Systematic review of outcome measures following chemoradiotherapy for the treatment of anal cancer (CORMAC).

AIM: Six Phase III randomized trials have determined the effectiveness of chemoradiotherapy as primary treatment for anal squamous cell carcinoma (ASCC), but outcomes reported in these trials varied widely, hindering evidence synthesis. To improve reporting in all future trials, we aim to develop a core outcomes set (COS). As the first stage of COS development, we undertook a systematic review to summarize the outcomes reported in studies evaluating chemoradiotherapy for ASCC. METHOD: Systematic literature searches identified studies evaluating radiotherapy or chemoradiotherapy for ASCC. Outcomes and accompanying definitions were extracted verbatim and categorized into domains. RESULTS: From 5170 abstracts, we identified 95 eligible studies, reporting 1192 outcomes and 533 unique terms. We collapsed these terms into 86 standardized outcomes and five domains: survival; disease activity; life impact [including quality of life (QoL)]; delivery of care; and toxicity. The most commonly reported domains were survival and disease activity, reported in 74 (86%) and 54 (62%) studies, respectively. No outcome was reported in every publication. Over half (43/86) of the standardized outcome terms were reported in fewer than five studies, and 21 (25%) were reported in a single study only. There was wide variation in definitions of disease-free survival, colostomy-free survival and progression-free survival (PFS). Anal continence was reported in only 35 (41%) studies. CONCLUSION: Outcomes reported in studies evaluating chemoradiotherapy for ASCC were heterogenous and definitions varied widely. Outcomes likely to be important to patients, such as ano-rectal function, toxicity and QoL, have been neglected. A COS for future trials will address these issues.

Referral and treatment pathways for pseudomyxoma peritonei of appendiceal origin within a national treatment programme.

AIM: Pseudomyxoma peritonei (PMP) is a rare neoplasm of the appendix, which if untreated disseminates throughout the abdominal cavity and generates considerable morbidity. Since 2002 in the UK, patients with PMP have been managed via two nationally commissioned centres. We evaluated referrals and treatment pathways over time at the Manchester centre. METHOD: Data from all patients referred with suspected PMP were prospectively collected (2002-2015). Definitive treatment was cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy. Disease burden was quantified using the Peritoneal Cancer Index (PCI) (score 0-39) and complete cytoreduction (CC) defined by scores of 0/1. Novel treatment algorithms were developed for patients with low grade appendiceal mucinous neoplasm (LAMN) localized to the peri-appendiceal tissue. RESULTS: In all, 817 patients with confirmed PMP were referred increasing from 11 in 2002 to 103 in 2015. Disease burden was high with a mean PCI of 31 in the first quartile (Q1), levelling off to 15, 15, 17 thereafter (P = 0.002). The proportion of CC0/1 increased from 67% in Q1 to 77% Q2 and 74% Q3/4. Where complete cytoreduction was achieved, 5- and 10-year overall survival was 77% and 66%. The proportion of patients referred with localized LAMN increased over time reaching 25% each year since 2010 (Ptrend  < 0.0001). Two-thirds of localized LAMN now undergo laparoscopically assisted risk-reducing CRS. CONCLUSION: The establishment of a national treatment centre was associated with an initial presentation of patients with advanced disease. The programme has demonstrated a clear trend over time towards earlier referral and adoption of minimally invasive techniques for localized disease.

Measuring the biological effect of presurgical metformin treatment in endometrial cancer.

BACKGROUND: Preclinical studies in endometrial cancer (EC) show that metformin reduces cellular proliferation by PI3K-AKT-mTOR inhibition. We tested the hypothesis that short-term presurgical metformin reduces cellular proliferation in atypical endometrial hyperplasia (AEH) and endometrioid EC, and assessed the feasibility of using phosphorylated PI3K-AKT-mTOR proteins as tissue end points. METHODS: Women with AEH or EC received metformin 850 mg twice a day or no drug in the presurgical window between diagnosis and hysterectomy. Before and after the window, tissue samples were obtained; serum markers of insulin resistance (e.g. homeostasis model of assessment of insulin resistance index) were determined; and anthropometrics measured (e.g. BMI). Cell proliferation (Ki-67) and PI3K-AKT-mTOR phosphostatus were assessed by immunohistochemistry and scored blinded to treatment. RESULTS: Twenty-eight metformin-treated and 12 untreated patients, well matched for age and BMI, completed the study. Metformin treatment (median 20 days, range 7-34) was associated with a 17.2% reduction in tumour Ki-67 (95% CI -27.4, -7.0, P=0.002), in a dose-dependent manner. Tumour PI3K-AKT-mTOR protein phosphostatus varied but the effects were not significant after adjusting for changes in controls. CONCLUSIONS: Short-term metformin was associated with reduced Ki-67 expression in EC. Changes in tumour PI3K-AKT-mTOR protein phosphostatus were seen in both groups. Future studies should address the variability attributed to different sampling techniques including devascularisation of the uterus at hysterectomy.

