Pan-Asian adapted ESMO consensus guidelines for the management of patients with metastatic colorectal cancer: a JSMO-ESMO initiative endorsed by CSCO, KACO, MOS, SSO and TOS

Emerging roles of mesenchymal stem cell-derived exosomes in gastrointestinal cancers

Gastrointestinal tumours are the most common solid tumours, with a poor prognosis and remain a major challenge in cancer treatment. Mesenchymal stem cells (MSC) are multipotent stromal cells with the potential to differentiate into multiple cell types. Several studies have shown that MSC-derived exosomes have become essential regulators of intercellular communication in a variety of physiological and pathological processes. Notably, MSC-derived exosomes support or inhibit tumour progression in different cancers through the delivery of proteins, RNA, DNA, and bioactive lipids. Herein, we summarise current advances in MSC-derived exosomes in cancer research, with particular reference to their role in gastrointestinal tumour development. MSC-derived exosomes are expected to be a novel potential strategy for the treatment of gastrointestinal cancers.

Efficacy of Immune Checkpoint Inhibitors in Patients with Mismatch Repair-Deficient or Microsatellite Instability-High Metastatic Colorectal Cancer: Analysis of Three Phase-II Trials

Programmed cell death ligand 1 (PD-L1) and programmed cell death protein 1 (PD-1) inhibitors are increasingly used in a variety of solid tumors. In patients with DNA mismatch repair-deficient (dMMR)/microsatellite instability-high (MSI-H) metastatic colorectal cancer, their efficacy has been demonstrated in recently published phase-II trials. However, an indirect comparison of effectiveness between pembrolizumab, nivolumab, and nivolumab+ipilimumab is not yet available.

After a standard literature search, we analyzed four overall survival (OS) curves from three phase-II trials. Individual patient data were reconstructed from each curve using a specific web-based technique (Shiny method). Indirect statistical comparisons were made based on hazard ratio (HR) and restricted mean survival time (RMST).

Nivolumab+ipilumumab had a better HR compared with pembrolizumab (0.65, 95% confidence interval [CI], 0.43 to 1.002, p=0.051); the difference being close to statistical significance. In the analysis based on RMST, the combination of nivolumab+ipilimumab showed a significantly longer OS than pembrolizumab (improvement in RMST, 1.08 mos; 95%CI, 0.11 to 2.06; p=0.029). The other two pairwise differences in RMST (nivolumab vs. pembrolizumab and nivolumab+ ipilimumab vs. nivolumab) had a smaller magnitude (0.25 mos, 95%CI, -0.99 to 1.48, and 0.84 mos, 95%CI, -0.40 to 2.07, respectively) and were far from statistical significance.

Our results favoring the combination of nivolumab+ipilimumab in metastatic colorectal cancer must be viewed with caution owing to the indirect nature of our statistical comparisons. With this limitation in mind, the magnitude of the incremental benefit for the above combination treatment was estimated to be around one month over a follow-up of 15 months.

Immunotherapy-Related Publications in Colorectal Cancer: A Bibliometric Analysis

Patients with microsatellite-instability-high (MSI-H) or mismatched repair-deficient colorectal cancer (CRC) appear to be responsive to checkpoint inhibitors. This study aimed to assess research trends in CRC immunotherapy. Publication patterns of articles covering immunotherapies in CRC in the Web of Science Core Collection database were retrospectively examined using VOS viewer software (version 1.6.16) prior to 25 May 2021. Ultimately, 3977 records were identified that were published between 1975 and 2021, which received a total of 128,681 citations (an average of 32.36 citations per item), with a noticeable rise in 2014. The majority of articles were published in the US (35.8%), China (17.7%), and Germany (9.4%). Publications mainly originated from the Institut National de la Santé Et De La Recherche Medicale Inserm, followed by the University of Texas System and Harvard University; however, Johns Hopkins University received the most citations (18,666 for 69 publications). The Journal of Clinical Oncology issued the most publications (n = 146), while the most referenced item (7724 citations) was published in the New England Journal of Medicine in 2012. The most common keywords were associated with tumors (expression and microsatellite instability) or immune system components (t-cells/dendritic cells). The findings demonstrate the scientific community’s interest in the MSI-H subtype of colorectal tumors and how immunotherapy may be employed more successfully to treat metastatic CRC.

A modified MethyLight assay predicts the clinical outcomes of anti-EGFR treatment in metastatic colorectal cancer

DNA methylation status correlates with clinical outcomes of anti‐epidermal growth factor receptor (EGFR) treatment. There is a strong need to develop a simple assay for measuring DNA methylation status for the clinical application of drug selection based on it. In this study, we collected data from 186 patients with metastatic colorectal cancer (mCRC) who had previously received anti‐EGFR treatment. We modified MethyLite to develop a novel assay to classify patients as having highly methylated colorectal cancer (HMCC) or low‐methylated colorectal cancer (LMCC) based on the methylation status of 16 CpG sites of tumor‐derived genomic DNA in the development cohort (n = 30). Clinical outcomes were then compared between the HMCC and LMCC groups in the validation cohort (n = 156). The results showed that HMCC had a significantly worse response rate (4.2% vs 33.3%; P = .004), progression‐free survival (median: 2.5 vs 6.6 mo, P < .001, hazard ratio [HR] = 0.22), and overall survival (median: 5.6 vs 15.5 mo, P < .001, HR = 0.23) than did LMCC in patients with RAS wild‐type mCRC who were refractory or intolerable to oxaliplatin‐ and irinotecan‐based chemotherapy (n = 101). The DNA methylation status was an independent predictive factor and a more accurate biomarker than was the primary site of anti‐EGFR treatment. In conclusion, our novel DNA methylation measurement assay based on MethyLight was simple and useful, suggesting its implementation as a complementary diagnostic tool in a clinical setting.

Combination therapy of capecitabine, irinotecan, oxaliplatin, and bevacizumab as a first-line treatment for metastatic colorectal cancer: Safety lead-in results from the QUATTRO-II study

Background FOLFOXIRI plus bevacizumab is the first-line treatment for metastatic colorectal cancer (mCRC) but demonstrates high neutropenia incidence among Asian patients. Hence, we conducted the randomized phase II QUATTRO-II study (ClinicalTrials.gov identifier: NCT04097444; Japan Registry of Clinical Trials identifier: jRTCs041190072) to evaluate the safety and efficacy of capecitabine, oxaliplatin, and irinotecan (CAPOXIRI) combination plus bevacizumab versus FOLFOXIRI plus bevacizumab, expecting a lower incidence of neutropenia without compromising the efficacy. Methods We investigated the recommended doses (RD) of oxaliplatin and irinotecan as a safety lead-in portion of Step 1 before initiating the randomized portion as Step 2. Four dose levels of CAPOXIRI (fixed dose of capecitabine, 1600 mg/m2; escalated/de-escalated doses of oxaliplatin and irinotecan) plus bevacizumab (7.5 mg/kg) were investigated in a 3 + 3 manner. A dose level of ≤ 2/6 of dose-limiting toxicity (DLT) cases was expected as the RD. Results In Step 1, we included nine patients (three and six in levels 0 and + 1, respectively). Level 0 (irinotecan, 200 mg/m2; oxaliplatin, 100 mg/m2) did not demonstrate DLTs. In level + 1 (irinotecan, 200 mg/m2; oxaliplatin, 130 mg/m2), although one patient experienced grade 4 febrile neutropenia, no further safety concerns were observed. As a preliminary efficacy result, the objective response rate in all nine patients was 89 % (100 and 83 % in levels 0 and + 1, respectively). Conclusions The RD of CAPOXIRI plus bevacizumab was 200, 130, and 1600 mg/m2 for irinotecan, oxaliplatin, and capecitabine, respectively, and 7.5 mg/kg for bevacizumab. The randomized portion is still ongoing.

Pan-Asian adapted ESMO Clinical Practice Guidelines for the diagnosis treatment and follow-up of patients with localised colon cancer

The most recent version of the European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of localised colon cancer was published in 2020. It was decided by both the ESMO and the Japanese Society of Medical Oncology (JSMO) to convene a special virtual guidelines meeting in March 2021 to adapt the ESMO 2020 guidelines to take into account the ethnic differences associated with the treatment of localised colon cancer in Asian patients. These guidelines represent the consensus opinions reached by experts in the treatment of patients with localised colon cancer representing the oncological societies of Japan (JSMO), China (CSCO), India (ISMPO), Korea (KSMO), Malaysia (MOS), Singapore (SSO) and Taiwan (TOS). The voting was based on scientific evidence and was independent of the current treatment practices and drug availability and reimbursement situations in the different Asian countries.

C677T and A1298C MTHFR gene polymorphisms and response to fluoropyrimidine-based chemotherapy in Mestizo patients with metastatic colorectal cancer

OBJECTIVE

To assess the association between C677T and A1298C methylenetetrahydrofolate reductase (MTHFR) single-nucleotide polymorphisms (SNPs) and response to first-line fluoropyrimidine-based chemotherapy for metastatic colorectal adenocarcinoma.

METHODS

A total of 68 patients were prospectively followed up in San Juan de Dios Hospital (San José, Costa Rica) from January 2019 to November 2020. Patients received first-line therapy with capecitabine or 5-fluorouracil in combination with oxaliplatin or irinotecan. Germline and somatic DNA was extracted from blood samples and paraffin-embedded tissue, respectively. Overall response rate (partial response + complete response) was assessed according to RECIST 1.1 criteria. Cox regression models were performed to identify the effect of MTHFR C677T and A1298C SNPs on progression-free survival (PFS) and overall survival (OS) (NCT registration number: 03852290).

