Protocol for the CoNoR Study: A prospective multi-step study of the potential added benefit of two novel assessment tools in colorectal liver metastases technical resectability decision-making

INTRODUCTION

Liver resection is the only curative treatment for colorectal liver metastases (CLM). Resectability decision-making is therefore a key determinant of outcomes. Wide variation has been demonstrated in resectability decision-making, despite the existence of criteria. This paper summarises a study protocol to evaluate the potential added value of two novel assessment tools in assessing CLM technical resectability: the Hepatica preoperative MR scan (MR-based volumetry, Couinaud segmentation, liver tissue characteristics and operative planning tool) and the LiMAx test (hepatic functional capacity).

METHODS AND ANALYSIS

This study uses a systematic multistep approach, whereby three preparatory workstreams aid the design of the final international case-based scenario survey:Workstream 1: systematic literature review of published resectability criteria.Workstream 2: international hepatopancreatobiliary (HPB) interviews.Workstream 3: international HPB questionnaire.Workstream 4: international HPB case-based scenario survey.The primary outcome measures are change in resectability decision-making and change in planned operative strategy, resulting from the novel test results. Secondary outcome measures are variability in CLM resectability decision-making and opinions on the role for novel tools.

ETHICS AND DISSEMINATION

The study protocol has been approved by a National Health Service Research Ethics Committee and registered with the Health Research Authority. Dissemination will be via international and national conferences. Manuscripts will be published.

REGISTRATION DETAILS

The CoNoR Study is registered with ClinicalTrials.gov (registration number NCT04270851). The systematic review is registered on the PROSPERO database (registration number CRD42019136748).

Obesity at age 20 and weight gain during adulthood increase risk of total and premature all-cause mortality: findings from women attending breast screening in Manchester

BACKGROUND

Obesity in early adulthood is associated with lower breast cancer rates in later life. This could be interpreted as a positive reinforcement of excess weight amongst younger women however, the wider implications of higher weights are less well known. This study examined the association between both obesity in early adulthood and body mass index (BMI) change through adulthood, and all-cause mortality.

METHODS

The Predicting Risk of Cancer At Screening (PROCAS) study recruited 57,902 women aged 46-73 years (median age 57.2, IQR 51.8-63.7 years) from the Greater Manchester National Health Service breast screening programme in North West England between 2009 and 2015. It was used to assess associations between BMI at 20 years and cohort entry with all-cause mortality ascertained via deaths recorded on the National Breast Screening System to June 2020. Hazard ratios were estimated using proportional hazards (Cox) regression adjusted for factors at entry to the cohort: age, deprivation, bilateral oophorectomy, hormone-replacement therapy, menopausal status, ethnicity, alcohol intake, physical activity, and BMI.

RESULTS

The prevalence of overweight (25-30 kg/m²) and obesity (> 30 kg/m²) were 10.4% and 2.5% respectively at 20 years, increasing to 35.2% and 25.9% respectively at cohort entry. After a mean 8.7 years follow-up we observed that overweight (HR = 1.27, 95%CI = 1.10-1.47) and obesity (HR = 2.11, 95%CI = 1.67-2.66) at 20 years had a higher mortality rate compared with healthy weight. Women who were underweight/healthy weight at 20 years and gained weight to obesity at entry had a slightly increased mortality rate compared with women who were underweight/healthy weight at both time points (HR 1.16, 95%CI = 1.02-1.32). Women with overweight (HR = 1.36, 95%CI = 1.06-1.75) or obesity (HR = 1.90, 95%CI = 1.45-2.48) at both 20 years and entry had a higher mortality rate than women who were underweight/healthy weight at both points.

CONCLUSIONS

Women who self-reported overweight and obesity at 20 years had a shorter life expectancy in this cohort of women attending breast cancer screening. Weight gain from 20 years was common in this group. Girls and women should be supported to maintain a healthy weight throughout the lifespan to help increase life expectancy. Trial registration number NCT04359420, retrospectively registered 24/04/2020.

Patterns and Timing of Recurrence following CRS and HIPEC in Colorectal Cancer Peritoneal Metastasis

INTRODUCTION

Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy (CRS/HIPEC) is an established treatment of Colorectal Peritoneal Metastases (CRPM). This study aims to determine the timing and patterns of recurrent disease on imaging following complete CRS/HIPEC.

