Spatially confined sub-tumor microenvironments in pancreatic cancer.

Intratumoral heterogeneity is a critical frontier in understanding how the tumor microenvironment (TME) propels malignant progression. Here, we deconvolute the human pancreatic TME through large-scale integration of histology-guided regional multiOMICs with clinical data and patient-derived preclinical models. We discover "subTMEs," histologically definable tissue states anchored in fibroblast plasticity, with regional relationships to tumor immunity, subtypes, differentiation, and treatment response. "Reactive" subTMEs rich in complex but functionally coordinated fibroblast communities were immune hot and inhabited by aggressive tumor cell phenotypes. The matrix-rich "deserted" subTMEs harbored fewer activated fibroblasts and tumor-suppressive features yet were markedly chemoprotective and enriched upon chemotherapy. SubTMEs originated in fibroblast differentiation trajectories, and transitory states were notable both in single-cell transcriptomics and in situ. The intratumoral co-occurrence of subTMEs produced patient-specific phenotypic and computationally predictable heterogeneity tightly linked to malignant biology. Therefore, heterogeneity within the plentiful, notorious pancreatic TME is not random but marks fundamental tissue organizational units.

Tryptophan-derived microbial metabolites activate the aryl hydrocarbon receptor in tumor-associated macrophages to suppress anti-tumor immunity.

The aryl hydrocarbon receptor (AhR) is a sensor of products of tryptophan metabolism and a potent modulator of immunity. Here, we examined the impact of AhR in tumor-associated macrophage (TAM) function in pancreatic ductal adenocarcinoma (PDAC). TAMs exhibited high AhR activity and Ahr-deficient macrophages developed an inflammatory phenotype. Deletion of Ahr in myeloid cells or pharmacologic inhibition of AhR reduced PDAC growth, improved efficacy of immune checkpoint blockade, and increased intra-tumoral frequencies of IFNγ+CD8+ T cells. Macrophage tryptophan metabolism was not required for this effect. Rather, macrophage AhR activity was dependent on Lactobacillus metabolization of dietary tryptophan to indoles. Removal of dietary tryptophan reduced TAM AhR activity and promoted intra-tumoral accumulation of TNFα+IFNγ+CD8+ T cells; provision of dietary indoles blocked this effect. In patients with PDAC, high AHR expression associated with rapid disease progression and mortality, as well as with an immune-suppressive TAM phenotype, suggesting conservation of this regulatory axis in human disease.

Characterizing the burden of biliary tract cancers across 28 hospitals in Ontario, Canada.

BACKGROUND AND AIMS: The incidence of biliary tract cancers (BTC) appears to be increasing worldwide. We analyzed the characteristics of BTC-related hospitalizations under medical services across 28 hospitals in Ontario, Canada. METHODS: This study uses data collected by GEMINI, a hospital research data network. BTC-related hospitalizations from 2015 to 2021 under the Department of Medicine or intensive care unit were captured using the International Classification of Diseases, 10th revision, codes for intrahepatic cholangiocarcinoma (iCCA), extrahepatic cholangiocarcinoma, and gallbladder cancers. RESULTS: A total of 4596 BTC-related hospitalizations (2720 iCCA, 1269 extrahepatic cholangiocarcinoma, 607 gallbladder cancers) were analyzed. The number of unique patients with BTC-related hospitalizations increased over time. For iCCA-related hospitalizations, the total number of hospitalizations increased (from 385 in 2016 to 420 in 2021, p = .005), the hospital length of stay decreased over the study period (mean 10 days [SD, 12] in 2016 to 9 days [SD, 8] in 2021, p = .04), and the number of in-hospital deaths was stable (from 68 [18%] in 2016 to 55 [13%] in 2021, p = .62). Other outcomes such as 30-day readmissions, medical imaging tests, intensive care unit-specific hospitalizations, and length of stay were stable over time for all cohorts. The cost of hospitalization for the BTC cohort increased from median $8203 CAD (interquartile range, 5063-15,543) in 2017 to $8507 CAD (interquartile range, 5345-14,755) in 2021. CONCLUSIONS: This real-world data analysis showed a rising number of patients with BTC-related hospitalizations and rising number of iCCA-related hospitalizations across 28 hospitals in Ontario between 2015 and 2021.

