Histopathological tumour microenvironment score independently predicts outcome in primary operable colorectal cancer

Colorectal cancer (CRC) is a heterogenous malignancy and research is focused on identifying novel ways to subtype patients. In this study, a novel classification system, tumour microenvironment score (TMS), was devised based on Klintrup-Mäkinen grade (KMG), tumour stroma percentage (TSP), and tumour budding. TMS was performed using a haematoxylin and eosin (H&E)-stained section from retrospective CRC discovery and validation cohorts (n = 1,030, n = 787). TMS0 patients had high KMG, TMS1 were low for KMG, TSP, and budding, TMS2 were high for budding, or TSP and TMS3 were high for TSP and budding. Scores were assessed for association with survival and clinicopathological characteristics. Mutational landscaping and Templated Oligo-Sequencing (TempO-Seq) profiling were performed to establish differences in the underlying biology of TMS. TMS was independently prognostic in both cohorts (p < 0.001, p < 0.001), with TMS3 predictive of the shortest survival times. TMS3 was associated with adverse clinical features including sidedness, local and distant recurrence, higher T stage, higher N stage, and presence of margin involvement. Gene set enrichment analysis of TempO-Seq data showed higher expression of genes associated with hallmarks of cancer pathways including epithelial to mesenchymal transition (p < 0.001), IL2 STAT5 signalling (p = 0.007), and angiogenesis (p = 0.017) in TMS3. Additionally, enrichment of immunosuppressive immune signatures was associated with TMS3 classification. In conclusion, TMS represents a novel and clinically relevant method for subtyping CRC patients from a single H&E-stained tumour section.

A retrospective cohort study evaluating pregnancy outcomes in women with MIDD

AIMS

The most common pathogenic mitochondrial mutation associated with mitochondrial disease is m.3243A>G. Increased obstetric complications, such as spontaneous abortion, gestational diabetes (GDM), preterm delivery, and preeclampsia, have been reported in women carrying this mutation. We aimed to determine the fetal and maternal outcomes in pregnant women with mitochondrial disease.

METHODS

We retrospectively studied the obstetric and perinatal outcomes in 88 pregnancies of 26 women with genetically confirmed mitochondrial disease (m.3243A>G in the MTTL1 gene (n = 25); m.12258C>A in the MT-TS2 gene (n = 1)). Outcomes included pregnancy related complications, mode of delivery, gestational age at delivery and birthweight.

RESULTS

Mean heteroplasmy rate was 18%. The miscarriage rate was higher than background at 25%. 21 pregnancies (24%) were complicated by GDM; 9 pregnancies (13.6%) had a preterm delivery and 2 of them (3%) an extreme premature delivery < 32 weeks. One woman had preeclampsia and one had a postpartum hemorrhage. The caesarean section (CS) rate was 20%. For every unit increase in maternal heteroplasmy levels there was a 26% increased risk of undergoing an assisted operative vaginal delivery (OR 1.26, 95% CI 1.04-1.53, P = 0.002, Bonferroni corrected P = 0.005) and an 18% increased risk of undergoing a CS (OR 1.18, 95% CI 1.01-1.39, P = 0.01, Bonferroni corrected P = 0.03) compared to a spontaneous vaginal delivery. There was a statistical significant correlation between maternal and offspring heteroplasmy levels. Spearman correlation rho = 0.96, 95% CI 0.78-0.99, P = 0.0002.

CONCLUSION

Women with mitochondrial disease appear to have more frequent obstetric complications including miscarriage and GDM. Pre-pregnancy diagnosis of m.3243A>G will enable the counseling of women and increase awareness of possible obstetric complications.

JAK/STAT3 represents a therapeutic target for colorectal cancer patients with stromal-rich tumors

Colorectal cancer (CRC) is a heterogenous malignancy underpinned by dysregulation of cellular signaling pathways. Previous literature has implicated aberrant JAK/STAT3 signal transduction in the development and progression of solid tumors. In this study we investigate the effectiveness of inhibiting JAK/STAT3 in diverse CRC models, establish in which contexts high pathway expression is prognostic and perform in depth analysis underlying phenotypes. In this study we investigated the use of JAK inhibitors for anti-cancer activity in CRC cell lines, mouse model organoids and patient-derived organoids. Immunohistochemical staining of the TransSCOT clinical trial cohort, and 2 independent large retrospective CRC patient cohorts was performed to assess the prognostic value of JAK/STAT3 expression. We performed mutational profiling, bulk RNASeq and NanoString GeoMx® spatial transcriptomics to unravel the underlying biology of aberrant signaling. Inhibition of signal transduction with JAK1/2 but not JAK2/3 inhibitors reduced cell viability in CRC cell lines, mouse, and patient derived organoids (PDOs). In PDOs, reduced Ki67 expression was observed post-treatment. A highly significant association between high JAK/STAT3 expression within tumor cells and reduced cancer-specific survival in patients with high stromal invasion (TSPhigh) was identified across 3 independent CRC patient cohorts, including the TrasnSCOT clinical trial cohort. Patients with high phosphorylated STAT3 (pSTAT3) within the TSPhigh group had higher influx of CD66b + cells and higher tumoral expression of PDL1. Bulk RNAseq of full section tumors showed enrichment of NFκB signaling and hypoxia in these cases. Spatial deconvolution through GeoMx® demonstrated higher expression of checkpoint and hypoxia-associated genes in the tumor (pan-cytokeratin positive) regions, and reduced lymphocyte receptor signaling in the TME (pan-cytokeratin- and αSMA-) and αSMA (pan-cytokeratin- and αSMA +) areas. Non-classical fibroblast signatures were detected across αSMA + regions in cases with high pSTAT3. Therefore, in this study we have shown that inhibition of JAK/STAT3 represents a promising therapeutic strategy for patients with stromal-rich CRC tumors. High expression of JAK/STAT3 proteins within both tumor and stromal cells predicts poor outcomes in CRC, and aberrant signaling is associated with distinct spatially-dependant differential gene expression.

Spatial transcriptomic analysis of tumour with high and low CAIX expression in TNBC tissue samples using GeoMx™ RNA assay

PURPOSE

Prognostic significance and gene signatures associated with carbonic anhydrase IX (CAIX) was investigated in triple negative breast cancer (TNBC) patients.

METHODS

Immunohistochemistry (IHC) for CAIX was performed in tissue microarrays (TMAs) of 136 TNBC patients. In a subset of 52 patients Digital Spatial Profiler (DSP) was performed in tumour (pan-cytokeratin+) and stroma (pan-cytokeratin-). Differentially expressed genes (DEGs) with P<0.05 and and log2 fold change (FC)>(±0.25 and ±0.3, for tumour and stromal compartment, respectively) were identified. Four genes were validated at the protein level.

RESULT

Cytoplasmic CAIX expression was independently associated with poor recurrence free survival in TNBC patients [hazard ratio (HR)=6.59, 95% confidence interval (CI): 1.47-29.58, P=0.014]. DEG analysis identified 4 up-regulated genes (CD68, HIF1A, pan-melanocyte, and VSIR) in the tumour region and 9 down-regulated genes in the stromal region (CD86, CD3E, MS4A1, BCL2, CCL5, NKG7, PTPRC, CD27, and FAS) when low versus high CAIX expression was explored. Employing IHC, high CD68 and HIF-1α was associated with poorer prognosis and high BCL2 and CD3 was associated with good prognosis.

CONCLUSIONS

DSP technology identified DEGs in TNBC. Selected genes validated by IHC showed involvement of CD3 and BCL2 expression within stroma and HIF-1α, and CD68 expression within tumour. However, further functional analysis is warranted.

Multiplex analysis of intratumoural immune infiltrate and prognosis in patients with stage II-III colorectal cancer from the SCOT and QUASAR 2 trials: a retrospective analysis

BACKGROUND

Tumour-infiltrating CD8+ cytotoxic T cells confer favourable prognosis in colorectal cancer. The added prognostic value of other infiltrating immune cells is unclear and so we sought to investigate their prognostic value in two large clinical trial cohorts.

METHODS

We used multiplex immunofluorescent staining of tissue microarrays to assess the densities of CD8+, CD20+, FoxP3+, and CD68+ cells in the intraepithelial and intrastromal compartments from tumour samples of patients with stage II-III colorectal cancer from the SCOT trial (ISRCTN59757862), which examined 3 months versus 6 months of adjuvant oxaliplatin-based chemotherapy, and from the QUASAR 2 trial (ISRCTN45133151), which compared adjuvant capecitabine with or without bevacizumab. Both trials included patients aged 18 years or older with an Eastern Cooperative Oncology Group performance status of 0-1. Immune marker predictors were analysed by multiple regression, and the prognostic and predictive values of markers for colorectal cancer recurrence-free interval by Cox regression were assessed using the SCOT cohort for discovery and QUASAR 2 cohort for validation.