METHODS

Retrospective analysis of a national peritoneal tumour service database identified CRPM patients with complete CRS/HIPEC(CC0) from 2005 to-2018. Patients with<2 years follow-up or and those where post-operative histology from the CRS/HIPEC procedure did not confirm CRPM from their original colorectal cancer were excluded. Time to recurrence was measured from surgery to first radiologically illustrated recurrence. CT was the primary modality used, supplemented by PET-CT or MRI if required. Outcomes of interest were survival data (including overall survival (OS), disease-free survival (DFS) and peritoneal-recurrence free survival (PRFS)), timing and patterns of recurrent disease.

RESULTS

146 of the 176 patients identified were eligible for inclusion. Median OS for all study patients was 45.2 months (95% CI 38-53 months), median DFS was 11.7 months (95% CI 9-14 months), and median PRFS was 25.2 months (95% CI 14.7-30 months). Recurrent disease was seen in 112 cases (77%), radiologically classified as intraperitoneal in 50 patients (44%), single site systemic in 21 patients (19%) and multi-site in 41 patients (37%). CT detection rate for disease recurrence was 88%. Subgroup analyses showed that PCI ≥12, positive nodal primary disease and synchronous peritoneal disease were associated with worse outcomes.

CONCLUSION

Patients selected for CRS/HIPEC for CRPM have an OS > 45 months, with the majority recurring systemically within a year. Peritoneal recurrence is a later event after several years. Surveillance programs in this group should be most intensive in the first 2 years after surgery, using CT with oral and intravenous contrast.

Establishing a colorectal cancer research database from routinely collected health data: the process and potential from a pilot study

Objective

Colorectal cancer is a common cause of death and morbidity. A significant amount of data are routinely collected during patient treatment, but they are not generally available for research. The National Institute for Health Research Health Informatics Collaborative in the UK is developing infrastructure to enable routinely collected data to be used for collaborative, cross-centre research. This paper presents an overview of the process for collating colorectal cancer data and explores the potential of using this data source.

Methods

Clinical data were collected from three pilot Trusts, standardised and collated. Not all data were collected in a readily extractable format for research. Natural language processing (NLP) was used to extract relevant information from pseudonymised imaging and histopathology reports. Combining data from many sources allowed reconstruction of longitudinal histories for each patient that could be presented graphically.

Results

Three pilot Trusts submitted data, covering 12 903 patients with a diagnosis of colorectal cancer since 2012, with NLP implemented for 4150 patients. Timelines showing individual patient longitudinal history can be grouped into common treatment patterns, visually presenting clusters and outliers for analysis. Difficulties and gaps in data sources have been identified and addressed.

Discussion

Algorithms for analysing routinely collected data from a wide range of sites and sources have been developed and refined to provide a rich data set that will be used to better understand the natural history, treatment variation and optimal management of colorectal cancer.

Conclusion

The data set has great potential to facilitate research into colorectal cancer.

Clinico-pathological predictors of clinical complete response in rectal cancer

PURPOSE

Prediction of clinical complete response in rectal cancer before neoadjuvant chemo-radiotherapy treatment enables treatment selection. Patients predicted to have complete response could have chemo-radiotherapy, and others could have additional doublet chemotherapy at this stage of their treatment to improve their overall outcome. This work investigates the role of clinical variables in predicting clinical complete response.

METHOD

Using the UK-based OnCoRe database (2008 to 2019), we performed a propensity-score matched study of 322 patients who received neoadjuvant chemoradiotherapy. We collected pre-treatment clinic-pathological, inflammatory and radiotherapy-related characteristics. We determined the odds for the occurrence of cCR using conditional logistic regression models. We derived the post-model Area under the Curve (AUC) as an indicator of discrimination performance and stated a priori that an AUC of 0.75 or greater was required for potential clinical utility.

RESULTS

Pre-treatment tumour diameter, mrT-stage, haemoglobin, alkaline phosphate and total radiotherapy depths were associated with cCR on univariable and multivariable analysis. Additionally, neutrophil to lymphocyte ratio (NLR), neutrophil-monocyte to lymphocyte ratio (NMLR), lymphocyte count and albumin were all significantly associated with cCR on multivariable analysis. A nomogram using the above parameters was developed with a resulting ROC AUC of 0.75.