Adjuvant and neoadjuvant therapies for hepatocellular carcinoma.

Immune-oncology-based regimens have shown efficacy in advanced HCC and have been implemented as standard of care as first-line therapy. Their efficacy, including high response rates, and safety justify their evaluation in earlier disease stages. Following negative results for adjuvant sorafenib in the global STORM trial in 2015, 4 global phase 3 trials, featuring different immune checkpoint inhibitor combinations, entered in parallel the race in the adjuvant setting. The IMbrave050 trial, comparing adjuvant atezolizumab in combination with bevacizumab to active surveillance following curative-intent resection or ablation, was the first to report, fast-tracking the results of the first interim analysis and demonstrating an improvement in recurrence-free survival. The trial has provoked a discussion on the horizon of expectations from adjuvant treatment and the clinical relevance of efficacy endpoints. Moreover, major pathological responses reported from early phase 2 data in the neoadjuvant setting provide a strong rationale for the evaluation of these concepts in phase 3 trials. In this review, we summarize current evidence and outline future directions for systemic therapies in early-stage HCC.

Assessing circulating tumour DNA (ctDNA) as a prognostic biomarker in locally advanced rectal cancer: a systematic review and meta-analysis.

INTRODUCTION: Circulating tumour DNA (ctDNA) has emerged as a promising biomarker in various cancer types, including locally advanced rectal cancer (LARC), offering potential insights into disease progression, treatment response and recurrence. This review aims to comprehensively evaluate the utility of ctDNA as a prognostic biomarker in LARC. METHODS: PubMed, EMBASE and Web of Science were searched as part of our review. Studies investigating the utility of ctDNA in locally advanced rectal cancer (LARC) were assessed for eligibility. Quality assessment of included studies was performed using the Newcastle Ottawa Scale (NOS) risk of bias tool. Outcomes extracted included basic participant characteristics, ctDNA details and survival data. A meta-analysis was performed on eligible studies to determine pooled recurrence-free survival (RFS). RESULTS: Twenty-two studies involving 1676 participants were included in our analysis. Methodological quality categorised by the Newcastle Ottawa Scale was generally satisfactory across included studies. ctDNA detected at various time intervals was generally associated with poor outcomes across included studies. Meta-analysis demonstrated a pooled hazard ratio of 8.87 (95% CI 4.91-16.03) and 15.15 (95% CI 8.21-27.95), indicating an increased risk of recurrence with ctDNA positivity in the post-neoadjuvant and post-operative periods respectively. CONCLUSION: Our systematic review provides evidence supporting the prognostic utility of ctDNA in patients with LARC, particularly in identifying patients at higher risk of disease recurrence in the post-neoadjuvant and post-operative periods.

Sensitive tumour detection and classification using plasma cell-free DNA methylomes.

The use of liquid biopsies for cancer detection and management is rapidly gaining prominence1. Current methods for the detection of circulating tumour DNA involve sequencing somatic mutations using cell-free DNA, but the sensitivity of these methods may be low among patients with early-stage cancer given the limited number of recurrent mutations2-5. By contrast, large-scale epigenetic alterations-which are tissue- and cancer-type specific-are not similarly constrained6 and therefore potentially have greater ability to detect and classify cancers in patients with early-stage disease. Here we develop a sensitive, immunoprecipitation-based protocol to analyse the methylome of small quantities of circulating cell-free DNA, and demonstrate the ability to detect large-scale DNA methylation changes that are enriched for tumour-specific patterns. We also demonstrate robust performance in cancer detection and classification across an extensive collection of plasma samples from several tumour types. This work sets the stage to establish biomarkers for the minimally invasive detection, interception and classification of early-stage cancers based on plasma cell-free DNA methylation patterns.

Assessing Circulating Tumour DNA (ctDNA) as a Biomarker for Anal Cancer Management: A Systematic Review.

