer de ángulo esplénico (74%). Solo se logró un fuerte consenso sobre el abordaje quirúrgico para la cirugía mínimamente invasiva (88%).LIMITACIONES:Decisiones subjetivas basadas en la experiencia clínica de expertos individuales y no basadas en evidencia.CONCLUSIONES:Este es el primer estudio internacional de consenso Delphi realizado sobre el cáncer de ángulo esplénico. Si bien encontramos un consenso moderado sobre las modalidades de diagnóstico preoperatorio y el manejo quirúrgico, la definición de ángulo esplénico sigue siendo ambigua. Para comparar de manera más efectiva los resultados oncológicos entre diferentes registros de cáncer, se deben desarrollar pautas para estandarizar cada dominio y evitar definiciones arbitrarias. Consulte Video Resumen en http://links.lww.com/DCR/C143 . (Traducción-Dr. Osvaldo Gauto ).

Locally recurrent rectal cancer: oncological outcomes with different treatment strategies in two tertiary referral units.

BACKGROUND: The optimal treatment for patients with locally recurrent rectal cancer (LRRC) is controversial. The aim of this study was to investigate different treatment strategies in two leading tertiary referral hospitals in Europe. METHODS: All patients who underwent curative surgery for LRRC between January 2003 and December 2017 in Catharina Hospital, Eindhoven, the Netherlands (CHE), or Karolinska University Hospital, Stockholm, Sweden (KAR), were studied retrospectively. Available MRIs were reviewed to obtain a uniform staging for optimal comparison of both cohorts. The main outcomes studied were overall survival (OS), local re-recurrence-free survival (LRFS), and metastasis-free survival (MFS). RESULTS: In total, 377 patients were included, of whom 126 and 251 patients came from KAR and CHE respectively. At 5 years, the LRFS rate was 62.3 per cent in KAR versus 42.3 per cent in CHE (P = 0.017), whereas OS and MFS were similar. A clear surgical resection margin (R0) was the strongest prognostic factor for survival, with a hazard ratio of 2.23 (95 per cent c.i. 1.74 to 2.86; P < 0.001), 3.96 (2.87 to 5.47; P < 0.001), and 2.00 (1.48 to 2.69; P < 0.001) for OS, LRFS, and MFS respectively. KAR performed more extensive operations, resulting in more R0 resections than in CHE (76.2 versus 61.4 per cent; P = 0.004), whereas CHE relied more on neoadjuvant treatment and intraoperative radiotherapy, to reduce the morbidity of multivisceral resections (P < 0.001). CONCLUSION: In radiotherapy-naive patients, neoadjuvant full-course chemoradiation confers the best oncological outcome. However, neoadjuvant therapy does not diminish the need for extended radical surgery to increase R0 resection rates.

Oncological outcomes after complete mesocolic excision in right-sided colon cancer: a population-based study.

AIM: Complete mesocolic excision (CME) has been proposed as the preferred surgical technique for resection of colon cancer. This prospective cohort study evaluates the effect of CME surgery on colon cancer mortality after right-sided hemicolectomy on a population level. METHODS: Data from the Swedish Colorectal Cancer Registry and the Cause of Death Registry on all patients treated with elective right-sided hemicolectomy for colon cancer Stages I-III in the Stockholm County 2008-2012 were analysed. Adherence to principles of CME surgery was determined by structured analysis of anonymized surgical reports regarding the presence of five essential features. The exposure to CME was graded as group 0 (not exposed to CME), group 1 (intermediate) and group 2 (exposed to CME). RESULTS: In total, 1171 patients were analysed with 234 (20.0%) patients in CME group 0, 453 (38.7%) patients in CME group 1 and 484 (41.3%) in CME group 2. The 5-year colon cancer mortality was 20.2% in CME group 0, 13.9% in CME group 1 and 13.1% in CME group 2 (P = 0.026). The adjusted hazard ratio for colon cancer mortality was 0.61 (95% CI 0.42-0.91; P = 0.014) for CME group 1 and 0.52 (95% CI 0.35-0.77; P = 0.001) for CME group 2. DISCUSSION: The presence of predefined CME features in surgical reports was related to a graded benefit on cancer-specific mortality after right-sided hemicolectomy for colon cancer Stages I-III.