Slowing down of adult body mass index trend increases in England: a latent class analysis of cross-sectional surveys (1992-2010).

BACKGROUND: The prevalence of excess body weight, commonly measured as body mass index (BMI)≥25 kg m(-2), has increased substantially in many populations worldwide over the past three decades, but the rate of increase has slowed down in some western populations. OBJECTIVE: We address the hypothesis that the slowing down of BMI trend increases in England reflects a majority sub-population resistant to further BMI elevation. DESIGN: Pseudo-panel data derived from annual cross-sectional surveys, the Health Surveys for England (1992-2010). Trends in median BMI values were explored using regression models with splines, and gender-specific mixture model (latent class analysis) were fit to take an account of increasing BMI distribution variance with time and identify hidden subgroups within the population. SUBJECTS: BMI was available for 164 155 adults (men: 76 382; women: 87 773). RESULTS: Until 2001, the age-adjusted yearly increases in median BMI were 0.140 and 0.139 kg m(-2) for men and women, respectively, decreasing thereafter to 0.073 and 0.055 kg m(-2) (differences between time periods, both P-values<0.0001). The mixture model identified two components--a normal BMI and a high BMI sub-population--the proportions for the latter were 23.5% in men and 33.7% in women. The remaining normal BMI populations were 'resistant' with minimal increases in mean BMI values over time. By age, mean BMI values in the normal BMI sub-population increased greatest between 20 and 34 years for men; for women, the increases were similar throughout age groups (slope differences, P<0.0001). CONCLUSION: In England, recent slowing down of adult BMI trend increases can be explained by two sub-populations--a high BMI sub-population getting 'fatter' and a majority 'resistant' normal BMI sub-population. These findings support a targeted, rather than a population-wide, policy to tackle the determinants of obesity.

Excess adiposity and gastrointestinal cancer.

BACKGROUND: Excess adiposity is a risk factor for incidence of several gastrointestinal cancers, but it is unclear how these epidemiological observations translate into clinical practice. METHODS: Critical appraisals and updated analyses of published systematic reviews were undertaken to quantify cancer risk associations better and to assess the impact of weight-reducing strategies (surgical and non-surgical) on cancer prevention. RESULTS AND CONCLUSION: A large volume of evidence demonstrates that body mass index (BMI), as an approximation for general adiposity, is a risk factor for the development of oesophageal adenocarcinoma, and colorectal, hepatocellular, gallbladder and pancreatic cancers. A smaller volume of evidence demonstrates that indices of increased central adiposity (such as waist circumference) are associated with increased risk of oesophageal adenocarcinoma and colorectal cancer, but these indices are not necessarily better predictors of risk compared with BMI. Several biological mechanisms may explain these associations but each hypothesis has several caveats and weaknesses. There are few data that convincingly demonstrate significant reductions in risk of gastrointestinal cancers following weight-reducing strategies. In turn, there are many methodological pitfalls in this literature, which prevent conclusive interpretation. The lack of robust intermediary obesity-related biomarkers is an additional unresolved challenge for prevention trials. Novel underpinning mechanisms (for example, local ectopic fat) and more accurate methods to measure these intermediaries are sought and explored as the most optimistic research strategies for the future.

Chronic insulin exposure does not cause insulin resistance but is associated with chemo-resistance in colon cancer cells.

Insulin resistance is an adaptive process in insulin-sensitive tissues characterised by reduced insulin receptor (IR) and insulin-receptor substrate (IRS)-1 expression, increased IRS-1 serine phosphorylation and attenuated downstream signalling. We tested whether this molecular phenotype prevails in cancer cells after long-term exposure to insulin. We characterised expression of IR-related molecules, IRS-1 phosphorylation and downstream signalling in a panel of 5 colon cancer cell lines at different insulin exposures: 15 min (100 nM), approximating to acute stimulation; 48 h (100 nM), used to demonstrate adaptive changes; and 12 weeks (20 nM; chronic insulin exposure, CIE), approximating to chronic hyperinsulinaemia. To assess clinical relevance, we determined IC50 values (increased indicating chemo-resistance) in the CIE-treated cells using oxaliplatin, SN38 (irinotecan) and 5-fluorouracil (5-FU). All colon cancer cell lines (HCT 116, HT-29, C32, CaCo2, LoVo) were sensitive to 15 min insulin exposure with increased phosphorylation of Akt, PRAS40 and p70-S6K. At 48 h, there was incomplete or absent features of insulin resistance. In CIE-treated cells, there was reduced IR expression, incomplete IRS-1 adaptation, lack of signalling pathway attenuation and contra-adaptive increases in IRS-1 tyrosine phosphorylation in several cell types. In CIE cells, there were multiple examples of increased IC50 values (2- to 100-fold) following 24-h treatment with oxaliplatin and SN38, but not with 5-FU. We concluded that CIE in colon cancer cells does not completely induce an insulin resistance molecular phenotype but is associated with chemo-resistance. Adaptive changes seen in insulin-sensitive non-neoplastic cells in response to long-term insulin may not extrapolate to neoplastic cells.