CONCLUSION

We identified routine clinic-pathological, inflammatory and radiotherapy-related variables which are independently associated with cCR. A nomogram was developed to predict cCR. The performance characteristics from this model were on the prior clinical utility threshold. Additional research is required to develop more associated variables to better select patients with rectal cancer undergoing chemoradiotherapy who may benefit from pursuing a W&W strategy.

TP9.2.21Laparoscopy in Emergency General Surgery (The LEGS Study): NELA Database Analysis -Comparison of Outcomes in Laparoscopic versus Open Surgery

Introduction

Guidelines suggest the laparoscopic approach may be safe and feasible in emergency general surgery. Despite this, the UK National Emergency Laparotomy Audit (NELA) rate of laparoscopic surgery remains low. Our earlier analysis of the NELA database identified factors associated with use of laparoscopy, then recommended further analysis to compare outcomes between laparoscopic and open surgery.

Methods

We obtained information from the NELA database (2013 - 2017) and performed logistic regression on all first operations during the hospital admission. Outcomes were compared between open and laparoscopic approach (fully laparoscopic, laparoscopic assisted and laparoscopic converted). The primary outcome was death during hospital admission; secondary outcomes were admission to intensive care unit (ICU), length of ICU stay and return to theatre.

Results

The cohort comprised 68,928 open (52% men, mean age 65) and 12,144 laparoscopic (51% men, mean age 58). In a model adjusted for all factors influencing primary or secondary outcomes (age, gender, p-possum, weekday versus weekend, operative time of day, malignancy, peritoneal soiling, CEPOD urgency, surgical grade and anaesthetist grade), death rates were significantly lower in the laparoscopic group (OR 0.65, 95% CI 0.59 – 0.71). Post-operative admission to ICU and ICU stay &gt; 3 days were both significantly lower in the laparoscopic group (OR 0.59, 95% CI 0.56 – 0.62; OR 0.82, CI 0.75 – 0.89). There was no difference in return to theatre.

Conclusions

Outcomes for laparoscopy in emergency general surgery appear superior to open surgery, although there may be residual unmeasured confounding factors. Further analysis will compare outcomes between pathologies.

O5: THE CLIFF AND CONOR STUDIES NOVEL ASSESSMENT TOOLS IN COLORECTAL LIVER METASTASES (CLIFF STUDY - CHANGE IN LIVER FUNCTION AND FAT IN PRE-OPERATIVE CHEMOTHERAPY FOR COLORECTAL LIVER METASTASES, CONOR STUDY

Introduction

Hepatic resection is the only potentially curative treatment for patients with colorectal liver metastases (CLM). Patient selection is key, but there is wide variation in practice. Pre-operative chemotherapy can improve oncological outcomes, however chemotherapy-associated liver injury (CALI) may hinder liver regenerative capacity. Standard pre-operative assessments fail to accurately capture factors such as CALI and future liver remnant (FLR) function. The CLiFF and CoNoR studies utilise two novel assessment techniques, aiming to improve patient outcomes.

Method

The CLiFF study prospectively assesses two primary outcomes in 35 patients undergoing pre-operative chemotherapy for CLM: 1) change in liver function (via LiMAx test: direct assessment of hepatic functional capacity), and 2) change in liver fat (via advanced MR imaging (in-house spectroscopy and modified Dixon technique, scaled up via Perspectum LiverMultiScan)). The CoNoR study assesses potential added benefit of these novel tools in CLM resectability decision-making via sequential workstreams: a systematic review and international hepatobiliary expert interviews inform the online survey, assessing added benefit via online MDT scenarios.

Result

Preliminary CLiFF analysis suggests that CALI changes in liver fat and function are unrelated. Liver fat analysis techniques are compared and correlated with digital histological analysis. The CoNoR systematic review identifies key factors influencing CLM resectability decision-making and informs the international expert interviews, scheduled to occur during a February 2020 international hepatobiliary conference.

Conclusion

These studies are the first to assess where these novel tools might be utilised to maximal patient benefit within the Hepatobiliary MDT, and the first systematic review in CLM resectability decision-making.

Take-home message

These two linked studies evaluate the use of two novel assessment tools in the treatment of colorectal liver metastases, with the potential to improve patient selection for curative resection and patient outcomes.