FINDINGS

After exclusion of cases without tissue microarrays and with technical failures, and following quality control, we included 2340 cases from the SCOT trial and 1069 from the QUASAR 2 trial in our analysis. Univariable analysis of associations with recurrence-free interval in cases from the SCOT trial showed a strong prognostic value of intraepithelial CD8 (CD8IE) as a continuous variable (hazard ratio [HR] for 75th vs 25th percentile [75vs25] 0·73 [95% CI 0·68-0·79], p=2·5 × 10-16), and of intrastromal FoxP3 (FoxP3IS; 0·71 [0·64-0·78], p=1·5 × 10-13) but not as strongly in the epithelium (FoxP3IE; 0·89 [0·84-0·96], p=1·5 × 10-4). Associations of other markers with recurrence-free interval were moderate. CD8IE and FoxP3IS retained independent prognostic value in bivariable and multivariable analysis, and, compared with either marker alone, a composite marker including both markers (CD8IE-FoxP3IS) was superior when assessed as a continuous variable (adjusted [a]HR75 vs 25 0·70 [95% CI 0·63-0·78], p=5·1 × 10-11) and when categorised into low, intermediate, and high density groups using previously published cutpoints (aHR for intermediate vs high 1·68 [95% CI 1·29-2·20], p=1·3 × 10-4; low vs high 2·58 [1·91-3·49], p=7·9 × 10-10), with performance similar to the gold-standard Immunoscore. The prognostic value of CD8IE-FoxP3IS was confirmed in cases from the QUASAR 2 trial, both as a continuous variable (aHR75 vs 25 0·84 [95% CI 0·73-0·96], p=0·012) and as a categorical variable for low versus high density (aHR 1·80 [95% CI 1·17-2·75], p=0·0071) but not for intermediate versus high (1·30 [0·89-1·88], p=0·17).

INTERPRETATION

Combined evaluation of CD8IE and FoxP3IS could help to refine risk stratification in colorectal cancer. Investigation of FoxP3IS cells as an immunotherapy target in colorectal cancer might be merited.

FUNDING

Medical Research Council, National Institute for Health Research, Cancer Research UK, Swedish Cancer Society, Roche, and Promedica Foundation.

Radiation-induced changes in gene expression in rectal cancer specimens

PURPOSE

The standard-of-care for locally advanced rectal cancer is radiotherapy-based neoadjuvant therapy followed by surgical resection. This article reviews the evidence of molecular changes at the transcriptome level induced through radiotherapy in rectal cancer.

METHODS

The PubMed search "(radiation OR radiotherapy) cancer (transcriptome OR "gene expression") rectal" was used. The studies taken forward utilised gene-expression data on both pre-treatment and post-treatment rectal adenocarcinoma biospecimens from patients treated with RT-based neoadjuvant strategies.

RESULTS

Twelve publications met the review criteria. There was variation in approaches in terms of design, patient population, cohort size, timing of the post-radiotherapy sampling and method of measuring gene expression. Most of the post-treatment biospecimen retrievals were at resection. The literature indicates a broad upregulation of immune activity through radiotherapy using gene-expression data.

CONCLUSION

Future studies would benefit from standardised prospective approaches to sampling to enable the inclusion of timepoints relevant to the tumour and immune response.

The Complexity of Shapes: How the Circularity of Tumor Nodules Affects Prognosis in Colorectal Cancer

The current stratification of tumor nodules in colorectal cancer (CRC) staging is subjective and leads to high interobserver variability. In this study, the objective assessment of the shape of lymph node metastases (LNMs), extranodal extension (ENE), and tumor deposits (TDs) was correlated with outcomes. A test cohort and a validation cohort were included from 2 different institutions. The test cohort consisted of 190 cases of stage III CRC. Slides with LNMs and TDs were annotated and processed using a segmentation algorithm to determine their shape. The complexity ratio was calculated for every shape and correlated with outcomes. A cohort of 160 stage III CRC cases was used to validate findings. TDs showed significantly more complex shapes than LNMs with ENE, which were more complex than LNMs without ENE (P < .001). In the test cohort, patients with the highest sum of complexity ratios had significantly lower disease-free survival (P < .01). When only the nodule with the highest complexity was considered, this effect was even stronger (P < .001). This maximum complexity ratio per patient was identified as an independent prognostic factor in the multivariate analysis (hazard ratio, 2.47; P < .05). The trends in the validation cohort confirmed the results. More complex nodules in stage III CRC were correlated with significantly worse disease-free survival, even if only based on the most complex nodule. These results suggest that more complex nodules reflect more invasive tumor biology. As most of the more complex nodules were diagnosed as TDs, we suggest providing a more prominent role for TDs in the nodal stage and include an objective complexity measure in their definition.

WNT Signalling Promotes NF-κB Activation and Drug Resistance in KRAS-Mutant Colorectal Cancer

Approximately 40% of colorectal cancer (CRC) cases are characterized by KRAS mutations, rendering them insensitive to most CRC therapies. While the reasons for this resistance remain incompletely understood, one key aspect is genetic complexity: in CRC, oncogenic KRAS is most commonly paired with mutations that alter WNT and P53 activities ("RAP"). Here, we demonstrate that elevated WNT activity upregulates canonical (NF-κB) signalling in both Drosophila and human RAS mutant tumours. This upregulation required Toll-1 and Toll-9 and resulted in reduced efficacy of RAS pathway targeted drugs such as the MEK inhibitor trametinib. Inhibiting WNT activity pharmacologically significantly suppressed trametinib resistance in RAP tumours and more genetically complex RAP-containing 'patient avatar' models. WNT/MEK drug inhibitor combinations were further improved by targeting brm, shg, ago, rhoGAPp190 and upf1, highlighting these genes as candidate biomarkers for patients sensitive to this duel approach. These findings shed light on how genetic complexity impacts drug resistance and proposes a therapeutic strategy to reverse this resistance.

Posterior stabilised total knee arthroplasty is associated with improved post-operative knee specific function, health related quality of life and greater satisfaction when compared to cruciate retaining protheses

PURPOSE

To assess whether there were differences in knee specific function, health related quality of life (HRQoL), and satisfaction between patients with a cruciate retaining (CR) or a posterior stabilised (PS) total knee arthroplasty (TKA) at 1 and 2 years postoperatively.

METHODS

A retrospective review of TKA (CR and PS) patients from a prospectively collected arthroplasty database. Patient demographics, body mass index and ASA grade, Oxford knee score (OKS) and EuroQol 5-dimension (EQ-5D) 3-level, which was used to assess HRQoL, were collected preoperatively and 1 year and 2 years postoperatively. Regression was used to adjust for confounding factors.

RESULTS

The sample included 3122 TKA, of which 1009 (32.3%) were CR and 2112 (67.7%) were PS. The PS group were more likely to be female (odd ratio (OR) 1.26, p = 0.003) and undergo resurfacing of the patella (OR 6.63, p < 0.001). There was a significantly greater improvement in the 1 year OKS in the PS group (mean difference (MD) 0.9, p = 0.016). The PS TKA was independently associated with a greater 1 year (MD 1.1, 95% CI 0.4 to 1.9, p = 0.001) and 2 years (MD 0.8, p = 0.037) post-operative improvements in OKS. PS TKA was also independently associated with a greater 1 year (MD 0.021, p = 0.024) and 2 years (MD 0.022, p = 0.025) post-operative and change in EQ-5D utility compared to the CR group. The PS group was more likely to be satisfied with their outcome at 1 year (OR 1.75, p < 0.001) and at 2 years (OR 1.38, p = 0.001) when adjusting for confounders.

CONCLUSION

PS TKA was associated with a better knee specific function and HRQoL when compared to CR, but the clinical significance of this is not clear. However, the PS group was more likely to be satisfied with their outcome compared to the CR group.

Improving radiotherapy in immunosuppressive microenvironments by targeting complement receptor C5aR1

An immunosuppressive microenvironment causes poor tumor T cell infiltration and is associated with reduced patient overall survival in colorectal cancer. How to improve treatment responses in these tumors is still a challenge. Using an integrated screening approach to identify cancer-specific vulnerabilities, we identified complement receptor C5aR1 as a druggable target, which when inhibited improved radiotherapy, even in tumors displaying immunosuppressive features and poor CD8+ T cell infiltration. While C5aR1 is well-known for its role in the immune compartment, we found that C5aR1 is also robustly expressed on malignant epithelial cells, highlighting potential tumor cell-specific functions. C5aR1 targeting resulted in increased NF-κB-dependent apoptosis specifically in tumors and not normal tissues, indicating that, in malignant cells, C5aR1 primarily regulated cell fate. Collectively, these data revealed that increased complement gene expression is part of the stress response mounted by irradiated tumors and that targeting C5aR1 could improve radiotherapy, even in tumors displaying immunosuppressive features.