RESULTS

Patients harboring one or both T alleles of the MTHFR C677T SNP had better overall response than homozygous wild-type individuals [odds ratio (OR): 3.21; 95% confidence interval (CI), 1.05-9.81; P = 0.03]. No association was found between the MTHFR A1298C genotypes and overall response (OR: 0.75; 95% CI, 0.26-2.20; P = 0.60). Patients with the MTHFR 677 TT and CT genotypes had longer PFS than CC individuals (hazard ratio: 0.53; 95% CI, 0.28-0.98; P = 0.045), even after adjustment for confounders (hazard ratio: 0.50; 95% CI, 0.25-0.98; P = 0.04). We found no association between the MTHFR A1298C SNP and PFS (hazard ratio: 1.35; 95% CI, 0.72-2.55; P = 0.34). None of the SNPs was associated with OS.

CONCLUSION

Patients carrying at least one mutant allele of the MTHFR C677T SNP had a better overall response and longer PFS than wild-type homozygous patients.

Triplet chemotherapy in combination with anti-EGFR agents for the treatment of metastatic colorectal cancer: Current evidence, advances, and future perspectives

Doublet or triplet chemotherapy regimens in combination with anti-epidermal growth factor receptor (anti-EGFR) monoclonal antibodies (mAb), such as cetuximab or panitumumab, or the anti-vascular endothelial growth factor mAb bevacizumab, are the current recommended standard of care therapies for unresectable metastatic colorectal cancer (mCRC). While the recommended dosing schedule for the triplet chemotherapy regimen with 5-fluorouracil, oxaliplatin and irinotecan (FOLFOXIRI) in combination with bevacizumab is well established, the optimal dosing of FOLFOXIRI in combination with anti-EGFR agents is unknown. Several randomized, phase 3 clinical trials of patients with mCRC have demonstrated improved survival and response rates with FOLFOXIRI, alone or when combined with bevacizumab, compared with doublet chemotherapy regimens. Trials of anti-EGFR agents in combination with FOLFOXIRI have also shown promising results. In this review, we summarize the emerging evidence regarding the safety and efficacy of anti-EGFR agents in combination with triplet chemotherapy regimens and discuss the potential for this combination as a future treatment option for patients with RAS-wild-type mCRC.

Predictive factors of survival of colorectal cancer patients after para-aortic lymph node metastasis

BACKGROUND

Para-aortic lymph node (PALN) metastasis is an ominous manifestation indicating a poor prognosis in colorectal cancer (CRC) patients; however, some treatments prolong survival. In this study, we investigated predictors of prolonged survival in CRC patients after PALN metastasis.

METHODS

We examined 141 patients with CRC that metastasized to the PALNs from CRC with or without extra-PALN metastasis. Among clinicopathological parameters, factors associated with survival after PALN metastasis were identified by multivariate analyses using Cox's proportional hazard models.

RESULTS

The mean hemoglobin and albumin values at diagnosis were 12.3 g/dL and 3.7 g/dL, respectively. Rectal cancer was predominant (n = 81). Mutated RAS was detected in 43%. One hundred and four patients had differentiated adenocarcinoma. Patients underwent PALN dissection (n = 11), radiotherapy (n = 6), and systemic therapy (n = 120). Biologics were administered to 95 patients. The median survival time was 29.1 months. On multivariate analysis, independent factors associated with reduced survival after PALN metastasis were low albumin (hazard ratio [HR] 2.33 per -1 g/dL), mutated RAS (HR 2.55), other than differentiated adenocarcinoma (HR 2.75), rectal cancer (HR 3.38 against right-sided colon, and 3.48 against left-sided colon), the presence of extra-PALN metastasis (HR 6.56), and no use of biologics (HR 3.04).

CONCLUSIONS

This study revealed that hypoalbuminemia as well as RAS mutation, undifferentiated histology, rectal cancer, other site metastasis, and no use of biologics contribute to poor prognosis in CRC patients with PALN metastasis. Nutritional management may be important for improving survival of these patients.

Correlation between circulating tumor DNA and carcinoembryonic antigen levels in patients with metastatic colorectal cancer

Background

Circulating tumor DNA (ctDNA) is a biomarker with potential to reflect comprehensive genomic information and overcome intratumor heterogeneity. In contrast, carcinoembryonic antigen (CEA) is a conventional tumor marker for predicting recurrence, survival, and chemotherapeutic efficacy in patients with metastatic colorectal cancer (mCRC). However, the relationship between them remains unclear. Here, the relationship between plasma ctDNA and CEA levels was evaluated to clarify the advantages and disadvantages of their clinical use.

Methods

A total of 110 patients with mCRC underwent chemotherapy were enrolled. Amplicon‐based plasma genomic profiling of 14 genes that are commonly mutated in CRC by next‐generation sequencing was compared to the CEA level and tumor diameter using Spearman’s correlation coefficient.

Results

The overall concordance rate between the ctDNA and CEA levels was 75.5% (83/110). The correlation coefficient between the ctDNA and CEA levels was lower in the group of patients without liver and lymph node metastases (r = 0.18, p = 0.44) than in the group of patients with liver metastasis (r = 0.48, p < 0.0001). Although the correlation coefficients between tumor diameter and both ctDNA and CEA levels were high in the group of patients with liver metastasis, only the CEA correlation coefficient was maintained in the group of patients without liver and lymph node metastases (r = 0.53, p = 0.01). The characteristics that influenced discordance were liver metastasis and the sum of tumor diameter.

Conclusions

The status of ctDNA and CEA may not be consistent in patients with mCRC without liver metastasis or with a low tumor volume; both results should be considered when deciding a treatment strategy.

Local Treatments in the Unresectable Patient with Colorectal Cancer Metastasis: A Review from the Point of View of the Medical Oncologist

For patients with isolated liver metastases from colorectal cancer who are not candidates for potentially curative resections, non-surgical local treatments may be useful. Non-surgical local treatments are classified according to how the treatment is administered. Local treatments are applied directly on hepatic parenchyma, such as radiofrequency, microwave hyperthermia and cryotherapy. Locoregional therapies are delivered through the hepatic artery, such as chemoinfusion, chemoembolization or selective internal radiation with Yttrium 90 radioembolization. The purpose of this review is to describe the different interventional therapies that are available for these patients in routine clinical practice, the most important clinical trials that have tried to demonstrate the effectiveness of each therapy and recommendations from principal medical oncologic societies.

Upfront primary tumour resection and survival in synchronous metastatic colorectal cancer according to primary tumour location and RAS status: Pooled analysis of the Spanish Cooperative Group for the Treatment of Digestive Tumours (TTD)

INTRODUCTION

Retrospective studies and meta-analyses suggest that upfront primary tumour resection (UPTR) confers a survival benefit in patients with asymptomatic unresectable metastatic colorectal cancer (mCRC) undergoing chemotherapy, however a consensus of its role in routine clinical practice in the current era of targeted therapies is lacking. This retrospective study aimed to analyse the survival benefit of UPTR in terms of tumour location and mutational status, in patients with synchronous mCRC receiving chemotherapy and targeted therapy.

PATIENTS AND METHODS

Survival was analysed in a pooled cohort of synchronous mCRC patients treated with a first-line anti-VEGF or anti-EGFR inhibitor in seven trials of the Spanish TTD group, according to UPTR, tumour-sidedness and mutational profiling.

RESULTS

Of 1334 eligible patients, 642 (48%) had undergone UPTR. UPTR was associated with significantly longer overall survival (OS; 25.0 vs 20.3 months; HR 1.30, 95%CI 1.15-1.48; p < 0.0001). UPTR was associated with significant OS benefit in both left-sided (HR 1.38, 95%CI 1.13-1.69; p = 0.002) and right-sided (HR 1.39, 95%CI 1.00-1.94; p = 0.049) tumours, RASwt (HR 1.29, 95%CI 1.05-1.60; p = 0.016) and BRAFwt (HR 1.49, 95%CI 1.21-1.84; p = 0.0002) tumours, and treatment with anti-EGFRs (HR 1.47, 95%CI 1.13-1.92; p = 0.004) and anti-VEGFs (HR 1.25, 95%CI 1.08-1.44; p = 0.003). Multivariate analysis identified number of metastatic sites, RAS status, primary tumour location and UPTR as independent prognostic factors for OS.

CONCLUSION

Considering the selection bias inherent to this study, our results support UPTR before first-line anti-EGFR or anti-VEGF targeted therapy in right and left-sided asymptomatic unresectable synchronous mCRC patients. RAS/BRAF mutational status may also influence UPTR function.

Taiwan Society of Colon and Rectal Surgeons Consensus on mCRC Treatment

Therapeutic options for metastatic CRC (mCRC) have changed significantly in recent years, greatly increasing the complexity of therapeutic decision-making. Although oncology guidelines have helped improve the care process, guidelines may also limit the flexibility to individualize in-clinic decision-making. This consensus paper addresses specific gaps in the current international guidelines to assist Taiwanese colon and rectal experts make specific therapeutic choices. Over 3 years and three meetings with selected experts on "real-world" Taiwanese practice patterns for mCRC, consensus was achieved. The experts also discussed specific questions during in-depth one-on-one consultation. Outcomes of the discussion were then correlated with published evidence by an independent medical writer. The final consensus includes clinically implementable recommendations to provide guidance in treating Taiwanese mCRC patients. The consensus includes criteria for defining fit and unfit intensive treatment patients, treatment goals, treatment considerations of molecular profiles, treatment consideration, and optimal treatment choices between different patient archetypes, including optimal treatment options based on RAS, BRAF, and microsatellite instability (MSI) status. This consensus paper is the second in the Taiwan Society of Colon and Rectal Surgeons (TSCRS) Consensus series to address unmet gaps in guideline recommendations in lieu of Taiwanese mCRC management. Meticulous discussions with experts, the multidisciplinary nature of the working group, and the final drafting of the consensus by independent medical professionals have contributed to the strong scientific value of this consensus.

Proteasome inhibitors restore the STAT1 pathway and enhance the expression of MHC class I on human colon cancer cells

BACKGROUND

A new strategy, particularly a novel combination, for immunotherapy in microsatellite stable metastatic colorectal cancer (mCRC) treatment needs to be formulated. Studies on the interferon-γ (IFN-γ)/ Janus kinase (JAK)/ signal transducer and activator of transcription (STAT)1 pathway provide new directions in this regard.