PATEY PRIZE SESSION

Long-term outcomes for patients with peritoneal acellular mucinosis secondary to low grade appendiceal mucinous neoplasms

INTRODUCTION

Low grade appendiceal mucinous neoplasms (LAMN) are known to metastasise to the peritoneum resulting in pseudomyxoma peritonei (PMP). Literature suggests that the long-term outcome is dependent on the cellular grade of the peritoneal histology, less is known about the risk to patients with acellular mucinosis (AM) alone. This study aims to review long-term outcomes in patients with PMP treated with Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy (CRS/HIPEC), whose peritoneal histology was AM secondary to LAMN.

METHODS

Pathological and treatment outcomes were collected from a prospectively maintained database between 2005 and 2019. Data was collected on patients with LAMN and AM diagnosed following CRS/HIPEC. A single institution performed the surgery and pathology reporting, samples reported by three different pathologists.

RESULTS

Of the 2079 patients with any appendiceal neoplasm referred between 2005 and 2019, 809 underwent CRS/HIPEC, 67 (8%) of those had PMP with purely AM secondary to a LAMN. In the AM group the median age was 59, 37 (55%) were female, follow up was for a median 39 (2-145) months. Inpatient mortality occurred in 1 patient (1.5%), disease specific mortality in 2 (3%), recurrence in 2 (3%) and disease progression in 1 (1.5%).

CONCLUSION

This study has identified AM secondary to LAMN as a low risk group for recurrence following CRS/HIPEC compared with epithelial pathology. Given such a low rate of recurrence we would recommend low intensity surveillance post CRS/HIPEC. Agreed standardised pathological assessment is required to exclude cellular material in specimens and diagnose AM.

Prospective study of change in liver function and fat in patients with colorectal liver metastases undergoing preoperative chemotherapy: protocol for the CLiFF Study

INTRODUCTION

Preoperative chemotherapy in patients undergoing resection for colorectal liver metastases (CLM) improves oncological outcomes. However, chemotherapy-associated liver injury (occurring in two patterns: vascular and fat deposition) is a real clinical concern prior to hepatic resection. After major liver resection, regeneration of the residual liver is a prerequisite for recovery and avoidance of liver failure, but this regenerative capacity may be hindered by chemotherapy. Thus, there is a need to predict for this serious complication. Over the past two decades, several tests and derived indices have been developed, which have failed to achieve clinical utility, mainly as they were indirect measurements of liver function. Here, we will use a novel test of liver function (the liver maximum capacity (LiMAx) test), and measure liver fat using MRI.

METHODS AND ANALYSIS

This prospective study will assess changes in liver function longitudinally, measured by the LiMAx test, and liver fat, measured by advanced MRI using both MR spectroscopy and the modified Dixon method, in up to 35 patients undergoing preoperative chemotherapy for CLM. The primary outcomes will be the changes in liver function and fat compared with baseline prechemotherapy measurements. Secondary outcome measures include: routinely measured liver function blood tests, anthropometric measurements, postoperative histology and digital quantification of fat, postoperative complications and mortality and quality of life.

ETHICS AND DISSEMINATION

The study was approved by a National Health Service Research Ethics Committee and registered with the Health Research Authority. Dissemination will be via international and national conferences and the National Institute for Health Research network. Manuscripts will be published.

TRIAL REGISTRATION NUMBER

This study is registered online at www.clinicaltrials.gov (registration number NCT03562234).

Temporal improvements in loco-regional failure and survival in patients with anal cancer treated with chemo-radiotherapy: treatment cohort study (1990-2014)

Background

We evaluated oncological changes in patients with squamous cell carcinoma of the anus (SCCA) treated by chemoradiotherapy (CRT) from a large UK institute, to derive estimates of contemporary outcomes.

Methods

We performed a treatment-cohort analysis in 560 patients with non-metastatic SCCA treated with CRT over 25 years. The primary outcomes were 3-year loco-regional failure (LRF), 5-year overall survival (OS), and 5-year cancer-specific survival (CSS). We developed prediction models; and overlaid estimates on published results from historic trials.