Accounting for intensity variation in image analysis of large-scale multiplexed clinical trial datasets

Multiplex immunofluorescence (mIF) imaging can provide comprehensive quantitative and spatial information for multiple immune markers for tumour immunoprofiling. However, application at scale to clinical trial samples sourced from multiple institutions is challenging due to pre-analytical heterogeneity. This study reports an analytical approach to the largest multi-parameter immunoprofiling study of clinical trial samples to date. We analysed 12,592 tissue microarray (TMA) spots from 3,545 colorectal cancers sourced from more than 240 institutions in two clinical trials (QUASAR 2 and SCOT) stained for CD4, CD8, CD20, CD68, FoxP3, pan-cytokeratin, and DAPI by mIF. TMA slides were multi-spectrally imaged and analysed by cell-based and pixel-based marker analysis. We developed an adaptive thresholding method to account for inter- and intra-slide intensity variation in TMA analysis. Applying this method effectively ameliorated inter- and intra-slide intensity variation improving the image analysis results compared with methods using a single global threshold. Correlation of CD8 data derived by our mIF analysis approach with single-plex chromogenic immunohistochemistry CD8 data derived from subsequent sections indicates the validity of our method (Spearman's rank correlation coefficients ρ between 0.63 and 0.66, p ≪ 0.01) as compared with the current gold standard analysis approach. Evaluation of correlation between cell-based and pixel-based analysis results confirms equivalency (ρ > 0.8, p ≪ 0.01, except for CD20 in the epithelial region) of both analytical approaches. These data suggest that our adaptive thresholding approach can enable analysis of mIF-stained clinical trial TMA datasets by digital pathology at scale for precision immunoprofiling.

β-Catenin Drives Butyrophilin-like Molecule Loss and γδ T-cell Exclusion in Colon Cancer

Intraepithelial lymphocytes (IEL) expressing γδ T-cell receptors (γδTCR) play key roles in elimination of colon cancer. However, the precise mechanisms by which progressing cancer cells evade immunosurveillance by these innate T cells are unknown. Here, we investigated how loss of the Apc tumor suppressor in gut tissue could enable nascent cancer cells to escape immunosurveillance by cytotoxic γδIELs. In contrast with healthy intestinal or colonic tissue, we found that γδIELs were largely absent from the microenvironment of both mouse and human tumors, and that butyrophilin-like (BTNL) molecules, which can critically regulate γδIEL through direct γδTCR interactions, were also downregulated in tumors. We then demonstrated that β-catenin activation through loss of Apc rapidly suppressed expression of the mRNA encoding the HNF4A and HNF4G transcription factors, preventing their binding to promoter regions of Btnl genes. Reexpression of BTNL1 and BTNL6 in cancer cells increased γδIEL survival and activation in coculture assays but failed to augment their cancer-killing ability in vitro or their recruitment to orthotopic tumors. However, inhibition of β-catenin signaling via genetic deletion of Bcl9/Bcl9L in either Apc-deficient or mutant β-catenin mouse models restored Hnf4a, Hnf4g, and Btnl gene expression and γδ T-cell infiltration into tumors. These observations highlight an immune-evasion mechanism specific to WNT-driven colon cancer cells that disrupts γδIEL immunosurveillance and furthers cancer progression.

Metabolic profiling stratifies colorectal cancer and reveals adenosylhomocysteinase as a therapeutic target

The genomic landscape of colorectal cancer (CRC) is shaped by inactivating mutations in tumour suppressors such as APC, and oncogenic mutations such as mutant KRAS. Here we used genetically engineered mouse models, and multimodal mass spectrometry-based metabolomics to study the impact of common genetic drivers of CRC on the metabolic landscape of the intestine. We show that untargeted metabolic profiling can be applied to stratify intestinal tissues according to underlying genetic alterations, and use mass spectrometry imaging to identify tumour, stromal and normal adjacent tissues. By identifying ions that drive variation between normal and transformed tissues, we found dysregulation of the methionine cycle to be a hallmark of APC-deficient CRC. Loss of Apc in the mouse intestine was found to be sufficient to drive expression of one of its enzymes, adenosylhomocysteinase (AHCY), which was also found to be transcriptionally upregulated in human CRC. Targeting of AHCY function impaired growth of APC-deficient organoids in vitro, and prevented the characteristic hyperproliferative/crypt progenitor phenotype driven by acute deletion of Apc in vivo, even in the context of mutant Kras. Finally, pharmacological inhibition of AHCY reduced intestinal tumour burden in ApcMin/+ mice indicating its potential as a metabolic drug target in CRC.

Protein expression of S100A2 reveals it association with patient prognosis and immune infiltration profile in colorectal cancer

PURPOSE

Colorectal cancer (CRC) is the third most diagnosed cancer worldwide. Despite a well-established knowledge of tumour development, biomarkers to predict patient outcomes are still required. S100 calcium-binding protein A2 (S100A2) has been purposed as a potential marker in many types of cancer, however, the prognostic value of S100A2 in CRC is rarely reported.

MATERIAL AND METHODS

In this study, immunohistochemistry (IHC) was performed to identify the prognostic role of S100A2 protein expression in the tumour core of the tissue microarrays (TMAs) in colorectal cancer patients (n=787). Bulk RNA transcriptomic data was used to identify significant genes compared between low and high cytoplasmic S100A2 groups. Multiplex immunofluorescence (mIF) was performed to further study and confirm the immune infiltration in tumours with low and high cytoplasmic S100A2.

RESULTS

Low cytoplasmic protein expression of S100A2 in the tumour core was associated with poor survival (HR 0.539, 95%CI 0.394-0.737, P<0.001) and other adverse tumour phenotypes. RNA transcriptomic analysis showed a gene significantly associated with the low cytoplasmic S100A2 group (AKT3, TAGLN, MYLK, FGD6 and ETFDH), which correlated with tumour development and progression. GSEA analysis identifies the enriched anti-tumour and immune activity group of genes in high cytoplasmic S100A2. Additionally, mIF staining showed that high CD3+FOXP3+ and CD163+ inversely associated with low cytoplasmic S100A2 (P<0.001, P=0.009 respectively).

CONCLUSION

Our finding demonstrates a prognostic value of S100A2 together with the correlation with immune infiltration in CRC.

High expression of STAT3 within the tumour-associated stroma predicts poor outcome in breast cancer patients

INTRODUCTION

Triple-negative breast cancer (TNBC) patients have the poorest clinical outcomes compared to other molecular subtypes of breast cancer. IL6/JAK/STAT3 signalling is upregulated in breast cancer; however, there is limited evidence for its role in TNBC. This study aimed to assess the expression of IL6/JAK/STAT3 in TNBC as a prognostic biomarker.

METHODS

Tissue microarrays consisting of breast cancer specimens from a retrospective cohort (n = 850) were stained for IL6R, JAK1, JAK2 and STAT3 via immunohistochemistry. Staining intensity was assessed by weighted histoscore and analysed for association with survival/clinical characteristics. In a subset of patients (n = 14) bulk transcriptional profiling was performed using TempO-Seq. Nanostring GeoMx® digital spatial profiling was utilised to establish the differential spatial gene expression in high STAT3 tumours.

RESULTS

In TNBC patients, high expression of stromal STAT3 was associated with reduced cancer-specific survival (HR = 2.202, 95% CI: 1.148-4.224, log rank p = 0.018). TNBC patients with high stromal STAT3 had reduced CD4⁺ T-cell infiltrates within the tumour (p = 0.001) and higher tumour budding (p = 0.003). Gene set enrichment analysis (GSEA) of bulk RNA sequencing showed high stromal STAT3 tumours were characterised by enrichment of IFNγ, upregulation of KRAS signalling and inflammatory signalling Hallmark pathways. GeoMx™ spatial profiling showed high stromal STAT3 samples. Pan cytokeratin (panCK)-negative regions were enriched for CD27 (p < 0.001), CD3 (p < 0.05) and CD8 (p < 0.001). In panCK-positive regions, high stromal STAT3 regions had higher expression of VEGFA (p < 0.05).

CONCLUSION

High expression of IL6/JAK/STAT3 proteins was associated with poor prognosis and characterised by distinct underlying biology in TNBC.

Risk stratification for the detection of metachronous polyps after bowel screening polypectomy: clinical outcomes from the Integrated Technologies for Improved Polyp Surveillance (INCISE) study cohort

BACKGROUND

After colorectal polypectomy, 20-50 per cent of patients develop metachronous polyps and some have increased colorectal cancer risk. British Society of Gastroenterology (BSG) 2020 guidelines recommend surveillance colonoscopy for high-risk patients based on index pathology. The aim of this study was to evaluate metachronous lesion outcome using BSG 2020 criteria.

METHODS

A retrospective, multicentred study was conducted including patients who had polypectomy during screening colonoscopy (2009-2016) followed by surveillance. Demographics, index pathology, and BSG 2020 risk criteria were compared with regard to metachronous lesion pathology (non-advanced versus advanced lesions) and timing of detection (early versus late). Advanced lesions were defined as adenomas/serrated polyps greater than or equal to 10 mm, high-grade dysplasia, serrated polyps with dysplasia, or colorectal cancer, and late lesions those detected greater than 2 years after the index procedure.