This systematic review investigates the potential of circulating tumour DNA (ctDNA) as a predictive biomarker in the management and prognosis of squamous cell carcinoma of the anal canal (SCCA). PubMed, EMBASE, and Cochrane Central Registry of Controlled Trials were searched until 7 January 2024. Selection criteria included research articles exploring ctDNA in the context of anal cancer treatment response, recurrence risk assessment, and consideration of salvage surgery. A total of eight studies were therefore included in the final review, examining a total of 628 patients. These studies focused on three main themes: SCCA diagnosis and staging, treatment response, and patient outcomes. Significant heterogeneity was observed in terms of patient cohort, study methodology, and ctDNA biomarkers. Four studies provided information on the sensitivity of ctDNA biomarkers in SCCA, with a range of 82-100%. Seven studies noted a correlation between pre-treatment ctDNA levels and SCCA disease burden, suggesting that ctDNA could play a role as a biomarker for the staging of SCCA. Across all seven studies with paired pre- and post-treatment ctDNA samples, a trend was seen towards decreasing ctDNA levels post-treatment, with specific identification of a 'fast elimination' group who achieve undetectable ctDNA levels prior to the end of treatment and may be less likely to experience treatment failure. Residual ctDNA detection post-treatment was associated with poorer patient prognosis. This systematic review identifies the broad potential of ctDNA as a useful and decisive tool in the management of SCCA. Further analysis of ctDNA biomarkers that include larger patient cohorts is required in order to clearly evaluate their potential role in clinical decision-making processes.

Liver transplantation for intrahepatic cholangiocarcinoma: who, when and how.

PURPOSE OF REVIEW: Using transplant oncology principles, selected patients with intrahepatic cholangiocarcinoma (iCCA) may achieve long-term survival after liver transplantation. Strategies for identifying and managing these patients are discussed in this review. RECENT FINDINGS: Unlike initial reports, several modern series have reported positive outcomes after liver transplantation for iCCA. The main challenges are in identifying the appropriate candidates and graft scarcity. Tumor burden and response to neoadjuvant therapies have been successfully used to identify favorable biology in unresectable cases. New molecular biomarkers will probably predict this response in the future. Also, new technologies and better strategies have been used to increase graft availability for these patients without affecting the liver waitlist. SUMMARY: Liver transplantation for the management of patients with unresectable iCCA is currently a reality under strict research protocols. Who is a candidate for transplantation, when to use neoadjuvant and locoregional therapies, and how to increase graft availability are the main topics of this review.

Systemic inflammatory prognostic scores in advanced pancreatic adenocarcinoma.

BACKGROUND: Systemic inflammatory scores may aid prognostication and patient selection for trials. We compared five scores in advanced pancreatic adenocarcinoma (PDAC). METHODS: Unresectable/metastatic PDAC patients enrolled in the Comprehensive Molecular Characterisation of Advanced Pancreatic Ductal Adenocarcinoma for Better Treatment Selection trial (NCT02750657) were included. Patients had pre-treatment biopsies for whole genome and RNA sequencing. CD8 immunohistochemistry was available in a subset. The neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio, Prognostic Nutritional Index, Gustave Roussy Immune Score (GRIm-S), and Memorial Sloan Kettering Prognostic Score (MPS) were calculated. Overall survival (OS) was estimated using Kaplan-Meier methods. Associations between inflammatory scores, clinical/genomic characteristics, and OS were analysed. RESULTS: We analysed 263 patients. High-risk NLR, GRIm-S and MPS were poorly prognostic. The GRIm-S had the highest predictive ability: median OS 6.4 vs. 10 months for high risk vs. low-risk (P < 0.001); HR 2.26 (P < 0.001). ECOG ≥ 1, the basal-like subtype, and low-HRDetect were additional poor prognostic factors (P < 0.01). Inflammatory scores did not associate with RNA-based classifiers or homologous recombination repair deficiency genotypes. High-risk MPS (P = 0.04) and GRIm-S (P = 0.02) patients had lower median CD8 + tumour-infiltrating lymphocytes. CONCLUSIONS: Inflammatory scores incorporating NLR have prognostic value in advanced PDAC. Understanding immunophenotypes of poor-risk patients and using these scores in trials will advance the field.