Emergency resection or diverting stoma followed by elective resection in patients with colonic obstruction due to locally advanced cancer: a national cohort study.

AIM: The aim was to assess long-term prognosis after emergency resection versus primary diverting stoma followed by elective tumour resection. METHOD: A national-register-based cohort study with retrospective analysis of prospectively collected data was performed. All Swedish patients with non-metastatic obstructive locally advanced colon cancer treated with emergency resection or diverting stoma, followed by an elective resection, between 2007 and 2017 were included. The Kaplan-Meier method and Cox proportional hazards model were used to compare all-cause mortality between patients with emergency resection and elective right- and left-sided resection. The multivariable model was adjusted for year of diagnosis, age at diagnosis, sex, Charlson Comorbidity Index, American Society of Anesthesiologists class, tumour location and pN stage. RESULTS: In all, 751 patients with a tumour in the right colon and 700 patients with a tumour in the left colon were included. Emergency resection was more common in patients with right-sided colon tumours (681/751) than in patients with left-sided colon tumours (483/700). The 5-year overall survival in patients with right-sided tumours was 25% after emergency resection and 46% after diverting stoma followed by elective resection (log-rank test P = 0.001). The corresponding numbers for patients with left-sided colon tumours were 40% and 64% (P < 0.001). Emergency resection was independently associated with increased all-cause mortality in patients with left-sided tumour (hazard ratio 1.63, 95% CI 1.21-2.19) but not in patients with right-sided tumour (hazard ratio 1.21, 95% CI 0.80-1.81). CONCLUSION: Diverting stoma followed by elective resection is associated with improved survival compared with emergency resection in patients with left-sided colonic obstruction due to locally advanced tumours.

Definition of the Rectum: An International, Expert-based Delphi Consensus.

BACKGROUND: The wide global variation in the definition of the rectum has led to significant inconsistencies in trial recruitment, clinical management, and outcomes. Surgical technique and use of preoperative treatment for a cancer of the rectum and sigmoid colon are radically different and dependent on the local definitions employed by the clinical team. A consensus definition of the rectum is needed to standardise treatment. METHODS: The consensus was conducted using the Delphi technique with multidisciplinary colorectal experts from October, 2017 to April, 2018. RESULTS: Eleven different definitions for the rectum were used by participants in the consensus. Magnetic resonance imaging (MRI) was the most frequent modality used to define the rectum (67%), and the preferred modality for 72% of participants. The most agreed consensus landmark (56%) was "the sigmoid take-off," an anatomic, image-based definition of the junction of the mesorectum and mesocolon. In the second round, 81% of participants agreed that the sigmoid take-off as seen on computed tomography or MRI achieved consensus, and that it could be implemented in their institution. Also, 87% were satisfied with the sigmoid take-off as the consensus landmark. CONCLUSION: An international consensus definition for the rectum is the point of the sigmoid take-off as visualized on imaging. The sigmoid take-off can be identified as the mesocolon elongates as the ventral and horizontal course of the sigmoid on axial and sagittal views respectively on cross-sectional imaging. Routine application of this landmark during multidisciplinary team discussion for all patients will enable greater consistency in tumour localisation.

An image fusion tool for echo-guided left ventricular lead placement in cardiac resynchronization therapy: Performance and workflow integration analysis.