RESULTS

Of 3090 eligible patients, 2643 were included. Among these, retrospective BSG 2020 application would have excluded 51.5 per cent from surveillance. After a median of 36 months, the advanced polyp/colorectal cancer rate in BSG 2020 high-risk patients was 16.3 versus 13.0 per cent in low-risk patients. Older age (P = 0.008) correlated with advanced metachronous lesions. Male sex, greater than five polyps, and BSG 2020 high-risk criteria correlated with non-advanced and advanced lesions (P < 0.001). Older age (P < 0.001), villous features (P = 0.006), advanced index polyp (P = 0.020), and greater than five polyps (P < 0.001) correlated with early metachronous lesions. Male sex and BSG 2020 high-risk criteria correlated with early and late lesions (P < 0.001). On multivariable regression, increased polyp number (odds ratio (OR) 1.15 (95 per cent c.i. 1.07 to 1.25); P < 0.001) and villous features (OR 1.49 (95 per cent c.i. 1.05 to 2.10); P = 0.025) independently correlated with early advanced lesions. The rate of non-advanced and advanced metachronous polyps was higher in BSG 2020 high- versus low-risk patients (44.4 versus 35.4 per cent for non-advanced and 15.7 versus 11.8 per cent for advanced; P < 0.001), but the colorectal cancer rate was similar (0.6 versus 1.2 per cent). However, when examining only lesions detected greater than 2 years after the index colonoscopy in high- versus low-risk patients, no significant differences were observed (P = 0.140).

CONCLUSION

BSG 2020 criteria correlated with metachronous polyps, but did not differentiate advanced and non-advanced lesions and were not predictive of late lesions.

The relationship between carbonic anhydrase IX (CAIX) and patient survival in breast cancer: systematic review and meta-analysis

PURPOSE

Hypoxia is a characteristic of many solid tumours and an adverse prognostic factor for cancer therapy. Hypoxia results in upregulation of carbonic anhydrase IX (CAIX) expression, a pH-regulating enzyme. Many human tissue studies have examined the prognostic value of CAIX expression in breast cancer but have yielded inconsistent results. Therefore, a systematic review and meta-analysis was undertaken to assess the prognostic value of CAIX expression for breast cancer patients.

METHODS

The electronic databases were systematically searched to identify relevant papers. The clinical outcomes included disease-free survival (DFS), recurrence-free survival (RFS) and overall survival (OS) in breast cancer patients. Review Manager version 5.4 was employed to analysis data from 23 eligible studies (containing 8390 patients).

RESULTS

High CAIX expression was associated with poorer RFS [HR = 1.42, 95% CI (1.32-1.51), p < 0.00001], DFS [HR = 1.64, 95% CI (1.34-2.00), p < 0.00001], and OS [HR = 1.48, 95% CI (1.22-1.80), p < 0.0001]. Heterogeneity was observed across the studies. There was an effect of the CAIX antibody employed, scoring methods, and tumour localisation on CAIX expression.

CONCLUSION

CAIX overexpression was significantly associated with poorer RFS, DFS, and OS in breast cancer patients. However, further work in high quantity tissue cohorts is required to define the optimal methodological approach.

Spatially Resolved Transcriptomics Deconvolutes Prognostic Histological Subgroups in Patients with Colorectal Cancer and Synchronous Liver Metastases

Strong immune responses in primary colorectal cancer correspond with better patient survival following surgery compared with tumors with predominantly stromal microenvironments. However, biomarkers to identify patients with colorectal cancer liver metastases (CRLM) with good prognosis following surgery for oligometastatic disease remain elusive. The aim of this study was to determine the practical application of a simple histological assessment of immune cell infiltration and stromal content in predicting outcome following synchronous resection of primary colorectal cancer and CRLM and to interrogate the underlying functional biology that drives disease progression. Samples from patients undergoing synchronous resection of primary colorectal cancer and CRLM were evaluated in detail through histological assessment, panel genomic and bulk transcriptomic assessment, IHC, and GeoMx spatial transcriptomics (ST) analysis. High immune infiltration of metastases was associated with improved cancer-specific survival. Bulk transcriptomic analysis was confounded by stromal content, but ST demonstrated that the invasive edge of the metastases of long-term survivors was characterized by adaptive immune cell populations enriched for type II IFN signaling and MHC-class II antigen presentation. In contrast, patients with poor prognosis demonstrated increased abundance of regulatory T cells and neutrophils with enrichment of Notch and TGFβ signaling pathways at the metastatic tumor center. In summary, histological assessment can stratify outcomes in patients undergoing synchronous resection of CRLM, suggesting that it has potential as a prognostic biomarker. Furthermore, ST analysis has revealed significant intratumoral and interlesional heterogeneity and identified the underlying transcriptomic programs driving each phenotype.

SIGNIFICANCE

Spatial transcriptomics uncovers heterogeneity between patients, between matched lesions in the same patient, and within individual lesions and identifies drivers of metastatic progression in colorectal cancer with reactive and suppressed immune microenvironments.

Abstract 4691: Spatially resolved transcriptomics deconvolutes histological prognostic subgroups in patients with colorectal cancer and synchronous liver metastases

Patients demonstrating strong immune responses to primary colorectal cancer (CRC) have a survival benefit following surgery, while those with predominantly stromal microenvironments do poorly. Biomarkers to identify patients with colorectal cancer liver metastases (CRLM) who have good prognosis following surgery for oligometastatic disease remain elusive. The aim of this study was to determine the practical application of a simple histological assessment of immune cell infiltration and stromal content in predicting outcome following synchronous resection of primary CRC and CRLM, and to interrogate the underlying functional biology that drives disease progression. Patients undergoing synchronous resection of primary CRC and CRLM underwent detailed histological assessment, panel genomic and bulk transcriptomic assessment, immunohistochemistry (IHC) and GeoMx Spatial Transcriptomics (ST) analysis. Integration with genomic features, pathway enrichment analysis and immune deconvolution were performed. High-immune metastases were associated with improved cancer specific survival (HR, 0.36, P=0.01). Bulk transcriptomic analysis was confounded by stromal content but ST demonstrated that the invasive edge of the metastases of long-term survivors was characterized by adaptive immune cell populations enriched for Type II Interferon signaling (NES=-2.05 P.Adj&lt;0.005) and MHC-Class II Antigen Presentation (NES=-2.09 P.Adj&lt;0.005). In contrast, patients with poor prognosis demonstrated increased abundance of regulatory T-cells and neutrophils with enrichment of Notch (NES=2.2 P.Adj=0.022) and TGF-β (NES=2.2 P.Adj=0.02) signaling pathways at the metastatic tumor center. In summary, histological assessment can stratify outcome in patients undergoing synchronous resection of CRLM and ST analysis has revealed significant intra-tumoral and inter-lesional heterogeneity with underlying transcriptomic programs identified in driving each phenotype.

Citation Format: Colin S. Wood, Kathryn A. Pennel, Holly Leslie, Assya Legrini, Andrew J. Cameron, Paul Horgan, Joanne Edwards, Colin W. Steele, Nigel B. Jamieson. Spatially resolved transcriptomics deconvolutes histological prognostic subgroups in patients with colorectal cancer and synchronous liver metastases. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4691.

Abstract 3231: Temporal changes in intratumoral and systemic lymphocytes in response to short and long course radiotherapy regimens in locally advanced rectal cancer

Background. Two pre-operative radiotherapy (RT) regimens are in common use for patients (pts) with locally advanced rectal cancer (LARC): Conventionally fractionated, long course chemoradiation (LCCRT, 25x1.8Gy with concomitant chemotherapy) or hypofractionated short-course RT (5X5Gy) followed by systemic chemotherapy (SCRT-C). RT is thought to induce immune responses to cellular damage, but the understanding of their evolution and relation to fractionation is limited. We are conducting a serial biospecimen collection in such pts with baseline, 2, 6 and 12 week (wk) sampling. We report serial measurement of tumor and peripheral blood lymphocyte responses for each regimen.

Method. Multiplex immunofluorescence quantified tumor infiltrating lymphocytes (CD8, FOXP3). Routine diagnostic flow cytometry quantified circulating lymphocytes. A multiplex ELISA quantified cytokines in blood plasma. Bulk RNA-sequencing (QuantSeq) quantified gene expression within the tumor.

Result. We report results for 20pts who received RT for stage III/IV LARC (13 LCCRT, 7 SCRT-C). Biopsy results are available for 10pts, circulating lymphocytes for 20pts and peripheral blood cytokines for 16pts. In LCCRT patients (n=8), relative to baseline, tumor infiltrating cytotoxic (CD8+) T cells were uniformly decreased during (2wks, P&lt;0.05) and directly after treatment (6wks, P&lt;0.05) before returning to baseline at 12wks. T regulatory cells (FOXP3+) similarly significantly decreased at 2wks and 6wks but remained below baseline at 12wks (P&lt;0.05). Circulating lymphocytes also fell at wk2 and wk6 after commencing LCCRT and had begun recovering by wk12(n=13; P&lt;0.05). The concentrations of circulating interleukins secreted by (IL2, IL8) or which activate T-lymphocytes (IL2, IL15) were reduced in the circulation at wk2 (n= 9; P&lt;0.05) and wk6 (NS). In SCRT-C patients, we noted an increase in CD8 T cells at 2wks in 2/2 pts, also reflected in gene expression data, and an increase in FOXP3 T cells in 1/2 pts. Circulating lymphocytes were similarly decreased at wk2 in both the SCRT-C (n=7) and LCCRT (n=13) pts, but this reduction was less marked within the SCRT-C cohort at wk6 (P&lt;0.01) and wk12 (P&lt;0.05) relative to LCCRT patients. IL2, IL8 and IL15 did not change during or after SCRT-C (n=7; NS).