METHODS

Our study applies three colon cancer cell lines, including microsatellite stable (MSS) cell lines, which are SW480 and SW620, and microsatellite instability-high (MSI-H) cell line, which is DLD-1. We compared the expressions of immune surface markers on colon cancer cells in response to IFN-γ. We elucidated these mechanisms, which involved the upregulation of immune surface markers. Furthermore, we examined real-world clinical samples using the PerkinElmer Opal multiplex system and NanoString analysis.

RESULTS

We established that the baseline expression of major histocompatibility complex (MHC) class I alleles and programmed death-ligand 1 (PD-L1) were generally low in cell line models. The immune surface markers were significantly increased after IFN-γ stimulation on SW480 but were notably unresponsive on the SW620 cell line. We discovered that STAT1 and phosphorylated STAT1 (pSTAT1) were downregulated in the SW620 cell line. We verified that the STAT1/pSTAT1 could be restored through the application of proteasome inhibitors, especially bortezomib. The expression of MHC class I as downstream signals of STAT1 was also up-regulated by proteasome inhibitors. The similar results were reproduced in DLD-1 cell line, which was also initially unresponsive to IFN-γ. In real-world samples of patients with mCRC, we found that higher STAT1 expression in tumor cells was strongly indicative of a highly immunogenic microenvironment, with significantly higher expression levels of MHC class I and PD-L1, not only on tumor cells but also on non-tumor cells. Furthermore, tumor infiltrating lymphocytes (TILs) were increased in the positive-STAT1 group. Through NanoString analysis, we confirmed that the mRNA expressions of IFN-γ, human leukocyte antigen (HLA)-A, HLA-E, and HLA-G were also significantly higher in the positive-STAT1 group than those in the negative-STAT1 group.

CONCLUSION

Our study provides a novel rationale for the addition of bortezomib, a proteasome inhibitor, into new immunotherapy combinations.

Real-world evidence of the safety and effectiveness of regorafenib in Taiwanese patients with metastatic colorectal cancer: CORRELATE Taiwan

BACKGROUND/PURPOSE

This analysis reports safety and effectiveness data from the Taiwanese cohort of the CORRELATE study.

METHODS

CORRELATE was a prospective, observational study to assess the safety and effectiveness of regorafenib for the treatment of metastatic colorectal cancer (CRC) in real-world clinical practice that was conducted in 13 different countries in Asia, Europe and Latin America. The primary endpoint of the study was incidence of all treatment-emergent AEs (TEAEs), and secondary endpoints included overall survival (OS), progression-free survival (PFS), and disease control rate (DCR).

RESULTS

The global study population (N = 1037) included 128 Taiwanese patients with a median age of 64 years, median weight of 62.02 kg and 66.41% were male. Reduced initiating doses of regorafenib and dose interruptions were common in Taiwanese patients (71.87% and 50.00%, respectively). The safety profile of regorafenib was consistent with that seen in Asian patients in the clinical development trials, including the CORRECT and CONCUR studies, with hand-foot-skin reactions (HFSR) of any grade occurring in 33.59% of patients. Median OS was 11.64 months in the Taiwanese patients (95% confidence interval [CI], 8.36-13.82) and median PFS was 2.17 months (95% CI, 1.97-2.89).

CONCLUSION

The safety and effectiveness of regorafenib in this real-world study was generally consistent with the known efficacy and safety profile in Asian patients in clinical trials.

TRIAL REGISTRATION

NCT02042144.

Second-line chemotherapy after early disease progression during first-line chemotherapy containing bevacizumab for patients with metastatic colorectal cancer

Background

The ML18174 study, which showed benefits of bevacizumab (BEV) continuation beyond progression (BBP) for metastatic colorectal cancer (mCRC), excluded patients with first-line progression-free survival (PFS) shorter than 3 months. The present study was conducted to evaluate the efficacy of second-line chemotherapy after early disease progression during first-line chemotherapy containing bevacizumab.

Methods

The subjects of this study were mCRC patients who experienced disease progression < 100 days from commencement of first-line chemotherapy containing BEV initiated between Apr 2007 and Dec 2016. Second-line chemotherapy regimens were classified into two groups with and without BEV/other anti-angiogenic agents (BBP and non-BBP) and efficacy and safety were compared using univariate and multivariate analysis.

Results

Sixty-one patients were identified as subjects of this study. Baseline characteristics were numerically different between BBP (n = 37) and non-BBP (n = 25) groups, such as performance status (0–1/> 2/unknown: 89/8/3 and 56/40/4%), RAS status (wild/mutant/unknown: 32/54/16 and 76/16/8%). Response rate was 8.6% in BBP group and 9.1% in non-BBP group (p = 1.00). Median PFS was 3.9 months in BBP group and 2.8 months in non-BBP group (HR [95%CI]: 0.79 [0.46–1.34], p = 0.373, adjusted HR: 0.87 [0.41–1.82], p = 0.707). Median overall survival was 8.5 months in BBP group and 5.4 months in non-BBP group (HR 0.66 [0.38–1.12], p = 0.125, adjusted HR 0.53 [0.27–1.07], p = 0.078).

Conclusion

In mCRC patients who experienced early progression in first-line chemotherapy, second-line chemotherapy showed poor clinical outcomes regardless use of anti-angiogenic agents.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08890-6.

Real-world outcomes of regorafenib combined with immune checkpoint inhibitors in patients with advanced or metastatic microsatellite stable colorectal cancer: A multicenter study

Background

Treatment strategies are limited for patients with chemotherapy refractory microsatellite stable (MSS) colorectal cancer. We aim to evaluate the efficacy and safety of immune checkpoint inhibitors (ICIs) combined with regorafenib in this population in routine clinical practice.

Methods

We retrospectively analyzed patients with advanced or metastatic colorectal cancer who received at least one dose of ICIs combined with regorafenib in 14 Chinese medical centers. The primary outcome was objective response rate (ORR). This study was registered at ClinicalTrials.gov on February 2020 (NCT04771715).

Results

Eighty-four patients received ICIs combined with regorafenib from January 2019 to January 2021. Most patients (91%) received two or more systemic treatment lines before the study treatment. Seventy-six patients (90%) had confirmed MSS status. At a median follow-up of 5.5 months, four patients achieved partial response (5%) and 37 patients achieved stable disease (45%) as the best response. The median progression-free survival (PFS) was 3.1 months, and the median overall survival was 17.3 months. Eleven patients (13%) remained progression-free for more than 6 months. Baseline liver metastasis (HR 1.98, 95%CI 1.07–3.69, P = 0.03) and neutrophil–lymphocyte ratio (NLR) of ≥ 1.5 (HR 2.83, 95%CI 1.00–7.98, P = 0.05) were associated with shorter PFS in multivariate analysis. Grade 3 or higher treatment-related adverse events (TRAEs) occurred in 16 patients (19%).

Conclusion

The combination of ICIs with regorafenib can be a valuable treatment option for a proportion of patients with chemotherapy refractory MSS colorectal cancer. Patients with no liver metastasis and a low NLR at baseline may derive most benefit from this strategy.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00262-021-03083-3.

Construction of a New Tumor Immunity-Related Signature to Assess and Classify the Prognostic Risk of Colorectal Cancer

Purpose

Although immunotherapy and checkpoint inhibitors contribute to the treatment of colorectal cancer (CRC), few patients can benefit from these treatments. Therefore, our goal was to develop a marker based on immune-related genes to predict the prognosis of patients with CRC to guide treatment strategies.

Methods

Gene expression data from colorectal cancer patients in the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas were analyzed systematically. We used Cox regression to identify immune-related genes with potential prognostic value. The expression of immune genes, infiltration level of immune cells, and several immune-related molecules were further compared between the high-risk and low-risk groups. Gene Ontology analysis and Kyoto Encyclopedia of Genes and Genomes pathway analyses were used for functional analysis.

Results

Five GEO datasets were integrated into a merged GEO dataset, which showed obvious survival in StromalScore and ESTIMATEScore. WGCNA showed that 749 genes of the pink module are related to immunity, 95 of which are related to prognosis, correlating with cytokine–cytokine receptor interaction and natural killer cell-mediated cytotoxicity. Among these genes, an 11-gene signature was developed through stability selection and LASSO Cox regression. Univariate and multifactorial Cox regression analyses demonstrated that gene signature was an independent prognostic factor for predicting survival in patients with colorectal cancer. Samples from the low-risk group may be more sensitive to immunotherapy. In addition, the nomogram risk prediction model effectively predicted the prognosis of CRC patients by appropriately stratifying the risk scores.

Conclusion

In conclusion, we developed a novel immune-related gene signature that may be useful in predicting cancer progression and prognosis, thus contributing to the individualized management of colorectal cancer patients.

Development and Validation of a Novel Serum Prognostic Marker for Patients with Metastatic Colorectal Cancer on Regorafenib Treatment

Simple Summary

Regorafenib has proven its efficacy for later-line treatment of mCRC. However, treatment often brings substantial toxicities that lead clinicians to assess the risk-to-benefit ratio in heavily pretreated patients. Thus, it is crucial to develop a prognostic factor and model for guiding patient selection. In this study, we represent a new serum biomarker to serve as an independent prognostic factor for patients receiving regorafenib. All 4 factors of the prognostic model were employed with an excellent discriminatory ability. This result should be validated in further confirmatory studies.