BACKGROUND: The response rate to cardiac resynchronization therapy (CRT) may be improved if echocardiographic-derived parameters are used to guide the left ventricular (LV) lead deployment. Tools to visually integrate deformation imaging and fluoroscopy to take advantage of the combined information are lacking. METHODS: An image fusion tool for echo-guided LV lead placement in CRT was developed. A personalized average 3D cardiac model aided visualization of patient-specific LV function in fluoroscopy. A set of coronary venography-derived landmarks facilitated registration of the 3D model with fluoroscopy into a single multimodality image. The fusion was both performed and analyzed retrospectively in 30 cases. Baseline time-to-peak values from echocardiography speckle-tracking radial strain traces were color-coded onto the fused LV. LV segments with suspected scar tissue were excluded by cardiac magnetic resonance imaging. The postoperative augmented image was used to investigate: (a) registration accuracy and (b) agreement between LV pacing lead location, echo-defined target segments, and CRT response. RESULTS: Registration time (264 ± 25 seconds) and accuracy (4.3 ± 2.3 mm) were found clinically acceptable. A good agreement between pacing location and echo-suggested segments was found in 20 (out of 21) CRT responders. Perioperative integration of the proposed workflow was successfully tested in 2 patients. No additional radiation, compared with the existing workflow, was required. CONCLUSIONS: The fusion tool facilitates understanding of the spatial relationship between the coronary veins and the LV function and may help targeted LV lead delivery.

Risk of Acute Testicular Failure After Preoperative Radiotherapy for Rectal Cancer: A Prospective Cohort Study.

OBJECTIVE: The aim of this study was to assess the acute effect of preoperative RT for rectal cancer on endocrine testicular function. BACKGROUND: Preoperative radiotherapy (RT) enhances local control and cancer-specific survival in patients treated for rectal cancer. In case series, a negative acute effect on Leydig cell function has been reported. METHODS: This prospective cohort study included 168 males with rectal or prostate cancer stage I-III. Males treated with preoperative RT and surgery for rectal cancer formed the exposed group (n = 93). Males treated with surgery alone were assigned to the unexposed group (n = 75). The androgen levels were assessed at baseline and after preoperative RT. The exposure was quantified with the treatment planning system to estimate the cumulative testicular dose (TD). The risk of low T (serum T < below 8 nmol/L) was the primary endpoint. Secondary endpoints were serum testosterone (T), bioavailable T, luteinizing hormone (LH), and the LH-T ratio. RESULTS: The baseline levels of androgens were not related to exposure status or type of cancer. The proportion of low T increased from 14.6% at baseline to 35.4% after RT, relative risk 2.41 (95% CI 1.57 to 3.71, P < 0.001). Preoperative RT resulted in a significant decrease of serum and bioavailable T and a significant increase of LH and LH-T ratio. The decline in serum and bioavailable T was related to the TD. CONCLUSIONS: Preoperative RT for rectal cancer results in dose-dependent primary testicular failure increasing the risk of hypogonadism at the time of surgery by 2.4 times (number needed to harm = 5).

Management and Outcome After Multivisceral Resections in Patients with Locally Advanced Primary Colon Cancer.

BACKGROUND: Locally advanced colon cancer invading surrounding organs or structures is challenging to surgeons and oncologists. Multivisceral resections with tumor removal en bloc with invaded tissues provide the best chance for cure. OBJECTIVE: We aimed to assess the management and outcomes after multivisceral resections in patients with clinically infiltrative, locally advanced primary colon cancer. DESIGN: This is a descriptive retrospective cohort study. SETTINGS: A total of 121 consecutive patients with locally advanced primary colon cancer underwent en bloc multivisceral resections at a tertiary referral unit for colorectal cancer between 2007 and 2014. MAIN OUTCOME MEASURES: Patient demographics, surgical details, histopathological findings, and outcomes were analyzed through registry data and reviews of patient files. RESULTS: An R0 resection was achieved in 112 patients (92.6%), and an R1 resection was achieved in 9 patients (7.4%). Actual tumor cell infiltration in resected tissues was found in 77 patients (63.6%), and inflammation was found in 44 patients (36.4%). The estimated 5-year overall survival was 60.8% and 86.9%. Survival was significantly better after R0 than after R1 resections. After a median follow-up of 28 months, recurrent disease was diagnosed in 25 patients (20.7%). Female sex, low tumor stage, and adjuvant chemotherapy, but not tumor infiltration per se, were independently associated with better overall survival in a multivariate analysis. LIMITATIONS: The main limitations of the study are the retrospective design and the fact that all patients were operated on at 1 institution by a small number of surgeons. CONCLUSIONS: Patients with locally advanced colon cancer can be cured with an R0 resection. All involved surrounding tissues should be removed en bloc with the primary tumor. See Video Abstract at http://links.lww.com/DCR/A548.