Conclusion. LCCRT caused a drop in T cells during treatment, whilst SCRT-C appears to induce intra-tumoral T cell responses from wk2 and abrogates systemic reactions to a lesser extent. These results require evaluation in a larger cohort but have implications for understanding how RT induces microenvironmental changes and impacts pelvic bone marrow. We show in vivo that SCRT may be more immunostimulatory in LARC, with implications for trials combining RT with immunotherapy.

Citation Format: Lily V. Hillson, Ross K. McMahon, Kathryn A. Pennel, Jean A. Quinn, Leia Jones, Raheleh Amirkhah, Aula Ammar, Phimmada Hatthakarnkul, Annabelle Ferguson, Simon W. Milling, Alec McDonald, Philip D. Dunne, Joanne Edwards, Sean M. O'Cathail, Campbell S. Roxburgh. Temporal changes in intratumoral and systemic lymphocytes in response to short and long course radiotherapy regimens in locally advanced rectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3231.

Carbonic anhydrase IX-related tumoral hypoxia predicts worse prognosis in breast cancer: A systematic review and meta-analysis

Background

Tumoral hypoxia is associated with aggressiveness in many cancers including breast cancer. However, measuring hypoxia is complicated. Carbonic anhydrase IX (CAIX) is a reliable endogenous marker of hypoxia under the control of the master regulator hypoxia-inducible factor-1α (HIF-1α). The expression of CAIX is associated with poor prognosis in many solid malignancies; however, its role in breast cancer remains controversial.

Methods

The present study performed a meta-analysis to evaluate the correlation between CAIX expression and disease-free survival (DFS) and overall survival (OS) in breast cancer.

Results

A total of 2,120 publications from EMBASE, PubMed, Cochrane, and Scopus were screened. Of these 2,120 publications, 272 full texts were reviewed, and 27 articles were included in the meta-analysis. High CAIX was significantly associated with poor DFS (HR = 1.70, 95% CI = 1.39–2.07, p &lt; 0.00001) and OS (HR = 2.02, 95% CI 1.40–2.91, p = 0.0002) in patients with breast cancer. When stratified by subtype, the high CAIX group was clearly associated with shorter DFS (HR = 2.09, 95% CI =1.11–3.92, p = 0.02) and OS (HR = 2.50, 95% CI =1.53–4.07, p = 0.0002) in TNBC and shorter DFS in ER+ breast cancer (HR = 1.81 95% CI =1.38–2.36, p &lt; 0.0001).

Conclusion

High CAIX expression is a negative prognostic marker of breast cancer regardless of the subtypes.

Association of wnt signalling with metachronous colonic polyp risk

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Background: Following colorectal polypectomy, 20-50% of patients develop metachronous polyps, and a proportion have increased colorectal cancer (CRC) risk. However, there are currently no molecular biomarkers for predicting metachronous polyp risk. Constitutive activation of the Wnt signalling cascade is a hallmark of polyp development and carcinogenesis, therefore biomarkers from this pathway were investigated for association with detection of metachronous polyps. Methods: A retrospective study was performed on a tissue microarray (TMA) of left sided colonic polyps from 279 patients undergoing screening polypectomy (May’09-Dec’16) followed by surveillance colonoscopy (up to 6 years). Mutational analysis was performed using the GPOL cancer plus panel, protein expression by Immunohistochemistry and RNA-sequencing by TempO-Seq (BioClavis). Log rank statistics determined associations with time to detection of metachronous polyp. Index polyp number, histology and size were compared to metachronous lesion outcome using χ2/ANOVA and multivariate polynomial regression identified independent predictors of advanced future lesions. Results: APC (91%), KRAS (30%) and SOX9 (23%) were the most frequently mutated genes and APC and SOX9 are both implicated in Wnt signalling. Mutations in APC and co-mutations in SOX9 with ARID1 were associated with a shorter time to detection of metachronous polyps. Neither variant classification nor location of mutations were associated with metachronous polyp detection. Luminal epithelial cells with high expression of E-Cadherin or SOX9 were significantly associated with earlier detection of metachronous polyps or CRC (HR 2.3, 95%CI 1.6-3.3: p<0.001 and: HR 2.0, 95%CI 1.3-3.0; p=0.001 respectively). By χ2/ANOVA analysis, E-Cadherin and SOX9 expression was associated with detection of metachronous polyp (p>0.001, p=0.037 respectively). On multivariate regression, number of polyps (HR 1.2, 95%CI 1.1-1.3; p<0.001), and E-Cadherin expression (HR 2.1, 95%CI 1.5-3; p<0.001), independently predicted metachronous lesions. Gene set enrichment analysis (GSEA) was used to explore differential biology between high and low E-Cadherin or SOX9 expression. For E-Cadherin, all seven immune-annotated MSigDB hallmarks had negative enrichment, however Wnt--catenin signaling was positively enriched (NES=1.50, p-adj<0.1). The top signature enriched for SOX9 was ‘NFB signaling via TNF (NES=1.70, p-adj<0.001). The LGR5 stemness signature was enriched in both high E-Cadherin (NES=1.97 p-adj<0.0001) and high SOX9 (NES=1.48, p-adj<0.0001) groups. Conclusions: Wnt signalling-associated protein expression within index polyp tissue is valuable for predicting metachronous polyp risk. In addition, expression of E-Cadherin and SOX9 in colonic polyps are linked to immune and stemness signatures, suggesting immune and stemness biology may be an underlying driver of metachronous polyp development.

Durvalumab (MEDI 4736) with extended neoadjuvant regimens in rectal cancer: A randomised phase II trial (PRIME-RT)

TPS282

Background: Advances in multi-modality treatment of locally advanced rectal cancer (LARC) have resulted in low local recurrence rates, but many patients still die from distant disease. There is increasing recognition that with neoadjuvant treatment some patients achieve a complete response and may avoid surgical resection. PRIME-RT tests the inclusion of neoadjuvant immunotherapy with the aim of enhancing complete response rates, improving stoma-free survival and reducing distant relapse. Methods: PRIME-RT is a multi-centre, open label, phase II, randomised trial for patients with newly diagnosed LARC. Eligible patients are randomised to Arm A: short course radiotherapy (25 Gray in 5 fractions) with concomitant durvalumab, followed by durvalumab and FOLFOX chemotherapy, or Arm B: long course chemoradiotherapy (50 Gray to primary tumour, 45 Gray to elective nodes, in 25 fractions with capecitabine) with concomitant durvalumab followed by FOLFOX and durvalumab. The primary endpoint is complete response rate in each arm. Bio-specimens including serial tumour biopsies and peripheral blood samples are collected prior to, during, and following treatment to explore the molecular and immunological factors underpinning treatment response. The main trial will recruit up to 42 patients and commence after a safety run-in which is recruiting patients with metastatic disease. After opening in January 2021, the four patients completed the safety run in and the main trial commenced in March 2022. The trial is currently open across 5 UK sites. Up to date recruitment details will be provided at the time of presentation but at the time of writing this is ahead of target. Early recruitment to PRIME-RT has shown that adding immunotherapy in the neoadjuvant setting for LARC is feasible. Furthermore, on treatment biospecimen collection is also feasible across multiple sites. The expectation is that the trial will provide efficacy and safety information which allows the optimal treatment approach to be tested within a larger phase clinical trial. Core funding (Glasgow CRUK CTU) and trial-specific funding (Astrazeneca). Clinical trial: NCT04621370; ISRCTN18138369. Clinical trial information: ISRCTN18138369 .

The association between KRAS mutational status, clinicopathological factors including the preoperative systemic inflammatory response and outcomes in TNM stage I-III colon cancer

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Background: TNM Stage is the most significant prognostic indicator in colon cancer however other tumour and host factors (eg the systemic inflammatory response (SIR)) are associated with long-term outcomes. The relationship between the tumour and the host SIR remains poorly understood. KRAS mutations are associated with adverse outcomes in metastatic disease and have been reported to have an inflammatory phenotype however this has not been widely studied in non-metastatic disease. The present study investigates the association between KRAS mutations, clinicopathological factors including the SIR and outcomes in TNM I-III colon cancer. Methods: Two cohorts of patients (single centre–2000-2008 and regional-2011-2014) undergoing curative surgery for TNM I-III colon cancer in the West of Scotland were shown to be well-matched and combined. Mutational status was analysed retrospectively. The SIR was stratified using Systemic Inflammatory Grade (SIG). 3-year overall and cancer specific survival (OS and CSS) were measured from date of surgery until date of death. Results: 267 patients were identified, 45% with KRAS mutations. KRAS mutations were associated with: right sided (p=0.013), well differentiated (p=0.011), BRAF-wt (p<0.001), PIK3CA-wt (p=0.027) and P53-wt (p=0.002) tumours. A trend was seen between KRAS mutations and female sex (p=0.074) and increased SIG (p=0.072). No association was seen with age, deprivation, smoking, ASA Grade, TNM Stage or EMVI. KRAS mutant status was associated with adverse 3-year CSS (74% versus 82%, p=0.006) and OS (69% versus 78%, p=0.070). For CSS, TNM Stage (HR 2.92, p<0.001), KRAS mutant status (HR 1.64, p=0.050) and Systemic Inflammatory Grade (HR 1.34, p=0.004) were independently prognostic. For OS: age (HR 1.39, p=0.022), TNM Stage (HR 1.50, p=0.016) and SIG (HR 1.25, p=0.005) were independently prognostic. A trend was seen between KRAS mutant status and adverse OS (HR 1.47, p=0.079). Conclusions: The present results show an association between KRAS mutational status and SIG. Furthermore, both of these factors were associated with adverse oncological outcomes. Further investigation into the association between KRAS-mutant status and the local/systemic inflammatory response in TNM I-III colon cancer is warranted. While comprehensive genomic profiling is likely to become increasingly common place, staging the host (SIR) should also be routinely undertaken.

