First-line oxaliplatin-based chemotherapy and nivolumab for metastatic microsatellite-stable colorectal cancer-the randomised METIMMOX trial.

BACKGROUND: We evaluated first-line treatment of metastatic microsatellite-stable colorectal cancer with short-course oxaliplatin-based chemotherapy alternating with immune checkpoint blockade. METHODS: Patients were randomly assigned to chemotherapy (the FLOX regimen; control group) or alternating two cycles each of FLOX and nivolumab (experimental group). Radiographic response assessment was done every eight weeks with progression-free survival (PFS) as the primary endpoint. Cox proportional-hazards regression models estimated associations between PFS and relevant variables. A post hoc analysis explored C-reactive protein as signal of responsiveness to immune checkpoint blockade. RESULTS: Eighty patients were randomised and 38 in each group received treatment. PFS was comparable-control group: median 9.2 months (95% confidence interval (CI), 6.3-12.7); experimental group: median 9.2 months (95% CI, 4.5-15.0). The adjusted Cox model revealed that experimental-group subjects aged ≥60 had significantly lowered progression risk (p = 0.021) with hazard ratio 0.17 (95% CI, 0.04-0.76). Experimental-group patients with C-reactive protein <5.0 mg/L when starting nivolumab (n = 17) reached median PFS 15.8 months (95% CI, 7.8-23.7). One-sixth of experimental-group cases (all KRAS/BRAF-mutant) achieved complete response. CONCLUSIONS: The investigational regimen did not improve the primary outcome for the intention-to-treat population but might benefit small subgroups of patients with previously untreated, metastatic microsatellite-stable colorectal cancer. TRIAL REGISTRATION: ClinicalTrials.gov number, NCT03388190 (02/01/2018).

Magnetic resonance imaging of anal cancer: tumor characteristics and early prediction of treatment outcome.

PURPOSE: To analyze tumor characteristics derived from pelvic magnetic resonance imaging (MRI) of patients with squamous cell carcinoma of the anus (SCCA) before and during chemoradiotherapy (CRT), and to compare the changes in these characteristics between scans of responders vs. nonresponders to CRT. METHODS: We included 52 patients with a pelvic 3T MRI scan prior to CRT (baseline scan); 39 of these patients received an additional scan during week 2 of CRT (second scan). Volume, diameter, extramural tumor depth (EMTD), and external anal sphincter infiltration (EASI) of the tumor were assessed. Mean, kurtosis, skewness, standard deviation (SD), and entropy values were extracted from apparent diffusion coefficient (ADC) histograms. The main outcome was locoregional treatment failure. Correlations were evaluated with Wilcoxon's signed rank-sum test and Pearson's correlation coefficient, quantile regression, univariate logistic regression, and area under the ROC curve (AUC) analyses. RESULTS: In isolated analyses of the baseline and second MRI scans, none of the characteristics were associated with outcome. Comparison between the scans showed significant changes in several characteristics: volume, diameter, EMTD, and ADC skewness decreased in the second scan, although the mean ADC increased. Small decreases in volume and diameter were associated with treatment failure, and these variables had the highest AUC values (0.73 and 0.76, respectively) among the analyzed characteristics. CONCLUSION: Changes in tumor volume and diameter in an early scan during CRT could represent easily assessable imaging-based biomarkers to eliminate the need for analysis of more complex MRI characteristics.

A common [18F]-FDG PET radiomic signature to predict survival in patients with HPV-induced cancers.