Results

Age distributions, proportions by gender and cT stage remained stable over time. The median follow-up was 61 (IQR: 36–79) months. Comparing the first period (1990–1994) with the last period (2010–2014), 3-year LRF declined from 33 to 16% (P_trends < 0.001); 5-year OS increased from 60% to 76% (P_trends = 0.001); and 5-year CCS increased from 62% in to 80% (P_trends = 0.001). For 2020, the models predicted a 3-year LRF of 14.7% (95% CIs: 0–31.3); 5-year OS of 74.7% (95% CIs: 54.6–94.9); and 5-year CSS of 85.7% (95% CIs: 75.3–96.0). Reported oncological outcomes from historic trials generally underestimated contemporary outcomes.

Conclusions

Current and predicted rates for 3-year LRF and 5-year survivals are considerably improved compared with those in historic trials.

Quality optimisation in colonoscopy: a function of time of colonoscopy or bowel preparation

To test the hypothesis claimed in recent studies that quality of bowel preparation for colonoscopy could be influenced by the time of the day colonoscopy is performed. Do patients in morning list have better bowel preparation than those on the afternoon list? Retrospective analysis of 736 consecutive patients who had colonoscopy from 1^st August to 31^st December 2012. Patients with poor bowel preparation (Boston Bowel Prep Score 6 or less) were identified (n = 242). Colonoscopy reports of these patients analysed. Patients were stratified into two groups (am and pm) and results compared. Mean patient age 63.9 years (range 19-89). Male to female ratio 1:1. 92% of patients were given Moviprep. for bowel preparation. 32.9% (242/736) of patients were identified as having inadequate bowel preparation. 37.7% of morning list patients had poor bowel preparation. 26.7% of afternoon list patients had poor bowel preparation. 14.7% (108/736) had incomplete colonoscopy, of which 26.9% (29/108) were due to poor bowel preparation. The commonest reasons for incomplete examination were patient discomfort & bowel looping. Our study demonstrates that morning session patients had poorer bowel preparation than the afternoon session patients in contrast to published evidence in recent literature. This implies that timing of bowel preparation is probably more important than timing of colonoscopy. Poor bowel preparation does not seem to have a significant impact on the colonoscopy failure rate in this series.

Factors affecting local regrowth after watch and wait for patients with a clinical complete response following chemoradiotherapy in rectal cancer (InterCoRe consortium): an individual participant data meta-analysis

BACKGROUND

In patients with rectal cancer who achieve clinical complete response after neoadjuvant chemoradiotherapy, watch and wait is a novel management strategy with potential to avoid major surgery. Study-level meta-analyses have reported wide variation in the proportion of patients with local regrowth. We did an individual participant data meta-analysis to investigate factors affecting occurrence of local regrowth.

METHODS

We updated search results of a recent systematic review by searching MEDLINE and Embase from Jan 1, 2016, to May 5, 2017, and used expert knowledge to identify published studies reporting on local regrowth in patients with rectal cancer managed by watch and wait after clinical complete response to neoadjuvant chemoradiotherapy. We restricted studies to those that defined clinical complete response using criteria equivalent to São Paulo benchmarks (ie, absence of residual ulceration, stenosis, or mass within the rectum on clinical and endoscopic examination). The primary outcome was 2-year cumulative incidence of local regrowth, estimated with a two-stage random-effects individual participant data meta-analysis. We assessed the effects of clinical and treatment factors using Cox frailty models, expressed as hazard ratios (HRs). From these models, we derived percentage differences in mean θ as an approximation of the effect of measured covariates on between-centre heterogeneity. This study is registered with PROSPERO, number CRD42017070934.

FINDINGS

We obtained individual participant data from 11 studies, including 602 patients enrolled between March 11, 1990, and Feb 13, 2017, with a median follow-up of 37·6 months (IQR 25·0-58·7). Ten of the 11 datasets were judged to be at low risk of bias. 2-year cumulative incidence of local regrowth was 21·4% (random-effects 95% CI 15·3-27·6), with high levels of between-study heterogeneity (I²=61%). We noted wide between-centre variation in patient, tumour, and treatment characteristics. We found some evidence that increasing cT stage was associated with increased risk of local regrowth (random-effects HR per cT stage 1·40, 95% CI 1·00-1·94; p_trend=0·048). In a subgroup of 459 patients managed after 2008 (when pretreatment staging by MRI became standard), 2-year cumulative incidence of local regrowth was 19% (95% CI 13-28) for stage cT1 and cT2 tumours, 31% (26-37) for cT3, and 37% (21-60) for cT4 (random-effects HR per cT stage 1·50, random-effects 95% CI 1·03-2·17; p_trend=0·0330). We estimated that measured factors contributed 4·8-45·3% of observed between-centre heterogeneity.