Abstract

(1) Background: To investigate the prognostic value of cancer-inflammation prognostic index (CIPI) in patients with metastatic colorectal cancer (mCRC) on regorafenib treatment; (2) Methods: Patients with mCRC who were given regorafenib as later-line treatment at Kaohsiung and Linkou Chang-Gung Memorial Hospital between November 2014 and January 2021 were consecutively enrolled. All relevant clinicopathologic, laboratory data and survival status were recorded. Independent prognostic factors were determined by the multivariate Cox regression method; (3) Results: In total, 106 patients in the training cohort and 250 in the validation cohort were enrolled. The median OS for patients with CIPI ≥ 300 and < 300 in the training cohort was 3.8 and 9.0 months, respectively (hazard ratio (HR) 2.78, 95% confidence interval (CI) 1.82–4.23; p < 0.0001). Time to regorafenib, liver metastasis and CIPI were independent factors by multivariate Cox regression analyses. A new scoring model demonstrated a good discriminatory ability to risk stratification of a patient’s survival; (4) Conclusions: We identified CIPI as a novel serum marker highly associated with overall survival in patients with mCRC receiving regorafenib treatment. Further confirmatory studies are warranted.

Clinical and Molecular Features in Patients Undergoing Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Peritoneal Carcinosis from Colorectal Cancer

PURPOSE

Careful patient selection plays a crucial role in avoiding overtreatment and further increases survival rates in patients undergoing cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) for colorectal cancer (CRC) with peritoneal metastases (PM).

METHODS

The clinical and molecular factors influencing survival in patients who had undergone CRS with HIPEC between January 2015 and December 2018 were analyzed.

RESULTS

Sixty-six patients underwent CRS with HIPEC during the study period. The median overall survival (OS) was 36 months, with a 3-year OS of 43%. Multivariate analysis revealed increased PCI (HR: 1.21; 95% CI: 1.02-1.41; p = 0.020), right-sided primary tumor (HR: 3.01; 95% CI: 1.27-7.13; p = 0.017), and BRAF V600E mutation (HR: 4.55; 95% CI: 1.21-17.21; p = 0.025) as independent predictors for worse OS.

CONCLUSION

In addition to confirming the prognostic role of PCI, our study extends the role of BRAF mutation and right primary tumor location as markers for worse prognosis.

Role of salt‑inducible kinase 2 in the malignant behavior and glycolysis of colorectal cancer cells

Colorectal cancer (CRC) is the third most common type of cancer worldwide. Currently, surgery, chemotherapy and radiation therapy are the conventional approaches used to treat CRC. However, these therapy strategies cause several side effects. The present study aimed to develop an alternative and more effective treatment approach for patients with CRC. It has been reported that salt-inducible kinase 2 (SIK2) acts as an oncogene. Therefore, in the present study, the expression levels of SIK2 were determined in CRC cells using western blot analysis and reverse transcription-quantitative PCR. In addition, SIK2 was knocked down in CRC cells to evaluate its role in cell proliferation, migration, invasion and glycolysis using Cell Counting Kit-8, wound healing, Transwell assays and glycolysis cell-based assay kit, respectively. Additionally, the target genes of SIK2 were identified using bioinformatics analysis, while SIK2 overexpression experiments were carried out to determine whether SIK2 could regulate CRC cell malignant behavior and glycolysis. The results revealed that SIK2 was upregulated in CRC cells. Furthermore, SIK2 knockdown attenuated CRC cell proliferation, migration, invasion and glycolysis. Bioinformatics analysis predicted that SIK2 could interact with tripartite motif containing 28 (TRIM28), while TRIM28 overexpression could reverse the effects of SIK2 silencing on cell proliferation, migration, invasion and glycolysis. This finding indicated that the aforementioned effects of SIK2 were mediated by regulating TRIM28. In conclusion, the findings of the present study suggested that SIK2 may be involved in CRC carcinogenesis and glycolysis by regulating TRIM28 expression. These findings could provide a novel approach to targeted therapy and clinical diagnosis of CRC in the future.

Transgelin-2 interacts with CD44 to regulate Notch1 signaling pathway and participates in colorectal cancer proliferation and migration

The abnormal expression of transgelin-2 (TAGLN2) is related to tumor occurrence and progression. However, the underlying molecular mechanism of TAGLN2 in human colorectal cancer (CRC) is still poorly understood. Compared with adjacent tissues, TAGLN2 is overexpressed in CRC tissues. Its expression level is negatively correlated with the overall survival rate of patients with CRC. In addition, knockdown of TAGLN2 inhibited the proliferation and invasion of CRC cells. We also showed that TAGLN2 could interact with CD44 to regulate the Notch-1 signaling pathway. Our findings indicate there is increased TAGLN2 expression in CRC and that it may serve as a promising potential therapeutic target for CRC.

Low-Dose Apatinib Combined With S-1 in Refractory Metastatic Colorectal Cancer: A Phase 2, Multicenter, Single-Arm, Prospective Study

Purpose

Apatinib is an approved third-line treatment for metastatic gastric cancer in China and demonstrates good safety, tolerability, and efficacy in other advanced solid tumors. The aim of this prospective, single-arm, multicenter, phase 2 study was to assess the efficacy and safety of low-dose apatinib combined with S-1 in the treatment of refractory mCRC.

Patients and Methods

Patients with refractory mCRC were enrolled and administered apatinib combined with S-1 until disease progression, patient decision to withdraw, or unacceptable toxic effects. The primary endpoint was investigator-evaluated progression-free survival (PFS) and the secondary endpoints were overall survival (OS), objective response rate (ORR), disease control rate (DCR).

Results

From December 2017 to December 2018, 30 patients were enrolled and 29 patients were eligible for the evaluation of efficacy and safety. The median PFS (mPFS) and OS (mOS) were 7.9 and 12.9 months, respectively. Exploratory analysis revealed that patients administered S-1 ≥ 70 days achieved longer mPFS and mOS. Four patients achieved a partial response, 22 achieved stable disease, and three had progressive disease, attributing to an ORR of 13.79% and a DCR of 89.66%. Ten grade 3 adverse events were reported and the frequency of each grade 3 adverse event was less than 5%. No grade 4 side events were observed.

Conclusions

These results indicated that apatinib combined with S-1 showed promising efficacy and manageable toxicity in patients with progressive mCRC after at least 2 prior lines of therapy, making it a promising therapeutic option for mCRC treatment.

Clinical Trial Registration

https://clinicaltrials.gov/ct2/show/NCT03397199, identifier NCT03397199.

SCRUM-Japan GI-SCREEN and MONSTAR-SCREEN: Path to the realization of biomarker-guided precision oncology in advanced solid tumors

Comprehensive genomic profiling enables the detection of genomic biomarkers in advanced solid tumors. However, efficient patient screening for the success of precision oncology remains challenging due to substantial barriers, such as genotyping costs and accessibility to matched therapies. To address these challenges, we launched GI‐SCREEN, a nationwide gastrointestinal cancer genomic screening project within the SCRUM‐Japan network in 2015 with the specific purpose of matching patients with a diverse portfolio of affiliated interventional targeted therapy trials. Subsequently, we initiated the molecular profiling projects GOZILA, MONSTAR‐SCREEN‐1, and MONSTAR‐SCREEN‐2, which incorporate tissue and plasma multiomics approaches to accurately identify patients with advanced solid tumors who would benefit from matched therapies. These projects have led to a significant increase in patient participation in targeted clinical trials and the approval of several therapeutics and companion diagnostics. Additionally, clinicogenomic analyses utilizing the SCRUM‐Japan database have provided new insights into the molecular mechanisms of advanced solid tumors. In this review, we describe the path to the realization of cancer precision medicine for patients with advanced solid tumors based on the SCRUM‐Japan GI‐SCREEN and MONSTAR‐SCREEN platforms.

Quality Standards for Surgery of Colorectal Peritoneal Metastasis After Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy

BACKGROUND

The standardization of surgical outcomes throughout surgical procedures is mandatory. Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS + HIPEC) should provide proficient oncological and surgical outcomes.

STUDY DESIGN

The aim of this study was to identify clinically relevant quality indicators and their quality standard, and to determine their acceptable quality limit. A systematic review on cytoreductive results from 2000 to 2018 was performed focusing on clinical guidelines, consensus conferences, and publications. After the selection of quality indicators, a systematic review of indexed references was performed in order to calculate the quality standard for each indicator.

STUDY SELECTION

Unicentric/multicentric series, comparative studies, and clinical trials. Studies were to include outcomes after cytoreduction of colorectal origin and series with more than 50 patients. Quality indicators with at least 10 series were mandatory and objective measurements were also mandatory for inclusion.

MAIN OUTCOME MEASUREMENTS

Quality indicators selected were 1- to 5-year survival, overall disease-free survival, 1- to 5-year disease-free survival, complete surgical resection, duration of surgery, length of stay, overall morbimortality, major morbidity, re-intervention, postoperative hemorrhage, intestinal fistula, anastomotic leakage, wound infection, postoperative medical complications, overall recurrence, and failure to rescue.

RESULTS

The most relevant quality indicators and critical quality limits were overall disease-free survival and 5-year overall disease-free survival (14 months and <10 months, and 14% and <4%, respectively), completeness of surgical resection (89% and <80%, respectively), overall mortality (3% and >8%, respectively), overall morbidity (47% and >63%, respectively), failure to rescue (12% and <30%, respectively), reintervention (13 and <22%, respectively), anastomotic leakage (6% and <13%, respectively), and overall recurrence (60% and <74%, respectively).

CONCLUSION

This is the first study to assess quality standards in CRS + HIPEC for colorectal peritoneal metastases. The current data are of particular relevance for future studies to control the variability of this surgery.

Randomized phase II study of SOX+B-mab versus SOX+C-mab in patients with previously untreated recurrent advanced colorectal cancer with wild-type KRAS (MCSGO-1107 study)

Background

Although chemotherapy for metastatic colorectal cancer (mCRC) has improved, the standard chemotherapy regimens for patients with RAS wild-type mCRC remain debated. This study aimed to compare S-1 and oxaliplatin (SOX) + bevacizumab (B-mab) with SOX + cetuximab (C-mab) in patients with previously untreated recurrent advanced CRC with wild-type KRAS.

Methods

This randomized phase II, open-label, multicenter study compared the efficacy and safety of SOX+B-mab with SOX+C-mab in patients with previously untreated advanced CRC with wild-type KRAS. Between February 2012 and October 2016, 45 patients were enrolled.