Locally advanced cervical cancer (LACC) and anal and oropharyngeal squamous cell carcinoma (ASCC and OPSCC) are mostly caused by oncogenic human papillomaviruses (HPV). In this paper, we developed machine learning (ML) models based on clinical, biological, and radiomic features extracted from pre-treatment fluorine-18-fluorodeoxyglucose positron emission tomography ([18F]-FDG PET) images to predict the survival of patients with HPV-induced cancers. For this purpose, cohorts from five institutions were used: two cohorts of patients treated for LACC including 104 patients from Gustave Roussy Campus Cancer (Center 1) and 90 patients from Leeds Teaching Hospitals NHS Trust (Center 2), two datasets of patients treated for ASCC composed of 66 patients from Institut du Cancer de Montpellier (Center 3) and 67 patients from Oslo University Hospital (Center 4), and one dataset of 45 OPSCC patients from the University Hospital of Zurich (Center 5). Radiomic features were extracted from baseline [18F]-FDG PET images. The ComBat technique was applied to mitigate intra-scanner variability. A modified consensus nested cross-validation for feature selection and hyperparameter tuning was applied on four ML models to predict progression-free survival (PFS) and overall survival (OS) using harmonized imaging features and/or clinical and biological variables as inputs. Each model was trained and optimized on Center 1 and Center 3 cohorts and tested on Center 2, Center 4, and Center 5 cohorts. The radiomic-based CoxNet model achieved C-index values of 0.75 and 0.78 for PFS and 0.76, 0.74, and 0.75 for OS on the test sets. Radiomic feature-based models had superior performance compared to the bioclinical ones, and combining radiomic and bioclinical variables did not improve the performances. Metabolic tumor volume (MTV)-based models obtained lower C-index values for a majority of the tested configurations but quite equivalent performance in terms of time-dependent AUCs (td-AUC). The results demonstrate the possibility of identifying common PET-based image signatures for predicting the response of patients with induced HPV pathology, validated on multi-center multiconstructor data.

Nordic anal cancer (NOAC) group consensus guidelines for risk-adapted delineation of the elective clinical target volume in anal cancer.

Background: To date, anal cancer patients are treated with radiotherapy to similar volumes despite a marked difference in risk profile based on tumor location and stage. A more individualized approach to delineation of the elective clinical target volume (CTVe) could potentially provide better oncological outcomes as well as improved quality of life. The aim of the present work was to establish Nordic Anal Cancer (NOAC) group guidelines for delineation of the CTVe in anal cancer.Methods: First, 12 radiation oncologists reviewed the literature in one of the following four areas: (1) previous delineation guidelines; (2) patterns of recurrence; (3) anatomical studies; (4) common iliac and para-aortic recurrences and delineation guidelines. Second, areas of controversy were identified and discussed with the aim of reaching consensus.Results: We present consensus-based recommendations for CTVe delineation in anal cancer regarding (a) which regions to include, and (b) how the regions should be delineated. Some of our recommendations deviate from current international guidelines. For instance, the posterolateral part of the inguinal region is excluded, decreasing the volume of irradiated normal tissue. For the external iliac region and the cranial border of the CTVe, we agreed on specifying two different recommendations, both considered acceptable. One of these recommendations is novel and risk-adapted; the external iliac region is omitted for low-risk patients, and several different cranial borders are used depending on the individual level of risk.Conclusion: We present NOAC consensus guidelines for delineation of the CTVe in anal cancer, including a risk-adapted strategy.

International Validation of the EORTC QLQ-ANL27, a Field Study to Test the Anal Cancer-Specific Health-Related Quality-of-Life Questionnaire.

PURPOSE: The European Organisation for Research and Treatment of Cancer (EORTC) health-related quality of life questionnaire for anal cancer (QLQ-ANL27) supplements the EORTC cancer generic measure (QLQ-C30) to measure concerns specific to people with anal cancer treated with chemoradiotherapy. This study tested the psychometric properties and acceptability of the QLQ-ANL27. METHODS AND MATERIALS: People with anal cancer were recruited from 15 countries to complete the QLQ-C30 and QLQ-ANL27 and provide feedback on the QLQ-ANL27. Item responses, scale structure (multitrait scaling, factor analysis), reliability (internal consistency and reproducibility) and sensitivity (known group comparisons and responsiveness to change) of the QLQ-ANL27 were evaluated. RESULTS: Data from 382 people were included in the analyses. The EORTC QLQ-ANL27 was acceptable, comprehensive, and easy to complete, taking an average 8 minutes to complete. Psychometric analyses supported the EORTC QLQ-ANL27 items and reliability (Cronbach's α ranging from 0.71-0.93 and test-retest coefficients above 0.7) and validity of the scales (particularly nonstoma bowel symptoms and pain/discomfort). Most scales distinguished people according to treatment phase and performance status. Bowel (nonstoma), pain/discomfort, and vaginal symptoms were sensitive to deteriorations over time. The stoma-related scales remained untested because of low numbers of people with a stoma. Revisions to the scoring and question ordering of the sexual items were proposed. CONCLUSIONS: The QLQ-ANL27 has good psychometric properties and is available in 16 languages for people treated with chemoradiotherapy for anal cancer. It is used in clinical trials and has a potential role in clinical practice.