Immunohistochemical assessment of COX2, P53, and beta-catenin expression to predict metachronous lesion development following polypectomy

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Background: Following colorectal polypectomy, 20-50% develop metachronous polyps, and some have increased colorectal cancer (CRC) risk. Surveillance colonoscopy is recommended to high-risk patients, based on index polyp number, histology and size. We aimed to assess if COX2, p53 and beta-catenin expression could predict metachronous polyp/ CRC risk. Methods: Tissue microarrays (TMA’s) were constructed for 339 patients from the INCISE study, a retrospective analysis of all patients undergoing screening polypectomy (Apr’09-Dec’16) followed by surveillance (6months-6years) in Glasgow, UK. Epithelial COX2, p53 and beta-catenin expression were assessed for each patient’s most advanced index polyp using immunohistochemistry, quantified by QuPath software. Kaplan-Meier analysis, log-rank tests and univariate/ multivariate cox regression assessed the association between marker expression and time to metachronous polyp/ CRC detection. Results: Low nuclear p53 expression was associated with shorter time to metachronous polyp/ CRC detection (p=0.024). Low nuclear (p=0.012) and membranous (p=0.046) beta-catenin expression was associated with shorter time to metachronous polyp/ CRC detection. There was no association between cytoplasmic COX2 expression and time to metachronous polyp/ CRC detection overall (p=0.309), but high cytoplasmic COX2 expression was associated with shorter time to detection of advanced metachronous lesions (advanced colorectal polyps/ CRC) (p=0.011). A combined score using the two most powerful biomarkers (nuclear p53 and nuclear beta-catenin – both high/ one low/ both low) was also associated with shorter time to metachronous polyp/ CRC detection (p=0.011). Univariate and multivariate cox regression are shown. Conclusions: Index polyp number and combined nuclear p53/beta-catenin expression independently predicted time to metachronous polyp/ CRC detection. [Table: see text]

Effect of spatial transcriptomic-derived intrinsic epithelial signatures on immune cell recruitment and behaviour in the microenvironment of colorectal cancer

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Background: Colorectal Cancer (CRC) remains a significant healthcare problem. Interest in the role of the Tumour Microenvironment (TME) in progression and metastasis is established, yet much remains to be learned about the mechanism of immune cell recruitment to the TME of primary and metastatic tumours. The Klintrup Makinen (KM) score measures the density of immune infiltrate to the invasive edge of tumours and is associated with good prognosis in primary CRC. Neutrophil infiltration to metastases is a poor prognostic feature suggesting phenotypic differences in the TME at primary and metastatic sites. We set out to examine epithelial determination of the TME in primary CRC. Methods: 180 patient’s primary CRC from a curated TMA underwent deep phenotyping using a multiplex-immunofluorescent panel (DAPI, Panck, CD3 (T cells), FOXP3 (T regulatory cells), CD68 (Macrophages), CD163 (Tumour associated macrophage), CD66b (Neutrophils), KI67). The Nanostring GeoMx Spatial Transcriptomic platform was used to obtain segmented (Tumour: Panck+; TME: Panck-) whole transcriptomic (18000 genes) readout from 54 matched cores from the same TMA. Results: No significant association was demonstrated between immune cell density of any cell types and clinicopathological variables including tumour side, MMR status, N-stage or survival. High KM grade was associated with high CD3 (P = 0.01) and FOXP3 (P = 0.002). Density of all immune cell types were highly corelated. Spatial transcriptomic analysis of the segmented epithelium of patients with high KM grade demonstrated over-expression of known neutrophil chemo-attractant CXCL5 (log2FC 3.76 Adj.P < 0.005). The TME compartments of cores with high CD68 and low CD163 counts were associated with adaptive immune co-ordination with high expression of CXCL13 (log2FC -2.97, Adj.P < 0.005) and CD74 (log2FC -1.42 Adj.P 0.007). IGF2 (log2FC 6.08 Adj.P < 0.005) and LCN15 (log2FC 4.96 Adj.P < 0.005) were globally over-expressed in both TME and epithelium of cores with generalised low immune infiltration. The epithelial compartment neutrophil dense cores also over-expressed IGF2 (log2FC -3.53 Adj.P 0.02). Conclusions: TMAs provide a unique opportunity for broad transcriptomic phenotyping of large numbers of patients simultaneously. The Nanostring GeoMx platform is a flexible tool which can be used in novel ways with other proteomic technologies to drive deeper analysis of the TME. CXCL5 expression in the epithelial compartment drives global immune infiltration to the TME and may be manipulated in different contexts therapeutically through CXCR2 signalling in future.

The Glasgow Microenvironment Score and risk and site of recurrence in TNM I-III colorectal cancer

BACKGROUND

Glasgow Microenvironment Score (GMS) stratifies long-term survival into three groups based on tumour phenotype: peritumoural inflammation (Klintrup-Mäkinen (KM)) and tumour stroma percentage (TSP). However, it is not known if the location of disease recurrence is influenced by the GMS category.

METHODS

Seven hundred and eighty-three TNM I-III colorectal cancers (CRC) were included. GMS (GMS0-high KM; GMS1-low KM, low TSP; GMS2-low KM, high TSP) and cancer-specific survival (CSS), overall survival (OS) and disease recurrence were assessed using Cox regression analysis.

RESULTS

Of the 783 patients, 221 developed CRC recurrence; 65 developed local recurrence + systemic disease. GMS was independent for CSS (HR 1.50, 95% CI 1.17-1.92, p < 0.001) and OS (HR 1.23, 1.05-1.44, p = 0.01). Higher GMS category was associated with T-stage, N-stage, emergency presentation and venous invasion. GMS was independent for local+systemic recurrence (HR 11.53, 95% CI 1.45-91.85, p = 0.04) and distant-only recurrence (HR 3.01, 95% CI 1.59-5.71, p = 0.002). GMS 2 disease did not appear to have statistically better outcomes with adjuvant chemotherapy in high-risk disease.

CONCLUSION

Although confounded by a higher rate of T4 and node-positive disease, GMS 1 and 2 are associated with an increased risk of local and distant recurrence. GMS is an independent poor prognostic indicator for recurrent colorectal cancer. Higher GMS patients may benefit from enhanced postoperative surveillance.

Association of punctate TAK1 expression with mortality in patients with microsatellite-stable colorectal cancer

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Background: Microsatellite stable (MSS) colorectal cancer continues to have limited options for personalised therapeutic targets. The NFKB pathway is known to play an important role in inflammation-related carcinogenesis but has yet to be translated into therapies for the clinical patient. The aim of this study was to investigate the expression of cytoplasmic and punctate TAK1 (transforming growth factor β-activated protein kinase 1) in colorectal cancer and its relationship to immune checkpoint expression and prognosis. Methods: Patients undergoing primary colorectal cancer resection between 1997 and 2007 at Glasgow Royal Infirmary (UK) were studied for clinicopathological data and immunohistochemistry (IHC) performed on archival FFPE tissue from resected specimens. Antibodies for TAK1, PD-1, PD-L1, IKK alpha and other proteins were used for IHC, with digital analysis (QuPath) for quantification of cytoplasmic staining and punctate score for juxta-nuclear TAK1 assessment. Kaplan-Meier curves were created with log-rank test to determine survival. Cox-proportional hazards regression were used to determine multivariate hazard ratios (HR) and 95% confidence intervals (CI). Results: A total of 898 patients who underwent colorectal resection were identified. Higher TAK1 punctate expression was observed in left colon and rectal cancer, compared with right sided disease (p = 0.045). MMR proficient tumours had higher frequencies of high TAK1 punctate expression (p < 0.001). Both cytoplasmic and punctate TAK1 expression correlated with IKK expression (p < 0.050). High cytoplasmic TAK1 expression was associated with increased PD-1 and PD-L1 expression (p < 0.001). Punctate TAK1 expression was associated with worse survival (p = 0.037). These differences were accentuated in patients with MSS status (p = 0.016). On multivariate analysis, high punctate TAK1 expression remained a predictor of worse cancer-specific survival (HR 1.843, CI 1.129-2.956, p = 0.011). Conclusions: TAK1 expression was associated with MSI status, and higher TAK1 expression correlates with upregulated PD-1 and PD-L1 expression. High punctate TAK1 expression predicted cancer-specific survival. In subgroup analysis of MSS patients, high punctate TAK1 expression was associated with poor survival. Further interrogation into this pathway may identify inflammation-related therapeutic targets in MSS patients with colorectal cancer.