Results

Overall response rates were 59.1 and 43.5% (p = 0.29) and disease control rates were 90.9 and 91.3% (p = 0.96) in the SOX+B-mab and SOX+C-mab groups, respectively. Median overall survival (OS) was 25.3 and 15.5 months (HR = 0.607, p = 0.167) and median progression-free survival (PFS) were 11.7 and 5.5 months (HR = 0.558, p = 0.077) in the SOX+B-mab and SOX+C-mab groups, respectively. The OS and PFS of patients with early tumor shrinkage (ETS) were not significantly different in the SOX+B-mab group. However, they were significantly better when ETS was ≥20 in the SOX+C-mab group (p = 0.032 and p = 0.003, respectively).

Conclusions

The efficacy and safety of SOX+B-mab and SOX+C-mab for wild-type KRAS recurrent advanced CRC as first-line chemotherapy were almost the same. Consideration of the treatment strategy based on ETS may improve patient prognosis, especially in patients receiving the SOX+C-mab regimen.

Trial registration

UMIN Clinical Trials Registry (UMIN000006706).

Date of registration: NOV/11/2011.

URL of trial registry record:

https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000007920

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08690-y.

Percutaneous radiofrequency ablation near large vessels in beagle livers: the impact of time and distance on the ablation zone

PURPOSE

To investigate the effects of ablation time and distance between the radiofrequency ablation (RFA) electrode tip and a large vessel on the ablation zone in beagle livers.

METHODS

Sixty-one percutaneous RFA coagulation zones were created near large vessels in 10 beagle livers in vivo. The ablated lesions were divided into four groups based on ablation time and distance between the electrode tip and a large vessel (group A, 3 min 0.5 cm; group B, 3 min 0 cm; group C, 5 min 0.5 cm; group D, 5 min 0 cm). The ablated area, long-axis diameters, short-axis diameters, and vessel wall injury were examined.

RESULTS

With a fixed ablation time, the ablation zone created with the electrode tip at 0.5 cm from the large vessel was significantly larger than at 0 cm (p < .05). At a fixed distance between the electrode tip and vessel, the ablation zone created for 5 min was significantly larger than for 3 min (p < .05). The frequency of vessel wall injury in the 0 cm groups was significantly higher than that in the 0.5 cm groups (37.5% vs. 6.9%; p = .003, odds ratio, 7.43). The ratio of width to depth (Dw/Dz) was larger in the 0.5 cm groups than in the 0 cm groups (p < .001).

CONCLUSION

The ablation zone increased with longer ablation times and greater distances between the RFA tip and large vessels for perivascular lesions. The distance between the needle tip and blood vessels is an important factor that affects the overall ablation outcome.

Cross-platform comparison of next-generation sequencing and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry for detecting KRAS/NRAS/BRAF/PIK3CA mutations in cfDNA from metastatic colorectal cancer patients

Background

Examining tumor KRAS/NRAS/BRAF/PIK3CA status in metastatic colorectal cancer (mCRC) is essential for treatment selection and prognosis evaluation. Cell‐free DNA (cfDNA) in plasma is a feasible source for tumor gene analysis.

Methods

In this study, we recruited mCRC patients and analyzed their KRAS/NRAS/BRAF/PIK3CA status in cfDNA using two platforms, next‐generation sequencing (NGS) and matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF). The performance between the two platforms and the concordance rate between cfDNA and tissue were analyzed. The relationship between cfDNA‐related variables and clinical variables was also assessed. Tumor mutations in cfDNA from patients receiving continuous treatments were monitored in the follow‐ups.

Results

Next‐generation sequencing and MALDI‐TOF had similar specificity (100.0% vs. 99.3%) and negative predictive value (99.9% vs. 99.4%), whereas NGS had higher sensitivity (97.1% vs. 85.3% of MALDI‐TOF) and positive predictive value (100% vs. 82.9% of MALDI‐TOF). The overall concordance rate of NGS and MALDI‐TOF was 98.6%. For the reportable types of mutations in both cfDNA and tissue, the concordance rate was 96.1%. Among 28 tissue‐positive patients, the allele frequencies of tumor mutations in cfDNA were higher in patients with primary tumor burden (p = 0.0141). Both CEA and CA 19‐9 were positively correlated with cfDNA concentration (r = 0.3278 and r = 0.3992). The allele frequencies of tumor mutations changed with disease progression.

Conclusions

Next‐generation sequencing showed slightly better performance in detecting cfDNA mutations and was more suitable for clinical practice. cfDNA‐related variables reflected the tumor status and showed a promising potential in monitoring disease progression.

The efficacy and safety of bevacizumab combined with FOLFOX regimen in the treatment of advanced colorectal cancer: A systematic review and meta-analysis

BACKGROUND

It is necessary to systematically evaluate the clinical efficacy and safety of bevacizumab (BEV) combined with 5-fluorouracil + leucovorin + oxaliplatin (FOLFOX) regimen in the treatment of advanced colorectal cancer.

METHODS

We searched the PubMed et al databases for randomized controlled trials (RCTs) on the BEV combined with the FOLFOX regimen in the treatment of advanced colorectal cancer up to January 20, 2021. The Cochrane Collaborations' risk of bias tool was used for the quality assessment of included RCTs. Revman5.3 software was used for meta-analysis.

RESULTS

Eleven RCTs with a total of 3178 patients with advanced colorectal cancer were included, meta-analysis results showed that the objective response rate (odds ratio [OR] = 3.15, 95% confidence intervals [CI]: 2.25-4.40, P < .001) and cancer control rate (OR = 2.73, 95% CI: 1.91-3.90, P < .001) of BEV + FOLFOX were higher than that of FOLFOX group. And the incidence of gastrointestinal adverse reactions (OR = 1.29, 95% CI: 1.07-1.55, P = .008) in the BEV + FOLFOX group was higher than that of the FOLFOX group, there were no significant differences in the incidence of leukopenia (OR = 1.04, 95% CI: 0.72-1.50, P = .83), hypertension (OR = 3.92, 95% CI: 0.81-18.88, P = .09) and neurotoxicity (OR = 1.00, 95% CI: 0.8-1.27, P = .98) between the 2 groups.

CONCLUSION

BEV combined with the FOLFOX regimen is more effective than the FOLFOX regimen alone in the treatment of advanced colorectal cancer, but it may also increase the risk of gastrointestinal adverse reactions.

Treatment of Patients With Late-Stage Colorectal Cancer: ASCO Resource-Stratified Guideline

PURPOSE

To provide expert guidance to clinicians and policymakers in resource-constrained settings on the management of patients with late-stage colorectal cancer.

METHODS

ASCO convened a multidisciplinary, multinational Expert Panel that reviewed existing guidelines, conducted a modified ADAPTE process, and used a formal consensus process with additional experts for two rounds of formal ratings.

RESULTS

Existing sets of guidelines from four guideline developers were identified and reviewed; adapted recommendations from five guidelines form the evidence base and provided evidence to inform the formal consensus process, which resulted in agreement of ≥ 75% on all recommendations.

RECOMMENDATIONS

Common elements of symptom management include addressing clinically acute situations. Diagnosis should involve the primary tumor and, in some cases, endoscopy, and staging should involve digital rectal exam and/or imaging, depending on resources available. Most patients receive treatment with chemotherapy, where chemotherapy is available. If, after a period of chemotherapy, patients become candidates for surgical resection with curative intent of both primary tumor and liver or lung metastatic lesions on the basis of evaluation in multidisciplinary tumor boards, the guidelines recommend patients undergo surgery in centers of expertise if possible. On-treatment surveillance includes a combination of taking medical history, performing physical examinations, blood work, and imaging; specifics, including frequency, depend on resource-based setting.

Additional information is available at www.asco.org/resource-stratified-guidelines.

Combination therapy of bevacizumab with either S-1 and irinotecan or mFOLFOX6/CapeOX as first-line treatment of metastatic colorectal cancer (TRICOLORE): Exploratory analysis of RAS status and primary tumour location in a randomised, open-label, phase III, non-inferiority trial

AIM

The TRICOLORE trial previously demonstrated that S-1 and irinotecan plus bevacizumab was non-inferior, based on progression-free survival (PFS), to 5-fluorouracil, leucovorin and oxaliplatin (mFOLFOX6)/capecitabine and oxaliplatin (CapeOX) plus bevacizumab as first-line chemotherapy for metastatic colorectal cancer (mCRC). Overall survival (OS) data were immature at the time of the primary analysis.

METHODS

In total, 487 patients from 53 institutions with previously untreated mCRC were randomly assigned (1:1) to receive either mFOLFOX6/CapeOX plus bevacizumab (control group) or S-1 and irinotecan plus bevacizumab (experimental group; 3- or 4-week regimen). The final OS data were analysed from follow-up data collected until 30th September 2017.

RESULTS

With a median follow-up period of 48.7 months, median survival times were 32.6 and 34.3 months (hazard ratio [HR]: 0.89, 95% confidence interval [CI]: 0.72-1.10, P = 0.293) and median PFS durations were 10.8 and 14.0 months in the control and experimental groups, respectively (HR: 0.86, 95% CI: 0.71-1.04, P < 0.0001 for non-inferiority). In patients with left-sided RAS wild-type tumours, median PFS durations were 11.4 and 16.9 months in the control and experimental groups, respectively (HR: 0.68, 95% CI: 0.48-0.96, P = 0.028).

CONCLUSION

S-1 and irinotecan plus bevacizumab resulted in comparable OS and non-inferior PFS with that of mFOLFOX6/CapeOX plus bevacizumab treatment as first-line chemotherapy for patients with mCRC. We recommend the use of S-1 and irinotecan plus bevacizumab as a standard first-line regimen independent of tumour sidedness or RAS status in mCRC.

TRIAL REGISTRATION

UMIN-CTR: 000007834.