The interaction between prognostic and pharmacodynamic biomarkers.

BACKGROUND: Interactions between prognostic and pharmacodynamic (PD) biomarkers have received little attention. METHODS: Prognostic and PD utilities were assessed with linear mixed-effects models using published data on repeated measurements of circulating caspase-cleaved (ctCK18) and total (tCK18) cytokeratin 18, in 57 patients with metastatic colorectal cancer undergoing chemotherapy. RESULTS: The model for tCK18 (but not cCK18) separated the prognostic/PD interaction from the pure prognostic effect, illustrating the principle of dual prognostic and PD characteristics for a given biomarker. CONCLUSION: These models provide the framework for the analysis and interpretation of longitudinal data to detect prognostic/PD biomarker interactions.

Insulin analogues and cancer risk: the emergence of second-generation studies.

A number of observational studies have linked insulin glargine (A21Gly,B31Arg,B32Arg human insulin) with a putative increased cancer risk, particularly breast cancer, but many of these 'first generation' studies had study design and analysis flaws, and were inconclusive. A small number of 'second generation' studies are now emerging in which the applied pharmaco-epidemiological principles are more robust. For example, when Ruitar and colleagues (Diabetologia DOI: 10.1007/s00125-011-2312-4 ) focused specifically on breast cancer rather than all incident cancer risk, they were able to show a positive association with insulin glargine for breast cancer although there was no association with all incident cancer risk. A list of preferred qualities for pharmaco-epidemiological studies is presented.

Diabetes and cancer (1): evaluating the temporal relationship between type 2 diabetes and cancer incidence.

Substantial evidence suggests that people with type 2 diabetes have an increased risk of developing several types of cancers. These associations may be due to a number of direct and indirect mechanisms. Observational studies of these associations, including the potential role for glucose-lowering therapy, are being increasingly reported, but face a number of methodological challenges. This paper is the first of two review papers addressing methodological aspects underpinning the interpretations of links between diabetes and cancer, and suggests potential approaches to study designs to be considered in observational studies. This paper reviews factors related to cancer incidence in the diabetic population; the second paper relates to studies of cancer mortality.

Diabetes and cancer (2): evaluating the impact of diabetes on mortality in patients with cancer.

In this paper we address methodological aspects of aetiological importance in the link between diabetes and mortality in patients with cancer. We identified nine key points on the cancer pathway at which confounding may arise-cancer screening use, stage at diagnosis, cancer treatment selection, cancer treatment complications and failures, peri-treatment mortality, competing risks for long-term mortality, effects of type 2 diabetes on anti-cancer therapies, effects of glucose-lowering treatments on cancer outcome and differences in tumour biology. Two types of mortality studies were identified: (1) inception cohort studies that evaluate the effect of baseline diabetes on cancer-related mortality in general populations, and (2) cohorts of patients with a cancer diagnosis and pre-existing type 2 diabetes. We demonstrate, with multiple examples from the literature, that pre-existing diabetes affects presentation, cancer treatment, and outcome of several common cancer types, often to varying extents. Diabetes is associated with increased all-cause mortality in cancer patients, but the evidence that it influences cancer-specific mortality is inconsistent. In the absence of data that address the potential biases and confounders outlined in the above framework, we caution against the reporting of cancer-related mortality as a main endpoint in analyses determining the impact of diabetes and glucose-lowering medications on risk of cancer.

Multi-level evidence that circulating CK18 is a biomarker of tumour burden in colorectal cancer.