Dual inhibition of HSF1 and DYRK2 impedes cancer progression

Preserving proteostasis is a major survival mechanism for cancer. Dual specificity tyrosine phosphorylation-regulated kinase 2 (DYRK2) is a key oncogenic kinase that directly activates the transcription factor heat-shock factor 1 (HSF1) and the 26S proteasome. Targeting DYRK2 has proven to be a tractable strategy to target cancers sensitive to proteotoxic stress; however, the development of HSF1 inhibitors remains in its infancy. Importantly, multiple other kinases have been shown to redundantly activate HSF1 that promoted ideas to directly target HSF1. The eventual development of direct HSF1 inhibitor KRIBB11 suggests that the transcription factor is indeed a druggable target. The current study establishes that concurrent targeting of HSF1 and DYRK2 can indeed impede cancer by inducing apoptosis faster than individual targetting. Furthermore, targeting the DYRK2-HSF1 axis induces death in proteasome inhibitor-resistant cells and reduces triple-negative breast cancer (TNBC) burden in ectopic and orthotopic xenograft models. Together the data indicate that cotargeting of kinase DYRK2 and its substrate HSF1 could prove to be a beneficial strategy in perturbing neoplastic malignancies.

Prognostic role of preoperative circulating systemic inflammatory response markers in primary breast cancer: meta-analysis

BACKGROUND

Circulating markers of the systemic inflammatory response are prognostic in several cancers, but their role in operable breast cancer is unclear. A systematic review and meta-analysis of the literature was carried out.

METHODS

A search of electronic databases up to August 2020 identified studies that examined the prognostic value of preoperative circulating markers of the systemic inflammatory response in primary operable breast cancer. A meta-analysis was carried out for each marker with more than three studies, reporting a HR and 95 per cent confidence interval for disease-free survival (DFS), breast cancer-specific survival (BCSS) or overall survival (OS).

RESULTS

In total, 57 studies were reviewed and 42 were suitable for meta-analysis. Higher neutrophil-to-lymphocyte ratio (NLR) was associated with worse overall survival (OS) (pooled HR 1.75, 95 per cent c.i. 1.52 to 2.00; P < 0.001), disease-free survival (DFS) (HR 1.67, 1.50 to 1.87; P < 0.001), and breast cancer-specific survival (BCSS) (HR 1.89, 1.35 to 2.63; P < 0.001). This effect was also seen with an arithmetically-derived NLR (dNLR). Higher platelet-to-lymphocyte ratio (PLR) was associated with worse OS (HR 1.29, 1.10 to 1.50; P = 0.001) and DFS (HR 1.58, 1.33 to 1.88; P < 0.001). Higher lymphocyte-to-monocyte ratio (LMR) was associated with improved DFS (HR 0.65, 0.51 to 0.82; P < 0.001), and higher C-reactive protein (CRP) level was associated with worse BCSS (HR 1.22, 1.07 to 1.39; P = 0.002) and OS (HR 1.24, 1.14 to 1.35; P = 0.002).

CONCLUSION

Current evidence suggests a role for preoperative NLR, dNLR, LMR, PLR, and CRP as prognostic markers in primary operable breast cancer. Further work should define their role in clinical practice, particularly reproducible thresholds and molecular subtypes for which these may be of most value.

Incisional hernia following colorectal cancer surgery according to suture technique: Hughes Abdominal Repair Randomized Trial (HART)

BACKGROUND

Incisional hernias cause morbidity and may require further surgery. HART (Hughes Abdominal Repair Trial) assessed the effect of an alternative suture method on the incidence of incisional hernia following colorectal cancer surgery.

METHODS

A pragmatic multicentre single-blind RCT allocated patients undergoing midline incision for colorectal cancer to either Hughes closure (double far-near-near-far sutures of 1 nylon suture at 2-cm intervals along the fascia combined with conventional mass closure) or the surgeon's standard closure. The primary outcome was the incidence of incisional hernia at 1 year assessed by clinical examination. An intention-to-treat analysis was performed.

RESULTS

Between August 2014 and February 2018, 802 patients were randomized to either Hughes closure (401) or the standard mass closure group (401). At 1 year after surgery, 672 patients (83.7 per cent) were included in the primary outcome analysis; 50 of 339 patients (14.8 per cent) in the Hughes group and 57 of 333 (17.1 per cent) in the standard closure group had incisional hernia (OR 0.84, 95 per cent c.i. 0.55 to 1.27; P = 0.402). At 2 years, 78 patients (28.7 per cent) in the Hughes repair group and 84 (31.8 per cent) in the standard closure group had incisional hernia (OR 0.86, 0.59 to 1.25; P = 0.429). Adverse events were similar in the two groups, apart from the rate of surgical-site infection, which was higher in the Hughes group (13.2 versus 7.7 per cent; OR 1.82, 1.14 to 2.91; P = 0.011).

CONCLUSION

The incidence of incisional hernia after colorectal cancer surgery is high. There was no statistical difference in incidence between Hughes closure and mass closure at 1 or 2 years.

REGISTRATION NUMBER

ISRCTN25616490 (http://www.controlled-trials.com).

CXCL8 expression is associated with advanced stage, right sidedness, and distinct histological features of colorectal cancer

CXCL8 is an inflammatory chemokine elevated in the colorectal cancer (CRC) tumour microenvironment. CXCR2, the major receptor for CXCL8, is predominantly expressed by neutrophils. In the cancer setting, CXCL8 plays important roles in neutrophil chemotaxis, facilitating angiogenesis, invasion, and metastasis. This study aimed to assess the spatial distribution of CXCL8 mRNA expression in CRC specimens, explore associations with clinical characteristics, and investigate the underlying biology of aberrant CXCL8 levels. CXCR2 expression was also assessed in a second cohort of unique CRC primary tumours and synchronously resected matched liver metastases. A previously constructed tissue microarray consisting of a cohort of stage I-IV CRC patients undergoing surgical resection with curative intent (n = 438) was probed for CXCL8 via RNAscope®. Analysis was performed using HALO® digital pathology software to quantify expression in the tumour and stromal compartments. Scores were assessed for association with clinical characteristics. Mutational analyses were performed on a subset of these patients to determine genomic differences in patients with high CXCL8 expression. A second cohort of stage IV CRC patients with primary and matched metastatic liver tumours was stained via immunohistochemistry for CXCR2, and scores were assessed for clinical significance. CXCL8 expression within the stromal compartment was associated with reduced cancer-specific survival in the first cohort (p = 0.035), and this relationship was potentiated in right-sided colon cancer cases (p = 0.009). High CXCL8 within the stroma was associated with driving a more stromal-rich phenotype and the presence of metastases. When stromal CXCL8 scores were combined with tumour-infiltrating macrophage counts or systemic neutrophil counts, patients classified as high for both markers had significantly poorer prognosis. CXCR2+ immune cell infiltration was associated with increased stromal invasion in liver metastases (p = 0.037). These data indicate a role for CXCL8 in driving unfavourable tumour histological features and promoting metastases. This study suggests that inhibiting CXCL8/CXCR2 should be investigated in patients with right-sided colonic disease and stroma-rich tumours.

Cellular localization of nucleolin determines the prognosis in cancers: a meta-analysis

Nucleolin (NCL) is a multifunctional protein expressed in the nucleus, cytoplasm, and cell membrane. Overexpression of NCL has a controversial role as a poor prognostic marker in cancers. In this study, a meta-analysis was performed to evaluate the prognostic value of NCL in different subcellular localizations (cytoplasmic (CyNCL) and nuclear (NuNCL)) across a range of cancers. PubMed was searched for relevant publications. Data were extracted and analyzed from 12 studies involving 1221 patients with eight cancer types. The results revealed high total NCL was significantly associated with poor overall survival (OS) (HR = 2.85 (1.94, 4.91), p < 0.00001, I² = 59%) and short disease-free survival (DFS) (HR = 3.57 (2.76, 4.62), p < 0.00001, I² = 2%). High CyNCL was significantly associated with poor OS (HR = 4.32 (3.01, 6.19), p < 0.00001, I² = 0%) and short DFS (HR = 3.00 (2.17, 4.15), p < 0.00001, I² = 0%). In contrast, high NuNCL correlated with increased patient OS (HR = 0.42 (0.20, 0.86), p = 0.02, I² = 66%), with no significant correlation to DFS observed (HR = 0.46 (0.19, 1.14), p = 0.09, I² = 57%). This study supports the role of subcellular NCL as a poor prognostic cancer biomarker.