Prognostic Value of Combined Preoperative Carcinoembryonic Antigen and Prognostic Nutritional Index in Patients With Stage II-III Colon Cancer

Background: Tumor status can affect patient prognosis. Prognostic nutritional index (PNI), as a nutritional indicator, is closely related to the prognosis of cancer. However, few studies have examined the combined prognostic value of CEA and PNI in patients. This study investigated the relationship between CEA/PNI and prognosis of colon cancer patients.

Methods: A total of 513 patients with stage II–III colon cancer who underwent curative resection at two medical centers from 2009 to 2019 were included. Clinicopathological factors were assessed and overall survival (OS) was assessed in a cohort of 413 patients. Multivariate analysis was used to identify independent prognostic variables to construct histograms predicting 1-year and 3-year OS. Data from 100 independent patients in the validation group was used to validate the prognostic model.

Results: The median OS time was 33.6 months, and mortality was observed in 54 patients. Multivariate analysis revealed that preoperative CEA/PNI, lymph node metastasis, peripheral nerve invasion, operation mode, and postoperative chemotherapy were independent factors for prognosis evaluation and thus were utilized to develop the nomogram. The C-index was 0.788 in the learning set and 0.836 in the validation set. The calibration curves reached favorable consensus among the 1-, 3-year OS prediction and actual observation.

Conclusion: The combined use of CEA and PNI is an independent prognostic factor and thus can serve as a basis for a model to predict the prognosis of patients with stage II–III colon cancer.

Current therapy of advanced colorectal cancer according to RAS/RAF mutational status

Colorectal cancer is a clinically and molecularly heterogeneous disease. Currently, extended RAS and BRAF mutation testing is obligatory in routine clinical practice before starting any treatment in the metastatic setting. Treatment decision making also includes assessment of the clinical condition of the patient, definition of the treatment goal, and consideration of the primary tumor site. Biological treatment is part of the first-line drug combination unless contraindicated. Mutational status is significantly associated with the outcome of patients and is strongly predictive for anti-EGFR-targeted therapy. The prognosis of RAS mutant CRC is clearly inferior to wild-type cases. RAS remains an elusive target, and specific treatment options are not yet available. Recently, promising results of a direct KRAS G12C inhibitor have been reported; however, further confirmation is needed. The biomarker landscape in mCRC is evolving; new promising markers are awaited with the chance of more precise targeted treatment.

Prognostic role and biologic features of Musashi-2 expression in colon polyps and during colorectal cancer progression

BACKGROUND

The RNA-binding protein Musashi-2 (MSI2) controls the translation of proteins that support stem cell identity and lineage determination and is associated with progression in some cancers. We assessed MSI2 as potential clinical biomarker in colorectal cancer (CRC) and tubulovillous adenoma (TA) of colon mucosa.

METHODS

We assessed 125 patients, of whom 20 had polyps of the colon (TAs), and 105 had CRC. Among 105 patients with CRC, 45 had stages I-III; among metastatic CRC (mCRC) patients, 31 had synchronous and 29 metachronous liver metastases. We used immunohistochemistry to measure MSI2 expression in matching specimens of normal tissue versus TAs, primary CRC tumors, and metastases, correlating expression to clinical outcomes. We analyzed the biological effects of depleting MSI2 expression in human CRC cells.

RESULTS

MSI2 expression was significantly elevated in polyps versus primary tissue, and further significantly elevated in primary tumors and metastases. MSI2 expression correlated with decreased progression free survival (PFS) and overall survival (OS), higher tumor grade, and right-side localization (p = 0.004) of tumors. In metastases, high MSI2 expression correlated with E-cadherin expression. Knockdown of MSI2 in CRC cells suppressed proliferation, survival and clonogenic capacity, and decreased expression of TGFβ1, E-cadherin, and ZO1.

CONCLUSION

Elevated expression of MSI2 is associated with pre-cancerous TAs in the colonic mucosa, suggesting it is an early event in transformation. MSI2 expression is further elevated during CRC progression, and associated with poor prognosis. Depletion of MSI2 reduces CRC cell growth. These data imply a causative role of MSI2 overexpression at multiple stages of CRC formation and progression.

Safety and efficacy of panitumumab in combination with trifluridine/tipiracil for pre-treated patients with unresectable, metastatic colorectal cancer with wild-type RAS: The phase 1/2 APOLLON study

BACKGROUND

We aimed to assess the safety and efficacy of combination treatment with panitumumab plus trifluridine/tipiracil (FTD/TPI) in patients with wild-type RAS metastatic colorectal cancer (mCRC) who were refractory/intolerant to standard therapies other than anti-epidermal growth factor receptor therapy.

METHODS

APOLLON was an open-label, multicentre, phase 1/2 trial. In the phase 1 part, 3 + 3 de-escalation design was used to investigate the recommended phase 2 dose (RP2D); all patients in the phase 2 part received the RP2D. The primary endpoint was investigator-assessed progression-free survival (PFS) rate at 6 months. Secondary endpoints included PFS, overall survival (OS), overall response rate (ORR), disease control rate (DCR), time to treatment failure (TTF), and safety.

RESULTS

Fifty-six patients were enrolled (phase 1, n = 7; phase 2, n = 49) at 25 Japanese centres. No dose-limiting toxicities were observed in patients receiving panitumumab (6 mg/kg every 2 weeks) plus FTD/TPI (35 mg/m2 twice daily; days 1-5 and 8-12 in a 28-day cycle), which became RP2D. PFS rate at 6 months was 33.3% (90% confidence interval [CI] 22.8-45.3). Median PFS, OS, ORR, DCR, and TTF were 5.8 months (95% CI 4.5-6.5), 14.1 months (95% CI 12.2-19.3), 37.0% (95% CI 24.3-51.3), 81.5% (95% CI 68.6-90.8), and 5.8 months (95% CI 4.29-6.21), respectively. Neutrophil count decreased (47.3%) was the most common Grade 3/4 treatment-emergent adverse event. No treatment-related deaths occurred.

CONCLUSION

Panitumumab plus FTD/TPI exhibited favourable anti-tumour activity with a manageable safety profile and may be a therapeutic option for pre-treated mCRC patients.

Single-institute comparison of the efficacy of systemic chemotherapy for oesophagogastric junction adenocarcinoma and stomach adenocarscinoma in a metastatic setting

BACKGROUND

Different approaches are used to treat resectable tumours in patients having adenocarcinoma at the oesophagogastrointestinal junction (EGJ) or in the stomach. However, there is limited information about treatment efficacy for patients at metastatic stage. A recent molecular analysis of upper gastrointestinal tract adenocarcinoma revealed that the anatomical location can influence the molecular backgrounds of tumours. This study sought to elucidate whether different therapeutic approaches should be used for EGJ tumours relative to those in the stomach.

METHODS

This retrospective cohort study was conducted at a single institute in Japan. Patients having metastatic or recurrent adenocarcinoma in the EGJ or stomach who underwent platinum doublet chemotherapy between January 2007 and August 2014 were enrolled. Patients in the EGJ tumour group had tumours having an epicentre within 2 cm proximal or 5 cm distal to the estimated anatomical EGJ and cardia.

RESULTS

Among 378 consecutively enrolled patients, 61 were grouped into the EGJ group and the remainder comprised the stomach group. The EGJ group had more men and lower incidence of diffuse type and Borrmann type IV tumours and peritoneum metastasis compared with the stomach group. The median overall survival of patients in the EGJ and stomach groups was similar (17.3 months (95% CI 13.5 to 23.2) vs 14.5 months (95% CI 13.3 to 16.4)). No statistically significant difference was observed in progression-free survival. Although the overall postprogression survival differed significantly between the EGJ and stomach groups (8.2 months (95% CI 5.7 to 12.7) vs 7.1 months (95% CI 6.1 to 7.8)), on grouping patients by histological type, the two groups exhibited similar postprogression survival. Multivariate analysis demonstrated that diffuse-type histology, higher serum CA19-9 levels and neutrophil to lymphocyte ratios were independent poor prognostic factors.

CONCLUSIONS

Different clinicopathological features of EGJ adenocarcinoma were not associated with clinical outcomes of platinum doublet chemotherapy. Histological subtype rather than anatomical location has more significance for treatment decisions for advanced gastric cancers.

Insulin-Like Growth Factor 2 mRNA-Binding Protein 1 (IGF2BP1) Is a Prognostic Biomarker and Associated with Chemotherapy Responsiveness in Colorectal Cancer

Insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) is an RNA-binding protein and serves as a post-transcriptional fine-tuner regulating the expression of mRNA targets. However, the clinicopathological roles of IGF2BP1 in colorectal cancer (CRC) remains limited. Thus, we aimed to elucidate the clinical significance and biomarker potentials of IGF2BP1 in CRC. A total of 266 specimens from two sets of CRC patients were collected. IGF2BP1 expression was studied by immunohistochemical (IHC) staining. The Kaplan-Meier survival plot and a log-rank test were used for survival analysis. The Cox proportional hazards model was applied to determine the survival impact of IGF2BP1. Public datasets sets from The Cancer Genome Atlas (TCGA) and Human Cancer Metastasis Database (HCMDB), receiver operating characteristic (ROC) plotter, and two CRC cell lines, HCT-116 and DLD-1, were used for validating our findings. We showed that IGF2BP1 was overexpressed in tumor specimens compared to 13 paired normal parts by examining the immunoreactivity of IGF2BP1 (p = 0.045). The increased expression of IGF2BP1 in primary tumor parts was observed regardless of metastatic status (p < 0.001) in HCMDB analysis. IGF2BP1 expression was significantly associated with young age (59.6% vs. 46.7%, p-value = 0.043) and advanced stage (61.3% vs. 40.0%, p-value = 0.001). After controlling for confounding factors, IGF2BP1 remained an independent prognostic factor (HR = 1.705, p-value = 0.005). TCGA datasets analysis indicated that high IGF2BP1 expression showed a lower 5-year survival rate (58% vs. 65%) in CRC patients. The increased expression of IGF2BP1 in chemotherapy non-responder rectal cancer patients was observed using a ROC plotter. Overexpression of IGF2BP1 promoted the colony-forming capacity and 5-fluorouracil and etoposide resistance in CRC cells. Here, IGF2BP1 was an independent poor prognostic marker in CRC patients and contributed to aggressive phenotypes in CRC cell lines.