Are Colon and Rectal Cancer Two Different Tumor Entities? A Proposal to Abandon the Term Colorectal Cancer.

Colon cancer (CC) and rectal cancer (RC) are synonymously called colorectal cancer (CRC). Based on our experience in basic and clinical research as well as routine work in the field, the term CRC should be abandoned. We analyzed the available data from the literature and results from our multicenter Research Group Oncology of Gastrointestinal Tumors termed FOGT to confirm or reject this hypothesis. Anatomically, the risk of developing RC is four times higher than CC, while physical activity helps to prevent CC but not RC. Obvious differences exist in molecular carcinogenesis, pathology, surgical topography and procedures, and multimodal treatment. Therefore, we conclude that CC is not the same as RC. The term "CRC" should no longer be used as a single entity in basic and clinical research as well as other areas of classification.

Optimal fractionation of preoperative radiotherapy and timing to surgery for rectal cancer (Stockholm III): a multicentre, randomised, non-blinded, phase 3, non-inferiority trial.

BACKGROUND: Radiotherapy reduces the risk of local recurrence in rectal cancer. However, the optimal radiotherapy fractionation and interval between radiotherapy and surgery is still under debate. We aimed to study recurrence in patients randomised between three different radiotherapy regimens with respect to fractionation and time to surgery. METHODS: In this multicentre, randomised, non-blinded, phase 3, non-inferiority trial (Stockholm III), all patients with a biopsy-proven adenocarcinoma of the rectum, without signs of non-resectability or distant metastases, without severe cardiovascular comorbidity, and planned for an abdominal resection from 18 Swedish hospitals were eligible. Participants were randomly assigned with permuted blocks, stratified by participating centre, to receive either 5 × 5 Gy radiation dose with surgery within 1 week (short-course radiotherapy) or after 4-8 weeks (short-course radiotherapy with delay) or 25 × 2 Gy radiation dose with surgery after 4-8 weeks (long-course radiotherapy with delay). After a protocol amendment, randomisation could include all three treatments or just the two short-course radiotherapy treatments, per hospital preference. The primary endpoint was time to local recurrence calculated from the date of randomisation to the date of local recurrence. Comparisons between treatment groups were deemed non-inferior if the upper limit of a double-sided 90% CI for the hazard ratio (HR) did not exceed 1·7. Patients were analysed according to intention to treat for all endpoints. This study is registered with ClinicalTrials.gov, number NCT00904813. FINDINGS: Between Oct 5, 1998, and Jan 31, 2013, 840 patients were recruited and randomised; 385 patients in the three-arm randomisation, of whom 129 patients were randomly assigned to short-course radiotherapy, 128 to short-course radiotherapy with delay, and 128 to long-course radiotherapy with delay, and 455 patients in the two-arm randomisation, of whom 228 were randomly assigned to short-course radiotherapy and 227 to short-course radiotherapy with delay. In patients with any local recurrence, median time from date of randomisation to local recurrence in the pooled short-course radiotherapy comparison was 33·4 months (range 18·2-62·2) in the short-course radiotherapy group and 19·3 months (8·5-39·5) in the short-course radiotherapy with delay group. Median time to local recurrence in the long-course radiotherapy with delay group was 33·3 months (range 17·8-114·3). Cumulative incidence of local recurrence in the whole trial was eight of 357 patients who received short-course radiotherapy, ten of 355 who received short-course radiotherapy with delay, and seven of 128 who received long-course radiotherapy (HR vs short-course radiotherapy: short-course radiotherapy with delay 1·44 [95% CI 0·41-5·11]; long-course radiotherapy with delay 2·24 [0·71-7·10]; p=0·48; both deemed non-inferior). Acute radiation-induced toxicity was recorded in one patient (<1%) of 357 after short-course radiotherapy, 23 (7%) of 355 after short-course radiotherapy with delay, and six (5%) of 128 patients after long-course radiotherapy with delay. Frequency of postoperative complications was similar between all arms when the three-arm randomisation was analysed (65 [50%] of 129 patients in the short-course radiotherapy group; 48 [38%] of 128 patients in the short-course radiotherapy with delay group; 50 [39%] of 128 patients in the long-course radiotherapy with delay group; odds ratio [OR] vs short-course radiotherapy: short-course radiotherapy with delay 0·59 [95% CI 0·36-0·97], long-course radiotherapy with delay 0·63 [0·38-1·04], p=0·075). However, in a pooled analysis of the two short-course radiotherapy regimens, the risk of postoperative complications was significantly lower after short-course radiotherapy with delay than after short-course radiotherapy (144 [53%] of 355 vs 188 [41%] of 357; OR 0·61 [95% CI 0·45-0·83] p=0·001). INTERPRETATION: Delaying surgery after short-course radiotherapy gives similar oncological results compared with short-course radiotherapy with immediate surgery. Long-course radiotherapy with delay is similar to both short-course radiotherapy regimens, but prolongs the treatment time substantially. Although radiation-induced toxicity was seen after short-course radiotherapy with delay, postoperative complications were significantly reduced compared with short-course radiotherapy. Based on these findings, we suggest that short-course radiotherapy with delay to surgery is a useful alternative to conventional short-course radiotherapy with immediate surgery. FUNDING: Swedish Research Council, Swedish Cancer Society, Stockholm Cancer Society, and the Regional Agreement on Medical Training and Clinical Research in Stockholm.