Early radiologic signal of responsiveness to immune checkpoint blockade in microsatellite-stable/mismatch repair-proficient metastatic colorectal cancer.

BACKGROUND: Immune checkpoint blockade (ICB) results in radiologic tumour response dynamics that differ from chemotherapy efficacy measures and require an early signal of clinical utility. METHODS: Previously untreated, unresectable microsatellite-stable (MSS)/mismatch repair-proficient (pMMR) colorectal cancer (CRC) patients were randomly assigned to the oxaliplatin-based Nordic FLOX regimen (control arm) or repeat sequential two FLOX cycles and two ICB cycles (experimental arm). The radiologic response was assessed every 8 weeks. In this post hoc analysis, we explored early target lesion (TL) dynamics as indicator of ICB responsiveness. Progression-free survival (PFS) was the primary endpoint. RESULTS: Using a landmark analysis approach, we categorised experimental-arm patients into ≥10% (N = 19) or <10% (N = 16) TL reduction at the first post-baseline response assessment. Median PFS for the groups was 16.0 (95% confidence interval (CI), 12.3-19.7) and 3.9 months (95% CI, 2.3-5.5), respectively, superior and inferior (both P < 0.01) to the median PFS of 9.8 months (95% CI, 4.9-14.7) for control arm patients (N = 31). CONCLUSIONS: Radiologic TL reduction of ≥10% at the first post-baseline response assessment identified patients with ICB-responsive metastatic MSS/pMMR-CRC. This pragmatic measure may be used to monitor patients in investigational ICB schedules, enabling early treatment adaptation for unresponsive cases. TRIAL REGISTRATION: ClinicalTrials.gov number, NCT03388190 (02/01/2018).

Systematic review of health-related quality of life (HRQoL) issues associated with gastric cancer: capturing cross-cultural differences.

The treatment landscape for gastric cancer (GC) is constantly evolving with therapies affecting all aspects of health-related quality of life (HRQoL) which need careful monitoring. While there are HRQoL measures designed specifically to capture issues relevant to patients with GC, these might be outdated and only relevant to patients in westernised cultures. This review identifies the patient-reported measures used to assess HRQoL of patients with GC and compares the HRQoL measures used across cultures including East Asia, where GC is more prevalent. We conducted a systematic review of publications between January 2001 and January 2021. A total of 267 papers were identified; the majority (66%) of studies involved patients from East Asian countries. Out of the 24 HRQoL questionnaires captured, the European Organisation for Research and Treatment of Cancer Core Cancer measure (QLQ-C30) was the most widely used (60% of all studies and 62% of those involving patients from East Asian countries), followed by its gastric cancer-specific module (QLQ-STO22, 34% of all studies and 41% from East Asia). Eight questionnaires were developed within East Asian countries and, of the 20 studies including bespoke questions, 16 were from East Asia. There were six qualitative studies. HRQoL issues captured include diarrhoea, constipation, reflux, abdominal pain and abdominal fulness or bloating, difficulty swallowing, restricted eating, and weight loss. Psychosocial issues related to these problems were also assessed. Issues relating to the compatibility of some of the westernised measures within East Asian cultures were highlighted.

Characteristics and fate of patients with rectal cancer not entering a curative-intent treatment pathway: A complete nationwide registry cohort of 3,304 patients.