The Relationship Between the Tumor Cell Expression of Hypoxic Markers and Survival in Patients With ER-positive Invasive Ductal Breast Cancer

The prognostic significance of hypoxia markers, hypoxia-inducible factor-1α (HIF-1α), hypoxia-inducible factor-2α (HIF-2α), and carbonic anhydrase IX (CAIX), was investigated in estrogen receptor (ER)-positive breast cancer patients. Immunohistochemistry determined the expression of makers in two independent ductal ER-positive cohorts (Training set, n=373 and Validation set, n=285) and was related to clinicopathological parameters and disease-free survival (DFS). In the training cohort, nuclear HIF-1α (1) was independently associated with poorer DFS in luminal A tumors [hazard ratio (HR) = 0.53 95% confidence interval (CI): 0.30–0.94, p=0.030]. In the validation cohort, both HIF-1α (1) and CAIX were independently associated with decreased DFS in the entire cohort (HR = 1.85 95% CI: 1.10–3.11, p=0.019; HR = 1.74 95% CI: 1.08–2.82, p=0.023), in luminal A disease (HR = 1.98 95% CI: 1.02–3.83, p=0.042), and in luminal B disease (HR = 2.75 95% CI: 1.66–4.55, p<0.001), respectively. Taken together, elevated cytoplasmic HIF-1α (1) expression was an independent prognostic factor in luminal A disease, whereas CAIX was an independent prognostic factor in luminal B disease. Further work in large tissue cohorts is required.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

Abstract 2031: High plex proteomic prognostic marker discovery for patients with pancreatic adenocarcinoma using digital spatial profiling

Pancreatic Ductal Adenocarcinoma (PDAC) long-term outcomes following surgical resection remain poor, with only 20% of patients surviving 5 years post pancreatectomy. With its immune-privileged nature, starting from the early pre-neoplastic state, it appears to easily evade the antitumor immune response. Although there is rationale for targeting PDAC immune pathways, little benefit has been observed to date. The aim of the study was to interrogate the immune landscape of PDAC utilising the  Nanostring GeoMx Digital Spatial Profiler (DSP), enabling high-plex proteomic characterisation whilst maintaining tumor microenvironment (TME) topographical features.

We assessed tumor samples from 28 treatment-naive PDAC cases represented in a multiregional FFPE tissue microarray (TMA) for which extensive IHC, molecular, genomic characterisation and clinicopathological follow-up data is available. Multiplex immunofluorescent staining for nuclei, panCK, aSMA and CD3 was used to guide region selection using the GeoMx DSP system in multiple TMA cores. 60 immune markers were quantified simultaneously in different tissue compartments defined by immunofluorescence co-localization including tumor (panCK+), immune stromal (PanCK-) regions.

The spatially informed assessment by DSP was validated by both regression and variable prognostication compared with IHC for stromal CD3, CD8 and CD68 in near serial TMA PDAC sections. Unsupervised analysis of proteome data (DSP) in the panCK-negative regions identified an immune poor group associated with shorter OS (13.0 versus 31.1mths, P=0.005). When transcriptomic subtype was considered, the checkpoint inhibitor B7-H3 was significantly upregulated in the squamous subtype tumours versus the classical group (Log2: 1.63, P = 0.001). Patients with high B7-H3 expression, using a median expression cut-off, were associated with shorter OS on multivariate analysis (HR: 4.16, P=0.01) a finding that was validated in an external cohort at the bulk transcriptome level.

This pilot scale discovery study shows the potential of the Nanostring DSP technology to identify spatially-informed biomarkers with prognostic relevance in biopsy sized samples from treatment-naive PDAC. A number of relevant candidate immune predictors were identified in a spatial context, which are currently undergoing validation in a larger independent cohort and within the neoadjuvant setting. Future studies will apply this technology to pre and post treatment biopsy samples. 

Citation Format: Assya Legrini, Holly Leslie, Stephan Dreyer, Joanne Edwards, Andrew Biankin, David Chang, Nigel Jamieson. High plex proteomic prognostic marker discovery for patients with pancreatic adenocarcinoma using digital spatial profiling [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2031.

The relationship between the Glasgow Microenvironment Score and Markers of Epithelial-to-Mesenchymal Transition in TNM II-III Colorectal Cancer

BACKGROUND

Recently published work on the Glasgow Microenvironment Score (GMS) demonstrated its relevance as a biomarker in TNM II-III colorectal cancer (CRC). Epithelial-to-Mesenchymal Transition (EMT) markers in colorectal cancer have also shown promise as prognostic biomarkers. This study aimed to assess the relationship between GMS and markers of EMT in stage II-III CRC.

PATIENTS AND METHODS

A previously constructed tissue microarray of CRC tumours resected between 2000 and 2007 from the Western Infirmary, Stobhill and Gartnavel General hospitals in Glasgow was used. Immunohistochemistry was performed for five markers of EMT: E-cadherin, B-catenin, Fascin, Snail and Zeb1. Two-hundred and thirty-eight TNM II-III CRC with valid scores for all EMT markers and GMS were assessed. The prognostic significance of markers of EMT in this cohort and relationships between GMS and markers of EMT were determined.

RESULTS

High cytoplasmic and nuclear B-catenin and membrane Zeb-1 were significant for worse CSS (HR 1.67, 95% CI 1.01-2.76, p<0.05; HR 2.22, 95% CI 1.24-3.97, p<0.01; and HR 2.00, 95% CI 1.07-3.77, p=0.03, respectively). GMS 0 associated with low membrane Fascin (p=0.03), whereas membrane and cytoplasmic Fascin were observed to be highest in GMS 1, but lower in GMS 2. Nuclear B-catenin was lowest in GMS 0, but highest in GMS 2 (p=0.03), in keeping with its role in facilitating EMT.

CONCLUSIONS

Novel associations were demonstrated between GMS categories and markers of EMT, particularly B-catenin and Fascin, which require further investigation in independent cohorts.

THEM6-mediated reprogramming of lipid metabolism supports treatment resistance in prostate cancer

Despite the clinical benefit of androgen-deprivation therapy (ADT), the majority of patients with advanced prostate cancer (PCa) ultimately develop lethal castration-resistant prostate cancer (CRPC). In this study, we identified thioesterase superfamily member 6 (THEM6) as a marker of ADT resistance in PCa. THEM6 deletion reduces in vivo tumour growth and restores castration sensitivity in orthograft models of CRPC. Mechanistically, we show that the ER membrane-associated protein THEM6 regulates intracellular levels of ether lipids and is essential to trigger the induction of the ER stress response (UPR). Consequently, THEM6 loss in CRPC cells significantly alters ER function, reducing de novo sterol biosynthesis and preventing lipid-mediated activation of ATF4. Finally, we demonstrate that high THEM6 expression is associated with poor survival and correlates with high levels of UPR activation in PCa patients. Altogether, our results highlight THEM6 as a novel driver of therapy resistance in PCa as well as a promising target for the treatment of CRPC.

Limited surface impacts of the January 2021 sudden stratospheric warming

Subseasonal weather prediction can reduce economic disruption and loss of life, especially during “windows of opportunity” when noteworthy events in the Earth system are followed by characteristic weather patterns. Sudden stratospheric warmings (SSWs), breakdowns of the winter stratospheric polar vortex, are one such event. They often precede warm temperatures in Northern Canada and cold, stormy weather throughout Europe and the United States - including the most recent SSW on January 5th, 2021. Here we assess the drivers of surface weather in the weeks following the SSW through initial condition “scrambling” experiments using the real-time CESM2(WACCM6) Earth system prediction framework. We find that the SSW itself had a limited impact, and that stratospheric polar vortex stretching and wave reflection had no discernible contribution to the record cold in North America in February. Instead, the tropospheric circulation and bidirectional coupling between the troposphere and stratosphere were dominant contributors to variability.

Experimental forecasts show that a disturbed stratospheric polar vortex was not to blame for the deadly North American cold air outbreak in February 2021 - but it may have acted to sustain weather patterns and increase predictability in early 2021.

The association between tumour sidedness, clinicopathological characteristics and outcomes in patients undergoing curative resection for colon cancer

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Background: Right-sided colon cancer is associated with worse outcomes than left-sided disease, likely due to an association between tumour/host factors and tumour sidedness. The present study analyses the association between tumour sidedness, clinicopathological features and common mutations to better understand this discrepancy in outcomes. Methods: The association between tumour sidedness, clinicopathological characteristics and survival was examined within a cohort of patients undergoing curative surgery for TNM I-III colon cancer. Results: 3,419 patients were identified. 54% of cases were right-sided and associated with worse 3-year OS/CSS. On multivariate analysis for clinical factors: sex (OR 0.63), Systemic Inflammatory Grade (SIG), anaemia and differentiation (OR 0.80/0.31/0.57) were associated with T3 cancer sidedness and: sex, anaemia and differentiation (OR 0.61/0.46/0.57) were associated with T4 cancer sidedness. On further MVA including mutational factors anaemia/BRAF status remained significant in T3/T4 cancer respectively (OR 0.08/0.09). BRAF mutant status was associated with SIG in all patients/T3 disease (p=0.046/0.016). Conclusions: Worse outcomes seen in right-sided colon cancer are likely explained predominantly by factors including tumour stage, SIG, anaemia and BRAF mutational status. BRAF mutations are associated with the Systemic Inflammatory Response and further research is required to better understand this relationship taking into the tumour microenvironment, microsatellite instability.[Table: see text]