Comparison of Four Clinical Prognostic Scores in Patients with Advanced Gastric and Esophageal Cancer.

BACKGROUND: Prognostic scores that can identify patients at risk for early death are needed to aid treatment decision-making and patient selection for clinical trials. We compared the accuracy of four scores to predict early death (within 90 days) and overall survival (OS) in patients with metastatic gastric and esophageal (GE) cancer. METHODS: Advanced GE cancer patients receiving first-line systemic therapy were included. Prognostic risks were calculated using: Royal Marsden Hospital (RMH), MD Anderson Cancer Centre (MDACC), Gustave Roussy Immune (GRIm-Score), and MD Anderson Immune Checkpoint Inhibitor (MDA-ICI) scores. Overall survival (OS) was estimated using the Kaplan-Meier method. Cox proportional hazards models were used to analyze associations between prognostic scores and OS. The predictive discrimination was estimated using Harrell's c-index. Predictive ability for early death was measured using time-dependent AUCs. RESULTS: In total, 451 patients with metastatic GE cancer were included. High risk patients had shorter OS for all scores (RMH high- vs. low-risk median OS 7.9 vs. 12.2 months, P < .001; MDACC 6.8 vs. 11.9 months P < .001; GRIm-Score 5.3 vs. 13 months, P < .001; MDA-ICI 8.2 vs. 12.2 months, P < .001). On multivariable analysis, each prognostic score was significantly associated with OS. The GRIm-Score had the highest predictive discrimination and predictive ability for early death. CONCLUSIONS: The GRIm-Score had the highest accuracy in predicting early death and OS. Clinicians may use this score to identify patients at higher risk of early death to guide treatment decisions including clinical trial enrolment. This score could also be used as a stratification factor in future clinical trial designs.

Dynamic risk profiling of HCC recurrence after curative intent liver resection.

BACKGROUND AND AIMS: Following liver resection (LR) for HCC, the likelihood of survival is dynamic, in that multiple recurrences and/or metastases are possible, each having variable impacts on outcomes. We sought to evaluate the natural progression, pattern, and timing of various disease states after LR for HCC using multistate modeling and to create a practical calculator to provide prognostic information for patients and clinicians. APPROACH AND RESULTS: Adult patients undergoing LR for HCC between January 2000 and December 2018 were retrospectively identified at a single center. Multistate analysis modeled post-LR tumor progression by describing transitions between distinct disease states. In this model, the states included surgery, intrahepatic recurrence (first, second, third, fourth, fifth), distant metastasis with or without intrahepatic recurrence, and death. Of the 486 patients included, 169 (34.8%) remained recurrence-free, 205 (42.2%) developed intrahepatic recurrence, 80 (16.5%) developed distant metastasis, and 32 (7%) died. For an average patient having undergone LR, there was a 33.1% chance of remaining disease-free, a 31.0% chance of at least one intrahepatic recurrence, a 16.3% chance of distant metastasis, and a 19.8% chance of death within the first 60 months post-LR. The transition probability from surgery to first intrahepatic recurrence, without a subsequent state transition, increased from 3% (3 months) to 17.4% (30 months) and 17.2% (60 months). Factors that could modify these probabilities included tumor size, satellite lesions, and microvascular invasion. The online multistate model calculator can be found on https://multistatehcc.shinyapps.io/home/. CONCLUSIONS: In contrast to standard single time-to-event estimates, multistate modeling provides more realistic prognostication of outcomes after LR for HCC by taking into account many postoperative disease states and transitions between them. Our multistate modeling calculator can provide meaningful data to guide the management of patients undergoing postoperative surveillance and therapy.

Optimizing Circulating Tumour DNA Use in the Perioperative Setting for Intrahepatic Cholangiocarcinoma: Diagnosis, Screening, Minimal Residual Disease Detection and Treatment Response Monitoring.