BACKGROUND: Circulating total cytokeratin 18 (tCK18) and/or caspase cleaved cytokeratin 18 (cCK18) (measured by M65 and M30 enzyme-linked immunosorbent assays (ELISAs), respectively) are used as pharmacodynamic (PD) biomarkers of epithelial cell death in clinical trials. Having validated these ELISAs, we assessed their utility in colorectal cancer (CRC). METHODS: We applied the assays in several settings: 53 controls; 97 patients undergoing surgery and 74 patients with metastatic CRC undergoing chemotherapy (55 first line; 56 patients with repeated sampling through chemotherapy). Prognostic significance was evaluated using Kaplan-Meier life tables and Cox models; PD utility was assessed by analysis of repeated measures. RESULTS: Median cCK18 and tCK18 levels were elevated in patients with cancer (both P=0.0001), and among cancer patients, there were increasing trends from early to advanced stages (both P(trends)=0.0001). Increasing tCK18 predicted for reduced survival after surgery with curative intent (adjusted hazard ratio (HR) for doubling in concentration 1.77, 95% CI: 1.04, 3.01) and after first-line chemotherapy in metastatic disease (adjusted HR per doubling in concentration=1.78, 95% CI: 1.37, 2.30). In patients with progressive disease during chemotherapy, repeated sampling revealed profiles with high baselines and progressive upwardly increases after cycle 1. CONCLUSION: This study provides evidence for cytokeratin 18 (CK18) as a prognostic and PD biomarker in patients with CRC and supports continued deployment of circulating CK18 in biomarker-enhanced trials.

Classification of and cytoreductive surgery for low-grade appendiceal mucinous neoplasms.

BACKGROUND: Low-grade appendiceal mucinous neoplasm (LAMN) is a precursor lesion for pseudomyxoma peritonei (PMP), which, if treated suboptimally, may later disseminate throughout the abdominal cavity. The role of cytoreductive surgery for these relatively early lesions is unclear. METHODS: Clinicopathological details and treatment outcomes of patients with a LAMN and disease limited to the appendix or immediate periappendiceal tissues, referred to a national treatment centre between 2002 and 2009, were evaluated prospectively. RESULTS: Of 379 patients with a diagnosis of PMP, 43 (median age 49 years) had LAMNs localized to the appendix and periappendiceal tissue. Thirty-two patients initially presented with symptoms of acute appendicitis or right iliac fossa pain. Two distinct lesions were identified: type I (disease confined to the appendiceal lumen) and type II (mucin and/or neoplastic epithelium in the appendiceal submucosa, wall and/or periappendiceal tissue, with or without perforation). Type I lesions were managed by a watch-and-wait surveillance policy with serial measurement of tumour markers and computed tomography in 14 of 16 patients. Seventeen of 27 patients with type II lesions underwent risk-reducing cytoreductive surgery and hyperthermic intraperitoneal chemotherapy with low morbidity. After a median follow-up of 40 months, there was no disease progression in either treatment pathway. CONCLUSION: This study identified two LAMN subtypes. Type II lesions have pathological features of increased risk for dissemination and should be considered for risk-reducing cytoreductive surgery.

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.

Indications and outcomes for repeat cytoreductive surgery and heated intra-peritoneal chemotherapy in peritoneal surface malignancy.

INTRODUCTION: Cytoreductive surgery (CRS) and heated intraperitoneal chemotherapy (HIPEC) is offered in specialist centres as a treatment for peritoneal surface tumours. Despite its demonstrated efficacy, intra-abdominal recurrence occurs in 31-57% of patients. The aim of this study is to review the early and long-term outcomes in patients who undergo repeat CRS/HIPEC. MATERIALS AND METHODS: A retrospective review of a prospectively maintained database of patients who had undergone repeat CRS/HIPEC for appendiceal neoplasms and colorectal peritoneal metastases (CRPM) from 2003 to 2019 was performed at a single specialist centre. Data pertaining to both short term outcomes and survival were evaluated. RESULTS: Of 1259 patients who had undergone CRS/HIPEC, 84(6.7%) underwent repeat surgery: 45(53.6%) had pseudomyxoma peritonei (PMP) secondary to low grade appendiceal mucinous neoplasms (LAMN), 21(25.0%) had appendix carcinoma and 18(21.4%) had CRPM. Demographics, intra-operative findings and short-term outcomes were comparable across tumour types and between procedures. Median (95% CI) interval between procedures was 22.7(18.9-26.6) months and was comparable between tumour types. Median (95%CI) overall survival was not reached for the cohort overall or for those with PMP, but was 61.0(32.6-89.4) months for those with appendix cancer and 76.9(47.4-106.4) months for CRPM (p=<0.001). Survival was favourable in the PMP group (HR [95%CI] 0.044 [0.008-0.262]; p = 0.000) and unfavourable in the CC2-3 at index CRS procedure group (HR [95%CI] 25.612 [2.703-242.703]; p = 0.005). CONCLUSION: Our findings demonstrate that repeat cytoredutive surgery with HIPEC can result in favourable survival, especially for patients with PMP when complete cytoreduction is achieved at index operation. We recommend that detailed patient assessment is performed through an expert multidisciplinary team meeting (MDT).