BACKGROUND: Treatment options for advanced and metastatic rectal cancer have increased during the past decades. However, a considerable proportion of the patients are not eligible for curative treatment, and data on this subset are scarce from a population-based perspective. This study aimed to describe treatment pathways and survival in a national cohort of patients with primary stage IV rectal cancer or stage I-III rectal cancer not eligible for curative treatment. METHODS: A national cohort of all patients reported 2008-2015 to the Norwegian Colorectal Cancer Registry with primary metastatic rectal cancer or who did not undergo curative resections for stage I-III rectal cancer was studied with regard to patient characteristics, treatments, and survival. RESULTS: Of 8291 patients diagnosed with rectal cancer, 3304 (39.9%) were eligible for analysis. The majority (76.8%) had metastatic disease, and 23.2% did not undergo curative resections for other reasons. We identified four main treatment journeys: no tumour-directed treatment, 25.1%; resection of the primary tumour, 44.6%; oncological treatment, 28.4%; and R0 resection of the primary tumour and metastases, 1.9%; these translated into ten different treatment pathways. Survival differed considerably between a median of 5.3 months for M1 disease with non-tumour-directed treatment to a five-year survival of 67% for M1 with R0 resection. CONCLUSION: Almost 40% of all patients with rectal cancer did not enter a curative-intent treatment pathway. The patient journeys and outcomes varied greatly. This large but understudied population warrants further in-depth analyses of treatment efficacy and effects on quality of life.

The survival gap between young and older patients after surgical resection for colorectal cancer remains largely based on early mortality: A EURECCA comparison of four European countries.

BACKGROUND: A decade ago, it was demonstrated that the difference in survival between older patients and younger patients with colorectal cancer (CRC) was mainly due to mortality in the first postoperative year. Over the last few years, improvements - especially in perioperative care - have increased survival. The current research investigates whether a survival gap between younger and older patients with CRC still exists on a national level in four European countries. METHODS: Population-based data from Belgium, the Netherlands, Norway, and Sweden were collected from patients that underwent surgical resection for primary stage I-III CRC between 2007 and 2016. Relative survival and conditional relative survival (CS), with the condition of surviving the first postoperative year, were calculated for colon and rectal cancer separately, stratified for country and age category (<65, 65-75, ≥75 years). In addition, relative excess risk of death (RER) was estimated, and one-year excess mortality was calculated. RESULTS: Data of 206,024 patients were analyzed. In general, compared to patients <65 years, patients ≥75 years had a worse survival during the first year after surgery, which was most pronounced in Belgium (RER colon cancer 2.5 [95% confidence interval (CI) 2.3-2.8] and RER rectal cancer 2.6 [95% CI 2.3-2.9]). After surviving the first year, CS was mostly not statistically different between patients <65 years and patients ≥75 years with stage I-II, with the exception of stage II colon cancer in Belgium. However, CS remained worse in the largest part of the patients ≥75 years with stage III colon or rectal cancer (except for rectal cancer in Norway). CONCLUSIONS: Although differences exist between the countries, the survival gap between young and older patients is based mainly on early mortality and remains only for stage III disease after surviving the first year.

Quality of life and late toxicity after short-course radiotherapy followed by chemotherapy or chemoradiotherapy for locally advanced rectal cancer - The RAPIDO trial.

BACKGROUND AND PURPOSE: The RAPIDO trial demonstrated a decrease in disease-related treatment failure (DrTF) and an increase in pathological complete responses (pCR) in locally advanced rectal cancer (LARC) patients receiving total neoadjuvant treatment (TNT) compared to conventional chemoradiotherapy. This study examines health-related quality of life (HRQL), bowel function, and late toxicity in patients in the trial. MATERIALS AND METHODS: Patients were randomized between short-course radiotherapy followed by pre-operative chemotherapy (EXP), or chemoradiotherapy and optional post-operative chemotherapy (STD). The STD group was divided into patients who did (STD+) and did not (STD-) receive post-operative chemotherapy. Three years after surgery patients received HRQL (EORTC QLQ-C30, QLQ-CR29 and QLQ-CIPN20) and LARS questionnaires. Patients who experienced a DrTF event before the toxicity assessments (6, 12, 24, or 36 months) were excluded from analyses. RESULTS: Of 574 eligible patients, 495 questionnaires were returned (86%) and 453 analyzed (79% completed within time limits). No significant differences were observed between the groups regarding QLQ-C30, QLQ-CR29 or LARS scores. Sensory-related symptoms occurred significantly more often in the EXP group compared to all STD patients, but not compared to STD+ patients. Any toxicity of any grade and grade ≥ 3 toxicity was comparable between the EXP and STD groups at all time-points. Neurotoxicity grade 1-2 occurred significantly more often in the EXP and STD+ group at all time-points compared to the STD- group. CONCLUSION: The results demonstrate that TNT for LARC, yielding improved DrTF and pCRs, does not compromise HRQL, bowel functional or results in more grade ≥3 toxicity compared to standard chemoradiotherapy at three years after surgery in DrTF-free patients.