In this review, we present the current evidence and future perspectives on the use of circulating tumour DNA (ctDNA) in the diagnosis, management and understanding the prognosis of patients with intrahepatic cholangiocarcinoma (iCCA) undergoing surgery. Liquid biopsies or ctDNA maybe utilized to: (1) determine the molecular profile of the tumour and therefore guide the selection of molecular targeted therapy in the neoadjuvant setting, (2) form a surveillance tool for the detection of minimal residual disease or cancer recurrence after surgery, and (3) diagnose and screen for early iCCA detection in high-risk populations. The potential for ctDNA can be tumour-informed or -uninformed depending on the goals of its use. Future studies will require ctDNA extraction technique validations, with standardizations of both the platforms and the timing of ctDNA collections.

Randomised, Phase II study of selumetinib, an oral inhibitor of MEK, in combination with cisplatin and gemcitabine chemotherapy for patients with advanced biliary tract cancer.

INTRODUCTION: Cisplatin and gemcitabine (CisGem) are standard chemotherapy for advanced biliary tract cancer (BTC). The MEK inhibitor selumetinib showed synergy with gemcitabine when administered sequentially in BTC. This randomised Phase 2 trial aimed to assess the efficacy of sequential or continuous selumetinib with CisGem. METHODS: Patients with advanced BTC received CisGem; arm A included selumetinib every day, arm B: selumetinib, days 1-5, 8-19 each cycle. Arm C received CisGem alone. Selumetinib was dosed at 75 mg BID but amended to 50 mg BID due to toxicity. RESULTS: In all, 51 participants were evaluable for response. No significant difference was seen in mean change in tumour size at 10 weeks between arms A and C (-7.8% vs -12.8%, P = 0.54) or arms B and C (-15% vs -12.8%, P = 0.78). There was no difference in median progression-free survival (6.0, 7.0, 6.3 months, P > 0.95) or overall survival (11.7, 11.7, 12.8 months, P = 0.70) for arms A, B and C, respectively. More participants experienced grade 3-4 toxicities in selumetinib-containing arms. More participants in arm A required chemotherapy dose reductions (P = 0.01) with lower chemotherapy dose intensity during the first 10 weeks. CONCLUSION: Adding sequential or continuous selumetinib to CisGem failed to improve efficacy and increased toxicity in patients with advanced BTC.

Genomic Features and Classification of Homologous Recombination Deficient Pancreatic Ductal Adenocarcinoma.

BACKGROUND AND AIMS: Homologous recombination deficiency (HRD) in pancreatic ductal adenocarcinoma (PDAC), remains poorly defined beyond germline (g) alterations in BRCA1, BRCA2, and PALB2. METHODS: We interrogated whole genome sequencing (WGS) data on 391 patients, including 49 carriers of pathogenic variants (PVs) in gBRCA and PALB2. HRD classifiers were applied to the dataset and included (1) the genomic instability score (GIS) used by Myriad's MyChoice HRD assay; (2) substitution base signature 3 (SBS3); (3) HRDetect; and (4) structural variant (SV) burden. Clinical outcomes and responses to chemotherapy were correlated with HRD status. RESULTS: Biallelic tumor inactivation of gBRCA or PALB2 was evident in 43 of 49 germline carriers identifying HRD-PDAC. HRDetect (score ≥0.7) predicted gBRCA1/PALB2 deficiency with highest sensitivity (98%) and specificity (100%). HRD genomic tumor classifiers suggested that 7% to 10% of PDACs that do not harbor gBRCA/PALB2 have features of HRD. Of the somatic HRDetecthi cases, 69% were attributed to alterations in BRCA1/2, PALB2, RAD51C/D, and XRCC2, and a tandem duplicator phenotype. TP53 loss was more common in BRCA1- compared with BRCA2-associated HRD-PDAC. HRD status was not prognostic in resected PDAC; however in advanced disease the GIS (P = .02), SBS3 (P = .03), and HRDetect score (P = .005) were predictive of platinum response and superior survival. PVs in gATM (n = 6) or gCHEK2 (n = 2) did not result in HRD-PDAC by any of the classifiers. In 4 patients, BRCA2 reversion mutations associated with platinum resistance. CONCLUSIONS: Germline and parallel somatic profiling of PDAC outperforms germline testing alone in identifying HRD-PDAC. An additional 7% to 10% of patients without gBRCA/PALB2 mutations may benefit from DNA damage response agents.