INTERPRETATION

In patients with rectal cancer and clinical complete response after chemoradiotherapy managed by watch and wait, we found some evidence that increasing cT stage predicts for local regrowth. These data will inform clinician-patient decision making in this setting. Research is needed to determine other predictors of a sustained clinical complete response.

FUNDING

None.

Nodal stage migration and prognosis in anal cancer: a systematic review, meta-regression, and simulation study

BACKGROUND

In patients with squamous cell carcinoma of the anus (SCCA), lymph node positivity (LNP) indicates poor prognosis for survival and is central to radiotherapy planning. Over the past three decades, LNP proportion has increased, mainly reflecting enhanced detection with newer imaging modalities; a process known as nodal stage migration. If accompanied by constant T stage distributions, prognosis for both lymph node-positive and lymph node-negative groups may improve without any increase in overall survival for individual patients; a paradox termed the Will Rogers phenomenon. Here, we aim to systematically evaluate the impact of nodal stage migration on survival in SCCA and address a novel hypothesis that this phenomenon results in reduced prognostic discrimination.

METHODS

We did a systematic review and meta-regression to quantify changes in LNP over time and the impact of this change on survival and prognostic discrimination. We searched MEDLINE, Embase, and the Cochrane Library to identify randomised trials and observational studies in patients with SCCA published between Jan 1, 1970, and Oct 11, 2016. Studies were eligible if patients received chemoradiotherapy or radiotherapy as the main treatment, reported LNP proportions (all studies), and reported overall survival (not necessarily present in all studies). We excluded studies with fewer than 50 patients. We extracted study-level data with a standardised, piloted form. The primary outcome measure was 5-year overall survival. To investigate scenarios in which reduced prognostic discrimination might occur, we simulated varying true LNP proportions and true overall survival, and compared these with expected observed outcomes for varying levels of misclassification of true nodal state.

FINDINGS

We identified 62 studies reporting LNP proportions, which included 10 569 patients. From these, we included 45 studies (6302 patients) with whole cohort 5-year overall survival, 11 studies with 5-year survival stratified by nodal status, and 20 studies with hazard ratios in our analyses of temporal changes. In 62 studies, the LNP proportions increased from a mean estimate of 15·3% (95% CI 10·5-20·1) in 1980 to 37·1% (34·0-41·3) in 2012 (p<0·0001). In 11 studies with prognostic data, increasing LNP was associated with improved overall survival in both lymph node-positive and lymph node-negative categories, whereas the proportions with combined tumour stage T3 and T4 remained constant. In 20 studies, across a range of LNP proportions from 15% to 40%, the hazard ratios for overall survival of lymph node-positive versus lymph node-negative patients decreased significantly from 2·5 (95% CI 1·8-3·3) at 15% LNP to 1·3 (1·2-1·9; p=0·014) at 40% LNP. The simulated scenarios reproduced this effect if the true LNP proportions were 20% or 25%, but not if the true LNP proportions were 30% or greater.

INTERPRETATION

We describe a consequence of staging misclassification in anal cancer that we have termed reduced prognostic discrimination. We used this new observation to infer that the LNP proportions of more than 30% seen in modern clinical series (11 out of 15 studies with a median year since 2007) are higher than the true LNP proportion. The introduction of new staging technologies in oncology might misclassify true disease stage, spuriously informing disease management and ultimately increasing the risk of overtreatment.

FUNDING

Bowel Disease Research Foundation.

Defunctioning stoma- a prognosticator for leaks in low rectal restorative cancer resection: A retrospective analysis of stoma database

AIMS

Low anterior resection (LAR) has higher risk of anastomotic leak with its attendant morbidity -mortality. De-functioning loop ileostomy (DLI), claimed to mitigate the consequences of anastomotic leak, has been questioned in recent years. This study aims to evaluate the impact of ileostomy on LAR.

METHODS

A retrospective analysis of stoma database. 136 patients with stoma (March 2011-July 2015) were assessed. Data was analysed in respect to LAR anastomotic leak rate, impact on morbidity-mortality, short and long-term stoma complications, rate of ileostomy reversal and reasons for non-reversal.