A Machine-Learning-Based Bibliometric Analysis of the Scientific Literature on Anal Cancer.

Squamous-cell carcinoma of the anus (ASCC) is a rare disease. Barriers have been encountered to conduct clinical and translational research in this setting. Despite this, ASCC has been a prime example of collaboration amongst researchers. We performed a bibliometric analysis of ASCC-related literature of the last 20 years, exploring common patterns in research, tracking collaboration and identifying gaps. The electronic Scopus database was searched using the keywords "anal cancer", to include manuscripts published in English, between 2000 and 2020. Data analysis was performed using R-Studio 0.98.1091 software. A machine-learning bibliometric method was applied. The bibliometrix R package was used. A total of 2322 scientific documents was found. The average annual growth rate in publication was around 40% during 2000-2020. The five most productive countries were United States of America (USA), United Kingdom (UK), France, Italy and Australia. The USA and UK had the greatest link strength of international collaboration (22.6% and 19.0%). Two main clusters of keywords for published research were identified: (a) prevention and screening and (b) overall management. Emerging topics included imaging, biomarkers and patient-reported outcomes. Further efforts are required to increase collaboration and funding to sustain future research in the setting of ASCC.

Compliance with recommended cancer patient pathway timeframes and choice of treatment differed by cancer type and place of residence among cancer patients in Norway in 2015-2016.

BACKGROUND: Cancer patient pathways (CPPs) were implemented in Norway to reduce unnecessary waiting times, regional variations, and to increase the predictability of cancer care for the patients. This study aimed to determine if 70% of cancer patients started treatment within the recommended time frames, and to identify potential delays. METHODS: Patients registered with a colorectal, lung, breast, or prostate cancer diagnosis at the Cancer Registry of Norway in 2015-2016 were linked with the Norwegian Patient Registry and Statistics Norway. Adjusting for sociodemographic variables, multivariable quantile (median) regressions were used to examine the association between place of residence and median time to start of examination, treatment decision, and start of treatment. RESULTS: The study included 20 668 patients. The proportions of patients who went through the CPP within the recommended time frames were highest among colon (84%) and breast (76%) cancer patients who underwent surgery and lung cancer patients who started systemic anticancer treatment (76%), and lowest for prostate cancer patients who underwent surgery (43%). The time from treatment decision to start of treatment was the main source of delay for all cancers. Travelling outside the resident health trust prolonged waiting time and was associated with a reduced odds of receiving surgery and radiotherapy for lung and rectal cancer patients, respectively. CONCLUSIONS: Achievement of national recommendations of the CCP times differed by cancer type and treatment. Identified bottlenecks in the pathway should be targeted to decrease waiting times. Further, CPP guidelines should be re-examined to determine their ongoing relevance.

Sex hormones and sperm parameters after adjuvant oxaliplatin-based treatment for colorectal cancer.