Is Biannual Surveillance for Pancreatic Cancer Sufficient in Individuals With Genetic Syndromes or Familial Pancreatic Cancer?

BACKGROUND: Individuals with a family history of pancreatic adenocarcinoma (PC) or with a germline mutation in a PC susceptibility gene are at increased risk of developing PC. These high-risk individuals (HRIs) may benefit from PC surveillance. METHODS: A PC surveillance program was developed to evaluate the detection of premalignant lesions and early-stage PCs using biannual imaging and to determine whether locally advanced or metastatic PCs develop despite biannual surveillance. From January 2013 to April 2020, asymptomatic HRIs were enrolled and followed with alternating MRI and endoscopic ultrasound every 6 months. RESULTS: Of 75 HRIs, 43 (57.3%) had a germline mutation in a PC susceptibility gene and 32 (42.7%) had a familial pancreatic cancer (FPC) pedigree. Branch-duct intraductal papillary mucinous neoplasms (BD-IPMNs) were identified in 26 individuals (34.7%), but only 2 developed progressive lesions. One patient with Peutz-Jeghers syndrome (PJS) developed locally advanced PC arising from a BD-IPMN. Whole-genome sequencing of this patient's PC and of a second patient with PJS-associated PC from the same kindred revealed biallelic inactivation of STK11 in a KRAS-independent manner. A review of 3,853 patients from 2 PC registries identified an additional patient with PJS-associated PC. All 3 patients with PJS developed advanced PC consistent with the malignant transformation of an underlying BD-IPMN in <6 months. The other surveillance patient with a progressive lesion had FPC and underwent resection of a mixed-type IPMN that harbored polyclonal KRAS mutations. CONCLUSIONS: PC surveillance identifies a high prevalence of BD-IPMNs in HRIs. Patients with PJS with BD-IPMNs may be at risk for accelerated malignant transformation.

Correlation of transcriptional subtypes with a validated CT radiomics score in resectable pancreatic ductal adenocarcinoma.

OBJECTIVES: Transcriptional classifiers (Bailey, Moffitt and Collison) are key prognostic factors of pancreatic ductal adenocarcinoma (PDAC). Among these classifiers, the squamous, basal-like, and quasimesenchymal subtypes overlap and have inferior survival. Currently, only an invasive biopsy can determine these subtypes, possibly resulting in treatment delay. This study aimed to investigate the association between transcriptional subtypes and an externally validated preoperative CT-based radiomic prognostic score (Rad-score). METHODS: We retrospectively evaluated 122 patients who underwent resection for PDAC. All treatment decisions were determined at multidisciplinary tumor boards. Tumor Rad-score values from preoperative CT were dichotomized into high or llow categories. The primary endpoint was the correlation between the transcriptional subtypes and the Rad-score using multivariable linear regression, adjusting for clinical and histopathological variables (i.e., tumor size). Prediction of overall survival (OS) was secondary endpoint. RESULTS: The Bailey transcriptional classifier significantly associated with the Rad-score (coefficient = 0.31, 95% confidence interval [CI]: 0.13-0.44, p = 0.001). Squamous subtype was associated with high Rad-scores while non-squamous subtype was associated with low Rad-scores (adjusted p = 0.03). Squamous subtype and high Rad-score were both prognostic for OS at multivariable analysis with hazard ratios (HR) of 2.79 (95% CI: 1.12-6.92, p = 0.03) and 4.03 (95% CI: 1.42-11.39, p = 0.01), respectively. CONCLUSIONS: In patients with resectable PDAC, an externally validated prognostic radiomic model derived from preoperative CT is associated with the Bailey transcriptional classifier. Higher Rad-scores were correlated with the squamous subtype, while lower Rad-scores were associated with the less lethal subtypes (immunogenic, ADEX, pancreatic progenitor). KEY POINTS: • The transcriptional subtypes of PDAC have been shown to have prognostic importance but they require invasive biopsy to be assessed. • The Rad-score radiomic biomarker, which is obtained non-invasively from preoperative CT, correlates with the Bailey squamous transcriptional subtype and both are negative prognostic biomarkers. • The Rad-score is a promising non-invasive imaging biomarker for personalizing neoadjuvant approaches in patients undergoing resection for PDAC, although additional validation studies are required.