Largely varying patterns and trends of primary cancer-directed resection for gastric carcinoma with synchronous distant metastasis in Europe and the US: a population-based study calling for further standardization of care

Aims:

The role of resection remains debated in cases of metastatic gastric carcinoma (mGC). Some mGCs are technically resectable. At the population level, the real-world application of resection for mGC remains largely unclear in most Western countries. This large, population-based international investigation aimed to reveal the resection patterns and trends for mGC and the treatment-associated factors in Europe and the US.

Methods:

Data on cases with microscopically-confirmed primary invasive stomach carcinoma with distant metastasis were obtained from the nationwide cancer registries of the Netherlands, Belgium, Norway, Sweden, Estonia, and Slovenia and the US Surveillance, Epidemiology, and End Results-18 database. We calculated age-standardized rates of primary cancer-directed resection and assessed resection trends using linear regression. We investigated associations of treatment with patient and cancer factors using multivariable-adjusted log-binomial regression.

Results:

Among 133,321 patients with gastric cancer, overall, 40,215 cases with mGC diagnosed between 2003–2017 were investigated. Age-standardized resection rates significantly declined over time in the US, Belgium, Sweden, and Norway (by 5–14%). Resection rates greatly differed from 5% to 16% in 2013–2014. Cases with older ages, cardia tumors, or tumors involving adjacent structures were significantly less often operated across most countries. Sex was not significantly associated with resection. Across countries the association patterns and strengths differed largely. With multivariable adjustment, resection rates decreased significantly in all countries except Slovenia and Estonia (prevalence ratio per year = 0.90–0.98), and the decreasing trends were consistently observed in various stratifications by age and location.

Conclusion:

In Europe and the US, resection patterns and trends largely varied across countries for mGCs, which were mostly less often resected in the early 21st century. Various resection-associated factors were shown, with greatly varying association patterns and strengths. Our report could aid to identify discrepancies in clinical practice and highlight the great need for further clarifying the role of resection in mGCs to enhance standardization of care.

NeoRAS wild-type in metastatic colorectal cancer: Myth or truth?-Case series and review of the literature

Upfront KRAS and NRAS gene testing ('RAS') is the standard of care for metastatic colorectal cancer (mCRC), to guide first-line treatment. The presence of RAS mutation (MT) is a negative predictor for the efficacy of anti-EGFR antibodies and the use of cetuximab and panitumumab is restricted to RAS wild-type (WT) mCRC. Conversion from RAS WT to RAS MT mCRC after treatment with anti-EGFR antibodies is a known and well-described acquired resistance mechanism. The by far less frequent 'NeoRAS wild-type' phenomenon (reversion from RAS MT to RAS WT) has recently drawn attention. The proposed effect of chemotherapy on RAS status in mCRC patients is not fully understood. Because of the intriguing biological consequence of a RAS MT to RAS WT reversion, subsequent treatment of NeoRAS WT patients with anti-EGFR antibodies is increasingly being discussed. Here, we report three clinical cases of NeoRAS WT mCRC patients, which received standard-of-care regimens for RAS MT mCRC. Anti-EGFR antibodies were used in two out of three patients after progression of the disease. One of the patients had a long-term response. In line with our observations, NeoRAS WT phenomenon occurs in clinical practice. Retesting of RAS status during treatment should be discussed in patients with unusual long-term clinical courses of RAS MT mCRC to optimise treatment strategy and to evaluate the use of anti-EGFR antibodies.

Clinical Impact of Primary Tumor Location in Metastatic Colorectal Cancer Patients Under Later-Line Regorafenib or Trifluridine/Tipiracil Treatment

Background

Primary tumor location (PTL) is an important prognostic and predictive factor in the first-line treatment of metastatic colorectal cancer (mCRC). Although regorafenib (REG) and trifluridine/tipiracil (FTD/TPI) have been introduced recently, the clinical impact of PTL in these treatments is not well understood.

Materials and Methods

We retrospectively evaluated patients with mCRC who were registered in a multicenter observational study (the REGOTAS study). The main inclusion criteria were Eastern Cooperative Oncology Group performance status (ECOG PS) of 0-2, refractory or intolerant to fluoropyrimidines, oxaliplatin, irinotecan, angiogenesis inhibitors, anti-epidermal growth factor receptor therapy (if RAS wild-type), and no prior use of REG and FTD/TPI. The impact of PTL on overall survival (OS) was evaluated using Cox proportional hazard models based on baseline characteristics.

Results

A total of 550 patients (223 patients in the REG group and 327 patients in the FTD/TPI group) were included in this study, with 122 patients with right-sided tumors and 428 patients with left-sided tumors. Although the right-sided patients had significantly shorter OS compared with the left-sided patients by univariate analysis (p = 0.041), a multivariate analysis revealed that PTL was not an independent prognostic factor (hazard ratio, 0.95; p = 0.64). In a subgroup analysis, the OS was comparable between the REG and FTD/TPI groups regardless of PTL (p for interactions = 0.60).

Conclusions

In the present study, PTL is not a prognostic and predictive factor in patients with mCRC under later-line REG or FTD/TPI therapy.

Newly Obtained Apple Pectin as an Adjunct to Irinotecan Therapy of Colorectal Cancer Reducing E. coli Adherence and β-Glucuronidase Activity

Colorectal cancer (CRC) is the second cause of cancer death worldwide. The composition and enzymatic activity of colonic microbiota can significantly affect the effectiveness of CRC chemotherapy. Irinotecan is a drug widely used to treat colon cancer. However, the transformation of a drug-glucuronide (SN-38G) back to its active form (SN-38) by bacterial β-glucuronidase (GUS) constitutes the primary reason for the observed intestinal toxicity of irinotecan. It was demonstrated that novel enzymatically extracted apple pectin (PC) might be a promising candidate for an adjunct to irinotecan therapy. PC itself reduced the viability of HCT 116 and Caco-2 colorectal cancer cells, induced apoptosis, and increased intracellular reactive oxygen species production. Moreover, PC enhanced the cytotoxic and proapoptotic effect of irinotecan (at concentrations below its IC₅₀), i.e., synergistic effect was recorded. Additionally, PC exhibited potent anti-inflammatory properties and prevented adhesion of prototype adherent-invasive E. coli (AIEC) LF82 strain and laboratory K-12_C600 strain to colon cancer cells. PC was also identified to be an effective inhibitor of bacterial GUS activity. Altogether, novel apple pectin was identified as a promising candidate for a supplement to irinotecan therapy that might alleviate its side-effects via inhibition of bacterial GUS and thus increasing its therapeutic efficacy.

Detection and Clinical Value of Circulating Tumor Cells as an Assisted Prognostic Marker in Colorectal Cancer Patients

BACKGROUND

Circulating tumor cells (CTCs) are cells that have been shed into the vasculature from a primary tumor and circulate in the bloodstream. It has been suggested that detecting CTCs could help the clinician to detect early metastasis or recurrence more effectively. This trial sets out to assess the detection and clinical value of CTCs as an assisted prognostic marker in patients with colon cancer and rectal cancer.

METHODS

A prospective cohort of patients with colorectal cancer (CRC) was enrolled from July 2015 to February 2018 in Shanghai Minimally Invasive Surgery Center, Shanghai, China. In this study, 149 patients with CRC were enrolled and underwent surgical treatment. There were 79 cases of colon cancer and 70 cases of rectal cancer, including 93 males and 56 females. To investigate the correlativity and clinical value of CTCs, the patients were statistically analyzed in different subgroups: colon cancer group vs rectal cancer group, and left hemicolon cancer group vs right hemicolon cancer group.

RESULTS

The results of analysis comparing CTC counts and clinical pathological features in colon and rectal cancer indicated that with increased tumor stage, the number of CTCs also increased, with significant statistical differences. CTC counts in patients with colon and rectal cancer showed positive correlations with TNM staging (P=0.001, 0.013, respectively), T staging (P=0.021, 0.001), N staging (P=0.014, 0.035) and M staging (P=0.018, 0.203). Detection of serum biomarkers in CTC-positive and CTC-negative groups indicated a significantly increasing expression in the CTC-positive group. To confirm the correlations between CTCs and histoembryological differences, analysis was conducted with the patients in two subgroups: left hemicolon cancer group and right hemicolon cancer group. The results showed that the positive rate of CTCs increased in both groups with the increase in tumor stage. The survival analysis indicated that there was a steep gradient in survival in the follow-up period, particularly in the CTC-positive group (P=0.000). Risk assessment curves showed that the change escalated more rapidly in the CTC-positive group. Furthermore, with the increase in T stage, changes in the survival curve and risk curve escalated more rapidly in the CTC-positive group.

CONCLUSION

It was confirmed that in the left hemicolon cancer group, a much higher coincidence rate could be found on CTC-positive rate and clinicopathological features, than in the right hemicolon cancer group. The sensitivity of CTCs may be related to the histoembryological location of the tumor, lymphatic metastasis and the depth of infiltration. Monitoring CTCs may have value in evaluating clinical staging and estimating clinical prognosis.

Relationship between stromal regulatory T cells and the response to neoadjuvant chemotherapy for locally advanced rectal cancer

BACKGROUND

In addition to the direct power of anticancer drugs, the effectiveness of anticancer therapy depends on the host immune function. The present study investigated whether or not the reduction rate and histological response of preoperative chemotherapy were related to the immune microenvironment surrounding a primary tumor of the rectum.

METHODS

Sixty-five patients received preoperative chemotherapy followed by resection from 2012 to 2014; all of these patients were retrospectively analyzed. CD3, CD8, and FoxP3 were immunohistochemically examined as markers for T lymphocytes, cytotoxic T lymphocytes, and regulatory T lymphocytes (Treg), respectively. The correlation between the tumor-infiltrating lymphocyte composition and the tumor reduction rate and histological response to neoadjuvant chemotherapy was investigated.