BACKGROUND: The incidence of colorectal cancer (CRC) in individuals of fertile age is increasing. Oxaliplatin is a cornerstone treatment in the adjuvant setting for stage III and high-risk stage II CRC. Limited data exist on possible side effects of oxaliplatin on fertility and gonadal function. More data is needed to guide possible fertility preservation procedures and aid evidence-based fertility counselling. PATIENTS AND METHODS: The aim of this study (EudraCT2006-002832-10) was to prospectively investigate sex hormones and sperm parameters after oxaliplatin-based adjuvant chemotherapy to clarify the risk of infertility and hypogonadism. Twenty males aged ≤55 years and 16 females aged ≤40 years were recruited from five hospitals in the Nordic countries. All had undergone radical surgery due to CRC and were given adjuvant oxaliplatin in combination with 5-fluorouracil. Measurement of luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone, sex hormone binding globulin (SHBG) and semen analysis were done in males, while LH, FSH and oestradiol were measured in females. Measurements were done prior to chemotherapy, after completion of adjuvant treatment and at follow-up 1 and up to 5 years after end of treatment. RESULTS: FSH and testosterone levels increased in males after chemotherapy treatment but were restored at follow-up. No patients developed hypogonadism. There was a trend towards a decrease in sperm concentration during treatment (p = 0.063). When comparing sperm concentration and rapid progressive motility of sperms prior to chemotherapy and at follow-up, there were no differences, and no patients became permanently azoospermic by treatment. No distinct altering of gonadal function could be observed in females. CONCLUSIONS: Oxaliplatin in combination with 5-fluorouracil seems to induce transient decrease in sperm concentration with recovery and a minor transient increase in FSH in males. No distinct altering of gonadal function was observed in females. The risk of infertility and hypogonadism in males and females after adjuvant oxaliplatin-based chemotherapy seems low.

E-cadherin is a robust prognostic biomarker in colorectal cancer and low expression is associated with sensitivity to inhibitors of topoisomerase, aurora, and HSP90 in preclinical models.

Cell-cell and cell-matrix adhesion proteins that have been implicated in colorectal epithelial integrity and epithelial-to-mesenchymal transition could be robust prognostic and potential predictive biomarkers for standard and novel therapies. We analyzed in situ protein expression of E-cadherin (ECAD), integrin ß4 (ITGB4), zonula occludens 1 (ZO-1), and cytokeratins in a single-hospital series of Norwegian patients with colorectal cancer (CRC) stages I-IV (n = 922) using multiplex fluorescence-based immunohistochemistry (mfIHC) on tissue microarrays. Pharmacoproteomic associations were explored in 35 CRC cell lines annotated with drug sensitivity data on > 400 approved and investigational drugs. ECAD, ITGB4, and ZO-1 were positively associated with survival, while cytokeratins were negatively associated with survival. Only ECAD showed independent prognostic value in multivariable Cox models. Clinical and molecular associations for ECAD were technically validated on a different mfIHC platform, and the prognostic value was validated in another Norwegian series (n = 798). In preclinical models, low and high ECAD expression differentially associated with sensitivity to topoisomerase, aurora, and HSP90 inhibitors, and EGFR inhibitors. E-cadherin protein expression is a robust prognostic biomarker with potential clinical utility in CRC.

Survival Trends of Right- and Left-Sided Colon Cancer across Four Decades: A Norwegian Population-Based Study.

BACKGROUND: Patients with right-sided colon cancer (RCC) and left-sided colon cancer (LCC) differ clinically and molecularly. The main objective was to investigate stage-stratified survival and recurrence of RCC and LCC across four 10-year periods. METHODS: Patients diagnosed from 1977 to 2016 with colon adenocarcinoma were included from the Cancer Registry of Norway. Primary tumor location (PTL) was defined as RCC if proximal and LCC if distal to the splenic flexure. Multivariable regressions were used to estimate HRs for overall survival (OS), recurrence-free survival (RFS), survival after recurrence (SAR), and excess HRs (eHR) for relative survival (RS). RESULTS: 72,224 patients were eligible for analyses [55.1% (n = 39,769/72,224) had RCC]. In 1977 to 1986, there was no difference between LCC and RCC in OS [HR, 1.01; 95% confidence interval (CI), 0.97-1.06; P = 0.581] or RS (eHR, 0.96; 95% CI, 0.90-1.02; P = 0.179). In 2007 to 2016, LCC had significantly better OS (HR, 0.84; 95% CI, 0.80-0.87; P < 0.001) and RS (eHR, 0.76; 95% CI, 0.72-0.81; P < 0.001) compared with RCC. The gradually diverging and significantly favorable prognosis for LCC was evident for distant disease across all time periods and for regional disease from 2007 onward. There was no difference in RFS between LCC and RCC in patients less than 75 years during 2007 to 2016 (HR, 0.99; 95% CI, 0.91-1.08; P = 0.819); however, SAR was significantly better for LCC (HR, 0.61; 95% CI, 0.53-0.71; P < 0.001). CONCLUSIONS: A gradually diverging and increasingly favorable prognosis was observed for patients with LCC with advanced disease over the past four decades. IMPACT: Current PTL survival disparities stress the need for further exploring targetable molecular subgroups across and within different PTLs to further improve patient outcomes.