Abdominoperineal Excision: Technical Challenges in Optimal Surgical and Oncological Outcomes after Abdominoperineal Excision for Rectal Cancer.

Treatment results in rectal cancer have improved significantly during the recent two decades, but local control and survival after abdominoperineal excision (APE) have not improved to the same degree as that seen after anterior resection (AR). The reason for this is an increased risk of inadvertent bowel perforations and tumor involved margins after APE as compared with AR. The conventional synchronous combined APE has not been a standardized procedure and consequently oncological outcomes have varied considerably between different institutions and in different reports. With the new concept of APE, based on well-defined anatomical structures, the procedure can be categorized as intersphincteric APE, extralevator APE, and ischioanal APE. This article discusses the technical aspects and results from this approach.

Assessment of testicular dose during preoperative radiotherapy for rectal cancer.

BACKGROUND: Radiotherapy (RT) for rectal cancer can have adverse effects on testicular function resulting in azoospermia and low testosterone levels. Variability of testicular dose (TD) due to differences in position of testes has been assessed with scrotal dosimeters and resulted in substantial variability of delivered TD. The aim of this study was to estimate planned and delivered TD using a treatment planning system (TPS). METHODS: In 101 men treated with RT for rectal cancer the cumulative mean TD (mTD) was calculated by TPS based on plan-computed tomography (CT) to evaluate the effect of different predictors on planned TD. The delivered TD was estimated by TPS based on repeated cone-beam CTs in 32 of 101 men to assess within-person variability of planned and delivered TD in a longitudinal analysis. RESULTS: The median planned mTD for short course RT was 0.57 Gy (range 0.06-14.37 Gy) and 0.81 Gy (range 0.36-10.80 Gy) for long course RT. The median planned mTD was similar to the median delivered mTD in the 32 men analysed over the entire course of RT (p=0.84). The mTD did not change significantly over time of planning and delivering RT. The variation in proximity between testes and planning target volume (PTV) was related to within-person variability of mTD in men on the 50th and 75th percentile of mTD and as expected the absolute difference between planned and delivered mTD increased with higher mTD. CONCLUSION: Testicular doses calculated based on plan-CT are an accurate estimation of delivered TD based on repeated cone beam (CB)CT. The within-person variability of TD is related to variation in proximity between testes and PTV in men with moderate to high TD.