RESULTS

45 patients had loop ileostomy for LAR. Male (28) to female (17) ratio was 1.65:1 with median age of 69 (IQR: 56-75.5). Only 3 anastomotic leaks (3/45, 6.5%) occurred, all treated conservatively with no mortality. 29 had reversal, average reversal time is 10 months (3-24) and 5 awaiting. Reasons for non-reversal included patients' choice (7), death from cardiac cause (1), chemotherapy (1), unfit for surgery (1) and failed reversal (1). Acute complications included high output & reversible AKI (1), bleeding (3) and minor complications (6) as skin excoriation, separation and appliance issues. Parastomal hernia was repaired during reversal (12/15).

CONCLUSIONS

De-functioning ileostomy for LAR is a safe procedure with low morbidity. Most stomas are reversible. Series highlights a late reversal contrary to the nationally recommended guidelines. Most interestingly, the study demonstrated de-functioning mitigated clinical consequences of anastomotic leak to an extent that reoperation was avoidable, in keeping with recent meta-analysis indicating a significantly low anastomotic leakage rates and reoperation. Larger study is invaluable to substantiate findings.

Watch-and-wait approach versus surgical resection after chemoradiotherapy for patients with rectal cancer (the OnCoRe project): a propensity-score matched cohort analysis

BACKGROUND

Induction of a clinical complete response with chemoradiotherapy, followed by observation via a watch-and-wait approach, has emerged as a management option for patients with rectal cancer. We aimed to address the shortage of evidence regarding the safety of the watch-and-wait approach by comparing oncological outcomes between patients managed by watch and wait who achieved a clinical complete response and those who had surgical resection (standard care).

METHODS

Oncological Outcomes after Clinical Complete Response in Patients with Rectal Cancer (OnCoRe) was a propensity-score matched cohort analysis study, that included patients of all ages diagnosed with rectal adenocarcinoma without distant metastases who had received preoperative chemoradiotherapy (45 Gy in 25 daily fractions with concurrent fluoropyrimidine-based chemotherapy) at a tertiary cancer centre in Manchester, UK, between Jan 14, 2011, and April 15, 2013. Patients who had a clinical complete response were offered management with the watch-and-wait approach, and patients who did not have a complete clinical response were offered surgical resection if eligible. We also included patients with a clinical complete response managed by watch and wait between March 10, 2005, and Jan 21, 2015, across three neighbouring UK regional cancer centres, whose details were obtained through a registry. For comparative analyses, we derived one-to-one paired cohorts of watch and wait versus surgical resection using propensity-score matching (including T stage, age, and performance status). The primary endpoint was non-regrowth disease-free survival from the date that chemoradiotherapy was started, and secondary endpoints were overall survival, and colostomy-free survival. We used a conservative p value of less than 0·01 to indicate statistical significance in the comparative analyses.

FINDINGS

259 patients were included in our Manchester tertiary cancer centre cohort, 228 of whom underwent surgical resection at referring hospitals and 31 of whom had a clinical complete response, managed by watch and wait. A further 98 patients were added to the watch-and-wait group via the registry. Of the 129 patients managed by watch and wait (median follow-up 33 months [IQR 19-43]), 44 (34%) had local regrowths (3-year actuarial rate 38% [95% CI 30-48]); 36 (88%) of 41 patients with non-metastatic local regrowths were salvaged. In the matched analyses (109 patients in each treatment group), no differences in 3-year non-regrowth disease-free survival were noted between watch and wait and surgical resection (88% [95% CI 75-94] with watch and wait vs 78% [63-87] with surgical resection; time-varying p=0·043). Similarly, no difference in 3-year overall survival was noted (96% [88-98] vs 87% [77-93]; time-varying p=0·024). By contrast, patients managed by watch and wait had significantly better 3-year colostomy-free survival than did those who had surgical resection (74% [95% CI 64-82] vs 47% [37-57]; hazard ratio 0·445 [95% CI 0·31-0·63; p<0·0001), with a 26% (95% CI 13-39) absolute difference in patients who avoided permanent colostomy at 3 years between treatment groups.

INTERPRETATION

A substantial proportion of patients with rectal cancer managed by watch and wait avoided major surgery and averted permanent colostomy without loss of oncological safety at 3 years. These findings should inform decision making at the outset of chemoradiotherapy.

FUNDING

Bowel Disease Research Foundation.