Increased sensitivity to SMAC mimetic LCL161 identified by longitudinal ex vivo pharmacogenomics of recurrent, KRAS mutated rectal cancer liver metastases.

Tumor heterogeneity is a primary cause of treatment failure. However, changes in drug sensitivity over time are not well mapped in cancer. Patient-derived organoids (PDOs) may predict clinical drug responses ex vivo and offer an opportunity to evaluate novel treatment strategies in a personalized fashion. Here we have evaluated spatio-temporal functional and molecular dynamics of five PDO models established after hepatic re-resections and neoadjuvant combination chemotherapies in a patient with microsatellite stable and KRAS mutated metastatic rectal cancer. Histopathological differentiation phenotypes of the PDOs corresponded with the liver metastases, and ex vivo drug sensitivities generally reflected clinical responses and selection pressure, assessed in comparison to a reference data set of PDOs from metastatic colorectal cancers. PDOs from the initial versus the two recurrent metastatic settings showed heterogeneous cell morphologies, protein marker expression, and drug sensitivities. Exploratory analyses of a drug screen library of 33 investigational anticancer agents showed the strongest ex vivo sensitivity to the SMAC mimetic LCL161 in PDOs of recurrent disease compared to those of the initial metastasis. Functional analyses confirmed target inhibition and apoptosis induction in the LCL161 sensitive PDOs from the recurrent metastases. Gene expression analyses indicated an association between LCL161 sensitivity and tumor necrosis factor alpha signaling and RIPK1 gene expression. In conclusion, LCL161 was identified as a possible experimental therapy of a metastatic rectal cancer that relapsed after hepatic resection and standard systemic treatment.

De novo transcriptomic subtyping of colorectal cancer liver metastases in the context of tumor heterogeneity.

BACKGROUND: Gene expression-based subtyping has the potential to form a new paradigm for stratified treatment of colorectal cancer. However, current frameworks are based on the transcriptomic profiles of primary tumors, and metastatic heterogeneity is a challenge. Here we aimed to develop a de novo metastasis-oriented framework. METHODS: In total, 829 transcriptomic profiles from patients with colorectal cancer were analyzed, including primary tumors, liver metastases, and non-malignant liver samples. High-resolution microarray gene expression profiling was performed of 283 liver metastases from 171 patients treated by hepatic resection, including multiregional and/or multi-metastatic samples from each of 47 patients. A single randomly selected liver metastasis sample from each patient was used for unsupervised subtype discovery by nonnegative matrix factorization, and a random forest prediction model was trained to classify multi-metastatic samples, as well as liver metastases from two independent series of 308 additional patients. RESULTS: Initial comparisons with non-malignant liver samples and primary colorectal tumors showed a highly variable degree of influence from the liver microenvironment in metastases, which contributed to inter-metastatic transcriptomic heterogeneity, but did not define subtype distinctions. The de novo liver metastasis subtype (LMS) framework recapitulated the main distinction between epithelial-like and mesenchymal-like tumors, with a strong immune and stromal component only in the latter. We also identified biologically distinct epithelial-like subtypes originating from different progenitor cell types. LMS1 metastases had several transcriptomic features of cancer aggressiveness, including secretory progenitor cell origin, oncogenic addictions, and microsatellite instability in a microsatellite stable background, as well as frequent RAS/TP53 co-mutations. The poor-prognostic association of LMS1 metastases was independent of mutation status, clinicopathological variables, and current subtyping frameworks (consensus molecular subtypes and colorectal cancer intrinsic subtypes). LMS1 was also the least heterogeneous subtype in comparisons of multiple metastases per patient, and tumor heterogeneity did not confound the prognostic value of LMS1. CONCLUSIONS: We report the first large study of multi-metastatic gene expression profiling of colorectal cancer. The new metastasis-oriented subtyping framework showed potential for clinically relevant transcriptomic classification in the context of metastatic heterogeneity, and an LMS1 mini-classifier was constructed to facilitate prognostic stratification and further clinical testing.