RESULTS

The average tumor reduction rate was 41.5% ± 18.8%. According to RECIST, 47 patients (72.3%) achieved a partial response (PR), and 1 patient (1.5%) achieved a complete response (CR). Eight patients (12.3%) showed a grade 2 histological response, and 2 (3.1%) showed a grade 3 response. A multivariate analysis demonstrated that a low Treg infiltration in stromal cell areas was significantly associated with the achievement of a PR or CR [odds ratio (OR) 7.69; 95% confidence interval (CI) 1.96-33.33; p < 0.01] and a histological grade 2 or 3 response (OR 11.11; 95% CI 1.37-98.04; p = 0.02).

CONCLUSION

A low Treg infiltration in the stromal cell areas may be a marker of a good response to neoadjuvant chemotherapy in patients with locally advanced rectal cancer.

Risk stratification and goal of systemic therapy for successful surgical management of colorectal liver metastases: Oncological optimization

For patients with stage IV colorectal cancer (CRC), curative-intent surgery has actively been performed for expecting prolonged survival outcomes. However, because the population with stage IV CRC is considerably heterogeneous, optimal selection of surgical candidate is inevitable to maximize survival outcomes. In the era of effective chemotherapy, there is an increasing need for a strategic use of chemotherapy as a part of multidisciplinary treatment to expand surgical indications and enhance the clinical outcomes. However, since the fate of each patient is difficult to predict at initial presentation, our clinical practice is rather "tailored", considering the anatomy, oncological behavior of tumor, response to chemotherapy, and patient's physical status. Given that surgery is the only treatment option for expecting cure of colorectal liver metastases (CLM), the main purpose of chemotherapy for potentially/marginally resectable disease is to clarify the likelihood of surgical benefit through testing the behavior of the tumor and to select an appropriate candidate for surgery. This process of clinical decision is actually optimization of the initial population for surgery through the optimization of treatment for each patient. In this article, theoretical bases of multidisciplinary management for CLM were revisited and the concept of "oncological optimization" underling our clinical decision was discussed.

Shared decision-making and patient decision aids in choosing first-line targeted therapy for metastatic colorectal cancer in Taiwan

INTRODUCTION

In Taiwan, given the discrepancy between current treatment guidelines and reimbursement options, patients might require a tool to support their decision-making process when selecting a regimen for metastatic colorectal cancer, especially therapeutic strategies, and subsequent costs, along with efficacy and safety outcomes. Therefore, we developed a patient decision aid (PDA) to support patients in choosing between treatment options recommended based on the current evidence and those reimbursed by the Taiwanese National Health Insurance.

METHODS

By carefully reviewing the updated data and then interpreting the clinical tool, we conducted a needs assessment using a serial questionnaire to test for a step-by-step adjustment of the PDA.

RESULTS

Patients, their relatives, and medical team members were most concerned about outcomes, such as overall survival, progression-free survival, objective response rate, tumor shrinkage to resectable status, total medical cost, severe gastrointestinal perforation, and severe skin reaction. After a serial alpha test for quality, we performed quantitative evaluation and beta tests, revealing average scores of more than 4 points (on a scale of 1-5) for both perceptibility and utility.

CONCLUSIONS

The present findings suggest that PDAs are useful and supplement the shared decision-making practice, helping patients make decisions about preferences and consider the pros and cons of treatment regimens, along with insurance reimbursement options.

Metastatic colo-rectal cancer: real life experience from an Indian tertiary care center

Background

No data exist for the long-term outcome of metastatic colorectal cancer (mCRC) from the Southern part of Asia. The primary objective of the study is to evaluate the survival outcome of mCRC from an Indian tertiary care center. The study also aims to highlight the treatment pattern practiced and the unique clinico-pathologic characteristics.

Methods

This is a single-center retrospective observational study done at a large referral tertiary care center in North India. All patients with synchronous or metachronous mCRC who received at least one dose of chemotherapy for metastatic disease, registered between 2003 to 2017 were included. Primary outcome measures were overall survival and progression-free survival and prognostic factors of overall survival. Descriptive analysis was done for the clinicopathological characteristics and treatment patterns. Kaplan Meier method for overall survival and progression-free survival. Cox regression analysis was performed for the determination of the prognostic factors for overall survival.

Result

Out of 377 eligible patients, 256 patients (68%) had de novo metastatic disease and the remaining 121 (32%) progressed to metastatic disease after initial treatment. The cohort was young (median age, 46 years) with the most common primary site being the rectum. A higher proportion of signet (9%) and mucinous histology (24%). The three common sites of metastasis were the liver, peritoneum, and lung. In the first line, most patients received oxaliplatin-based chemotherapy (70%). Only 12.5% of patients received biologicals in the first-line setting. The median follow-up and median overall survival of study cohort were 17 months and 18.5 months. The factors associated with poor outcome for overall survival on multivariate analysis were ECOG performance status of > 1, high CEA, low albumin, and the number of lines of chemotherapy received (< 2).

Conclusion

The outcome of mCRC is inferior to the published literature. We found a relatively higher proportion of patients with the following characteristics; younger, rectum as primary tumor location, the signet, and mucinous histology, higher incidence of peritoneum involvement. The routine use of targeted therapies is limited. Government schemes (inclusion of targeted therapies in the Ayushman scheme), NGO assistance, and availability of generic low-cost targeted drugs may increase the availability.

Use of real-world evidence for oncology clinical decision making in emerging economies

Real-world evidence (RWE) can provide insights into patient profiles, disease detection, treatment choice, dosing strategies, treatment sequencing, adverse event management and financial toxicity associated with oncology treatment. However, the full potential of RWE is untapped in emerging economies due to structural and behavioral factors. Structural barriers include lack of regulatory engagement, real-world data availability, quality and integrity. Behavioral barriers include entrenched healthcare professional behaviors that impede rapid RWE understanding and adoption. These barriers can be addressed with close collaboration of healthcare stakeholders; of whom, regulators need to be at the forefront given their ability to facilitate use of RWE in healthcare policy and legislation.

Care Patterns and Overall Survival in Patients With Early-Onset Metastatic Colorectal Cancer

PURPOSE

Colorectal cancer (CRC) incidence in patients younger than 50 years of age, commonly defined as early-onset (EO-CRC), is rising. EO-CRC often presents with distinct clinicopathologic features. However, data on prognosis are conflicting and outcomes with modern treatment approaches for metastatic disease are still limited.

MATERIALS AND METHODS

We prospectively enrolled patients with metastatic CRC (mCRC) to a biobanking and clinical data collection protocol from 2014 to 2018. We grouped the cohort based on age at initial diagnosis: < 40 years, 40-49 years, and ≥ 50 years. We used regression models to examine associations among age at initial diagnosis, treatments, clinicopathologic features, and survival.

RESULTS

We identified 466 patients with mCRC (45 [10%] age < 40 years, 109 [23%] age 40-49 years, and 312 [67%] age ≥ 50 years). Patients < 40 years of age were more likely to have received multiple metastatic resections (odds ratio [OR], 3.533; P = .0066) than their older counterparts. Patients with EO-CRC were more likely to receive triplet therapy than patients > 50 years of age (age < 40 years: OR, 6.738; P = .0002; age 40-49 years: OR, 2.949; P = .0166). Patients 40-49 years of age were more likely to have received anti-EGFR therapy (OR, 2.633; P = .0016). Despite differences in care patterns, age did not predict overall survival.

CONCLUSION

Despite patients with EO-CRC receiving more intensive treatments, survival was similar to the older counterpart. However, EO-CRC had clinical and molecular features associated with worse prognoses. Improved biologic understanding is needed to optimize clinical management of EO-CRC. The cost-benefit ratio of exposing patients with EO-CRC to more intensive treatments has to be carefully evaluated.

Mechanisms of Immune Escape and Resistance to Checkpoint Inhibitor Therapies in Mismatch Repair Deficient Metastatic Colorectal Cancers

Simple Summary

A subset of colorectal cancers (CRCs) is characterized by a mismatch repair deficiency that is frequently associated with microsatellite instability (MSI). The compromised DNA repair machinery leads to the accumulation of tumor neoantigens affecting the sensitivity of MSI metastatic CRC to immune checkpoint inhibitors (CPIs), both upfront and in later lines of treatment. However, up to 30% of MSI CRCs exhibit primary resistance to frontline immune based therapy, and an additional subset develops acquired resistance. Here, we first discuss the clinical and molecular features of MSI CRCs and then we review how the loss of antigenicity, immunogenicity, and a hostile tumor microenvironment could influence primary and acquired resistance to CPIs. Finally, we describe strategies to improve the outcome of MSI CRC patients upon CPI treatment.

Abstract

Immune checkpoint inhibitors (CPIs) represent an effective therapeutic strategy for several different types of solid tumors and are remarkably effective in mismatch repair deficient (MMRd) tumors, including colorectal cancer (CRC). The prevalent view is that the elevated and dynamic neoantigen burden associated with the mutator phenotype of MMRd fosters enhanced immune surveillance of these cancers. In addition, recent findings suggest that MMRd tumors have increased cytosolic DNA, which triggers the cGAS STING pathway, leading to interferon-mediated immune response. Unfortunately, approximately 30% of MMRd CRC exhibit primary resistance to CPIs, while a substantial fraction of tumors acquires resistance after an initial benefit. Profiling of clinical samples and preclinical studies suggests that alterations in the Wnt and the JAK-STAT signaling pathways are associated with refractoriness to CPIs. Intriguingly, mutations in the antigen presentation machinery, such as loss of MHC or Beta-2 microglobulin (B2M), are implicated in initial immune evasion but do not impair response to CPIs. In this review, we outline how understanding the mechanistic basis of immune evasion and CPI resistance in MMRd CRC provides the rationale for innovative strategies to increase the subset of patients benefiting from CPIs.