Clinical and genomic characterisation of mismatch repair deficient pancreatic adenocarcinoma.

OBJECTIVE: To describe the clinical, pathological and genomic characteristics of pancreatic cancer with DNA mismatch repair deficiency (MMRD) and proficiency (MMRP). DESIGN: We identified patients with MMRD and MMRP pancreatic cancer in a clinical cohort (N=1213, 519 with genetic testing, 53 with immunohistochemistry (IHC)) and a genomic cohort (N=288 with whole-genome sequencing (WGS)). RESULTS: 12 out of 1213 (1.0%) in the clinical cohort were MMRD by IHC or WGS. Of the 14 patients with Lynch syndrome, 3 (21.4%) had an MMRP pancreatic cancer by IHC, and 4 (28.6%) were excluded because tissue was unavailable for testing. MMRD cancers had longer overall survival after surgery (weighted HR after coarsened exact matching 0.11, 95% CI 0.02 to 0.78, p=0.001). One patient with an unresectable MMRD cancer has an ongoing partial response 3 years after starting treatment with PD-L1/CTLA-4 inhibition. This tumour showed none of the classical histopathological features of MMRD. 9 out of 288 (3.1%) tumours with WGS were MMRD. Despite markedly higher tumour mutational burden and neoantigen loads, MMRD cancers were significantly less likely to have mutations in usual pancreatic cancer driver genes like KRAS and SMAD4, but more likely to have mutations in genes that drive cancers with microsatellite instability like ACV2RA and JAK1. MMRD tumours were significantly more likely to have a basal-like transcriptional programme and elevated transcriptional markers of immunogenicity. CONCLUSIONS: MMRD pancreatic cancers have distinct clinical, pathological and genomic profiles. Patients with MMRD pancreatic cancer should be considered for basket trials targeting enhanced immunogenicity or the unique genomic drivers in these malignancies.

Neoadjuvant therapy versus direct to surgery for T4 colon cancer: meta-analysis.

BACKGROUND: Despite persistently poor oncological outcomes, approaches to the management of T4 colonic cancer remain variable, with the role of neoadjuvant therapy unclear. The aim of this review was to compare oncological outcomes between direct-to-surgery and neoadjuvant therapy approaches to T4 colon cancer. METHODS: A librarian-led systematic search of MEDLINE, Embase, the Cochrane Library, Web of Science, and CINAHL up to 11 February 2020 was performed. Inclusion criteria were primary research articles comparing oncological outcomes between neoadjuvant therapies or direct to surgery for primary T4 colonic cancer. Based on PRISMA guidelines, screening and data abstraction were undertaken in duplicate. Quality assessment was carried out using Cochrane risk-of-bias tools. Random-effects models were used to pool effect estimates. This study compared pathological resection margins, postoperative morbidity, and oncological outcomes of cancer recurrence and overall survival. RESULTS: Four studies with a total of 43 063 patients met the inclusion criteria. Compared with direct to surgery, neoadjuvant therapy was associated with increased rates of margin-negative resection (odds ratio (OR) 2.60, 95 per cent c.i. 1.12 to 6.02; n = 15 487) and 5-year overall survival (pooled hazard ratio 1.42, 1.10 to 1.82, I2 = 0 per cent; n = 15 338). No difference was observed in rates of cancer recurrence (OR 0.42, 0.15 to 1.22; n = 131), 30-day minor (OR 1.12, 0.68 to 1.84; n = 15 488) or major (OR 0.62, 0.27 to 1.44; n = 15 488) morbidity, or rates of treatment-related adverse effects. CONCLUSION: Compared with direct to surgery, neoadjuvant therapy improves margin-negative resection rates and overall survival.

Prognostic value of early changes in CT-measured body composition in patients receiving chemotherapy for unresectable pancreatic cancer.