Testosterone and body composition in men after treatment for rectal cancer.

INTRODUCTION: Preoperative radiotherapy for rectal cancer may affect Leydig cell function. However, the diagnosis of posttreatment hypogonadism is complicated as sexual symptoms associated to hypogonadism can rely on adverse events of pelvic radiation and surgery. AIM: The objective of this study was to investigate the association of testosterone levels and body composition. The clinical value of such an association is tested subsequently in the study population. METHODS: This was a longitudinal study with prospective registration during 2010-2012 and 1-year follow up. Men with rectal cancer stage I-III, treated with radiotherapy and surgery, were eligible, and 40 of 53 men were available for analysis. MAIN OUTCOME MEASURES: The areas of skeletal muscle and adipose tissue were assessed on a defined section of a computed tomography at baseline and after 1 year. Androgen levels were recorded from morning blood samples. RESULTS: The area of skeletal muscle was related to the level of bioavailable testosterone (P = 0.01) but not to the level of serum testosterone (P = 0.36). The subcutaneous adipose tissue was not related to testosterone levels. Men with posttreatment serum testosterone levels of 8-12 nmol/L and longitudinal loss of psoas muscle area had a significantly increased luteinizing hormone-testosterone ratio compared with those with longitudinal gain of psoas muscle. CONCLUSIONS: The area of psoas muscle is related to the unbound fraction of circulating testosterone in men treated for rectal cancer. The longitudinal loss of psoas muscle in men with borderline levels of serum testosterone seems to be an androgen-related symptom associated with compensatory activation of the pituitary-gonadal axis indicating a testicular failure in this group of patients.

Ultra low resection versus abdomino-perineal excision in low rectal cancer.

There have been several important improvements in the management of patients with rectal cancer during the recent 20 years. For more accurate local and distant tumour staging, introduction of neoadjuvant treatments, improved surgery, a more precise macroscopic and microscopic evaluation of the specimen and MDT discussions have all been crucial in improving local control and survival. However, the most important factor has been the TME technique with standardisation of the surgical procedure. For patients with low rectal cancer, the decision making is complex with several treatment options, including the choice between neoadjuvant treatment followed by surgery or surgery alone, restorative procedures or APE. If an APE is necessary, this must also be tailored to the individual patient based on patient's characteristics and the extent of local tumour growth.

Potentials of high resolution magnetic resonance imaging versus computed tomography for preoperative local staging of colon cancer.

BACKGROUND: Preoperative identification of locally advanced colon cancer is of importance in order to properly plan treatment. PURPOSE: To study high resolution T2-weighted magnetic resonance imaging (MRI) versus computed tomography (CT) for preoperative staging of colon cancer with surgery and histopathology as reference standard. MATERIAL AND METHODS: Twenty-eight patients with a total of 29 tumors were included. Patients were examined on a 1.5 T MR unit using a phased array body coil. T2 turbo spin-echo high resolution sequences were obtained in a coronal, transverse, and perpendicular plane to the long axis of the colon at the site of the tumor. Contrast-enhanced CT was performed using a protocol for metastasis staging. The examinations were independently evaluated by two gastrointestinal radiologists using criteria adapted to imaging for prediction of T-stage, N-stage, and extramural venous invasion. Based on the T-stage, tumors were divided in to locally advanced (T3cd-T4) and not locally advanced (T1-T3ab). Surgical and histopathological findings served as reference standard. RESULTS: Using MRI, T-stage, N-stage, and extramural venous invasion were correctly predicted for each observer in 90% and 93%, 72% and 69%, and 82% and 78% of cases, respectively. With CT the corresponding results were 79% and 76%, 72% and 72%, 78% and 67%. For MRI inter-observer agreements (Kappa statistics) were 0.79, 0.10, and 0.76. For CT the corresponding results were 0.64, 0.66, and 0.22. CONCLUSION: Patients with locally advanced colon cancer, defined as tumor stage T3cd-T4, can be identified by both high resolution MRI and CT, even when CT is performed with a metastasis staging protocol. MRI may have an advantage, due to its high soft tissue discrimination, to identify certain prognostic factors such as T-stage and extramural venous invasion.