Factors associated with emergency-onset diagnosis, time to treatment and type of treatment in colorectal cancer patients in Norway.

BACKGROUND: International differences in survival among colorectal cancer (CRC) patients may partly be explained by differences in emergency presentations (EP), waiting times and access to treatment. METHODS: CRC patients registered in 2015-2016 at the Cancer Registry of Norway were linked with the Norwegian Patient Registry and Statistics Norway. Multivariable logistic regressions analysed the odds of an EP and access to surgery, radiotherapy and systemic anticancer treatment (SACT). Multivariable quantile regression analysed time from diagnosis to treatment. RESULTS: Of 8216 CRC patients 29.2% had an EP before diagnosis, of which 81.4% were admitted to hospital with a malignancy-related condition. Higher age, more advanced stage, more comorbidities and colon cancer were associated with increased odds of an EP (p < 0.001). One-year mortality was 87% higher among EP patients (HR=1.87, 95%CI:1.75-2.02). Being married or high income was associated with 30% reduced odds of an EP (p < 0.001). Older age was significantly associated with increased waiting time to treatment (p < 0.001). Region of residence was significantly associated with waiting time and access to treatment (p < 0.001). Male (OR = 1.30, 95%CI:1.03,1.64) or married (OR = 1.39, 95%CI:1.09,1.77) colon cancer patients had an increased odds of SACT. High income rectal cancer patients had an increased odds (OR = 1.48, 95%CI:1.03,2.13) of surgery. CONCLUSION: Patients who were older, with advanced disease or more comorbidities were more likely to have an emergency-onset diagnosis and less likely to receive treatment. Income was not associated with waiting time or access to treatment among CRC patients, but was associated with the likelihood of surgery among rectal cancer patients.

One-year excess mortality and treatment in surgically treated patients with colorectal cancer: A EURECCA European comparison.

BACKGROUND: Mortality in the first postoperative year represents an accurate reflection of the perioperative risk after colorectal cancer surgery. This research compares one-year mortality after surgery divided into three age-categories (18-64, 65-74, ≥75 years), focusing on time trends and comparing treatment strategies. MATERIAL: Population-based data of all patients diagnosed and treated surgically for stage I-III primary colorectal cancer from 2007 to 2016, were collected from Belgium, the Netherlands, Norway, and Sweden. Stratified for age-category and stage, treatment was evaluated, and 30-day, one-year and one-year excess mortality were calculated for colon and rectal cancer separately. Results were evaluated over two-year time periods. RESULTS: Data of 206,024 patients were analysed. Postoperative 30-day and one-year mortality reduced significantly over time in all countries and age-categories. Within the oldest age category, in 2015-2016, one-year excess mortality varied from 9% in Belgium to 4% in Sweden for colon cancer and, from 9% in Belgium to 3% in the other countries for rectal cancer. With increasing age, patients were less likely to receive additional therapy besides surgery. In Belgium, colon cancer patients were more often treated with adjuvant chemotherapy (p < 0.001). For neoadjuvant treatment of rectal cancer, patients in Belgium and Norway were mostly treated with chemoradiotherapy. In the Netherlands and Sweden, radiotherapy alone was preferred (p < 0.001). CONCLUSIONS: Despite improvement over time in all countries and age-categories, substantial variation exists in one-year postoperative mortality. Differences in one-year excess postoperative mortality could be due to differences in treatment strategies, highlighting the consequences of under- and over-treatment on cancer survival.