OBJECTIVES: Skeletal muscle mass is a prognostic factor in pancreatic ductal adenocarcinoma (PDAC). However, it remains unclear whether changes in body composition provide an incremental prognostic value to established risk factors, especially the Response Evaluation Criteria in Solid Tumors version 1.1 (RECISTv1.1). The aim of this study was to determine the prognostic value of CT-quantified body composition changes in patients with unresectable PDAC starting chemotherapy. METHODS: We retrospectively evaluated 105 patients with unresectable (locally advanced or metastatic) PDAC treated with FOLFIRINOX (n = 64) or gemcitabine-based (n = 41) first-line chemotherapy within a multicenter prospective trial. Changes (Δ) in skeletal muscle index (SMI), subcutaneous (SATI), and visceral adipose tissue index (VATI) between pre-chemotherapy and first follow-up CT were assessed. Cox regression models and covariate-adjusted survival curves were used to identify predictors of overall survival (OS). RESULTS: At multivariable analysis, adjusting for RECISTv1.1-response at first follow-up, ΔSMI was prognostic for OS with a hazard ratio (HR) of 1.2 (95% CI: 1.08-1.33, p = 0.001). No significant association with OS was observed for ΔSATI (HR: 1, 95% CI: 0.97-1.04, p = 0.88) and ΔVATI (HR: 1.01, 95% CI: 0.99-1.04, p = 0.33). At an optimal cutoff of 2.8 cm2/m2 per 30 days, the median survival of patients with high versus low ΔSMI was 143 versus 233 days (p < 0.001). CONCLUSIONS: Patients with a lower rate of skeletal muscle loss at first follow-up demonstrated improved survival for unresectable PDAC, regardless of their RECISTv1.1-category. Assessing ΔSMI at the first follow-up CT may be useful for prognostication, in addition to routine radiological assessment. KEY POINTS: • In patients with unresectable pancreatic ductal adenocarcinoma, change of skeletal muscle index (ΔSMI) in the early phase of chemotherapy is prognostic for overall survival, even after adjusting for Response Evaluation Criteria in Solid Tumors version 1.1 (RECISTv1.1) assessment at first follow-up. • Changes in adipose tissue compartments at first follow-up demonstrated no significant association with overall survival. • Integrating ΔSMI into routine radiological assessment may improve prognostic stratification and impact treatment decision-making at the first follow-up.

The impact of symptoms and comorbidity on health utility scores and health-related quality of life in small cell lung cancer using real world data.

PURPOSE: Small cell lung cancer (SCLC) is a highly fatal disease associated with significant morbidity, with a need for real-world symptom and health utility score (HUS) data. HUS can be measured using an EQ-5D-5L questionnaire, however most captured data is available in non-SCLC (NSCLC) only. As new treatment regimens become available in SCLC it becomes important to understand factors which influence health-related quality of life and health utility. METHODS: A prospective observational cohort study (2012-2017) of ambulatory histologically confirmed SCLC evaluated patient-reported EQ-5D-5L-derived HUS, toxicity and symptoms. A set of NSCLC patients was used to compare differential factors affecting HUS. Clinical and demographic factors were evaluated for differential interactions between lung cancer types. Comorbidity scores were documented for each patient. RESULTS: In 75 SCLC and 150 NSCLC patients, those with SCLC had lower mean HUS ((SCLC vs NSCLC: mean 0.69 vs 0.79); (p < 0.001)) when clinically stable and with progressive disease: ((SCLC mean HUS = 0.60 vs NSCLC mean HUS = 0.77), (p = 0.04)). SCLC patients also had higher comorbidity scores ((1.11 vs 0.73); (p < 0.015)). In multivariable analyses, increased symptom severity and comorbidity scores decreased HUS in both SCLC and NSCLC (p < 0.001); however, only comorbidity scores differentially affected HUS (p < 0.0001), with a greater reduction of HUS adjusted per unit of comorbidity in SCLC. CONCLUSION: Patients with advanced SCLC had significantly lower HUS than NSCLC. Both patient cohorts are impacted by symptoms and comorbidity, however, comorbidity had a greater negative effect in SCLC patients.