Determinants of the time-to-peak left ventricular dP/dt (Td) and QRS duration with different fusion strategies in cardiac resynchronization therapy.

Background: Cardiac resynchronization therapy (CRT) is helpful in selected patients; however, responder rates rarely exceed 70%. Optimization of CRT may therefore benefit a large number of patients. Time-to-peak dP/dt (Td) is a novel marker of myocardial synergy that reflects the degree of myocardial dyssynchrony with the potential to guide and optimize treatment with CRT. Optimal electrical activation is a prerequisite for CRT to be effective. Electrical activation can be altered by changing the electrical wave-front fusion resulting from pacing to optimize resynchronization. We designed this study to understand the acute effects of different electrical wave-front fusion strategies and LV pre-/postexcitation on Td and QRS duration (QRSd). A better understanding of measuring and optimizing resynchronization can help improve the benefits of CRT. Methods: Td and QRSd were measured in 19 patients undergoing a CRT implantation. Two biventricular pacing groups were compared: pacing the left ventricle (LV) with fusion with intrinsic right ventricular activation (FUSION group) and pacing the LV and right ventricle (RV) at short atrioventricular delay (STANDARD group) to avoid fusion with intrinsic RV activation. A quadripolar LV lead enabled pacing from widely separated electrodes; distal (DIST), proximal (PROX) and both electrodes combined (multipoint pacing, MPP). The LV was stimulated relative in time to RV activation (either RV pace-onset or QRS-onset), with the LV stimulated prior to (PRE), simultaneous with (SIM) or after (POST) RV activation. In addition, we analyzed the interactions of the two groups (FUSION/STANDARD) with three different electrode configurations (DIST, PROX, MPP), each paced with three different degrees of LV pre-/postexcitation (PRE, SIM, POST) in a statistical model. Results: We found that FUSION provided shorter Td and QRSd than STANDARD, MPP provided shorter Td and QRSd than DIST and PROX, and SIM provided both the shortest QRSd and Td compared to PRE and POST. The interaction analysis revealed that pacing MPP with fusion with intrinsic RV activation simultaneous with the onset of the QRS complex (MPP*FUSION*SIM) shortened QRSd and Td the most compared to all other modes and configurations. The difference in QRSd and Td from their respective references were significantly correlated (ß = 1, R = 0.9, p < 0.01). Conclusion: Pacing modes and electrode configurations designed to optimize electrical wave-front fusion (intrinsic RV activation, LV multipoint pacing and simultaneous RV and LV activation) shorten QRSd and Td the most. As demonstrated in this study, electrical and mechanical measures of resynchronization are highly correlated. Therefore, Td can potentially serve as a marker for CRT optimization.

Initial magnetic resonance imaging tumour regression grade (mrTRG) as response evaluation after neoadjuvant treatment predicts sustained complete response in patients with rectal cancer.

PURPOSE: Reliable predictors of a sustained clinical complete tumour response (cCR) after neoadjuvant therapy in rectal cancer (RC) are lacking. The aim of this study was to determine if the tumour regression grade (TRG) assessed by magnetic resonance imaging (MRI), at the first restaging after neoadjuvant therapy can predict organ preservation, and to estimate the time interval after which surgery should be recommended in patients who remain in near cCR. MATERIALS AND METHODS: Eighty-three consecutive patients were assessed by MRI as having a cCR (mrTRG 1) or near cCR (mrTRG 2) after neoadjuvant therapy. Cox proportional hazards regression models and Kaplan-Meier survival analyses were used to determine associations between resection-free survival (RFS) and mrTRG at the first restaging, and in relation to mrTRG with a landmark period. mrTRG and pathological findings were compared in operated patients. RESULTS: mrTRG 2 at the first restaging significantly predicted poorer RFS during follow up. The best prediction of RFS was mrTRG at landmark 16 weeks after termination of radiotherapy; 42 out of 49 patients (86%) evaluated as mrTRG 1 had cCR at one year of follow up. In contrast, 12 out of 15 patients (80%) evaluated as mrTRG 2 had clinical signs of tumour and were recommended surgery. CONCLUSIONS: The first mrTRG, and to an even greater extent mrTRG at landmark 16 weeks predicts RFS. Patients who remain mrTRG 2 at 5-6 months after radiotherapy with signs of tumour should be recommended surgery. These findings may help in patient counselling and surgical decision-making.

The impact of hospital volume on survival in patients with locally advanced colonic cancer.

BACKGROUND: High hospital volume has been shown associated with improved survival in patients with several cancers. The aim of this nationwide cohort study was to investigate whether hospital volume affects survival in patients with locally advanced colonic cancer. METHODS: All patients with non-metastatic locally advanced colonic cancer diagnosed between 2007 and 2017 in Sweden were included. Tertiles of annual hospital volume of locally advanced colonic cancer were analysed and 5-year overall and colonic cancer-specific survival were calculated with the Kaplan-Meier method. HRs comparing all-cause and colonic cancer-specific mortality rates were estimated using Cox models adjusted for potential confounders (age, sex, year of diagnosis, co-morbidity, elective/emergency resection, and university hospital) and mediators (preoperative multidisciplinary team assessment, neoadjuvant chemotherapy, radical resection, and surgical experience). RESULTS: A total of 5241 patients were included with a mean follow-up of 2.7-2.8 years for low- and high-volume hospitals. The number of patients older than 79 years were 569 (32.3 per cent), 495 (29.9 per cent), and 482 (26.4 per cent) for low-, medium- and high-volume hospitals respectively. The 3-year overall survival was 68 per cent, 60 per cent and 58 per cent for high-, medium- and low-volume hospitals, respectively (P < 0.001 from log rank test). High volume hospitals were associated with reduced all-cause and colon cancer-specific mortality after adjustments for potential confounders (HR 0.76, 95 per cent CI 0.62 to 0.93 and HR 0.73, 95 per cent CI 0.59 to 0.91, respectively). The effect remained after inclusion of potential mediators. CONCLUSIONS: High hospital volume is associated with reduced mortality in patients with locally advanced colonic cancer.

Vaginal reconstruction using a gluteal transposition flap after abdominoperineal excision for anorectal malignancy.

The purpose of this study is to present and evaluate a surgical method using gluteal flap for combined perineal and vaginal reconstruction after abdominoperineal excision (APE) with partial vaginectomy for anorectal malignancy. The method is a two-centre study of consecutive patients undergoing APE including partial vaginectomy for anorectal tumours, with immediate combined perineal and vaginal reconstruction using gluteal flaps. Follow-up data were retrieved via retrospective review of medical records, questionnaires and gynaecological examinations. Some 34 patients fulfilled the inclusion criteria. At the time of follow-up, 14 (78%) of the 18 patients alive responded to questionnaires. Seven (50%) of the survey responders agreed to undergo gynaecological examination. Major flap-specific complications (Clavien-Dindo > 2) were observed in 3 (9%) patients. Among survey responders, 11 (79%) had been sexually active preoperatively of which five (45%) resumed sexual activity postoperatively and three (27%) resumed vaginal intercourse. These three patients had all implemented an active vaginal health promotion strategy postoperatively. Perineo-vaginal reconstruction using gluteal flap after extended APE for anorectal malignancy is feasible. Although comparable to other methods of reconstruction, the rate of perineo-vaginal complications is high and post-operative sexual dysfunction is substantial. Postoperative strategies for vaginal health promotion may improve sexual function after vaginal reconstruction.