Neoadjuvant treatment of colorectal cancer: comprehensive review

BACKGROUND

Neoadjuvant therapy has an established role in the treatment of patients with colorectal cancer. However, its role continues to evolve due to both advances in the available treatment modalities, and refinements in the indications for neoadjuvant treatment and subsequent surgery.

METHODS

A narrative review of the most recent relevant literature was conducted.

RESULTS

Short-course radiotherapy and long-course chemoradiotherapy have an established role in improving local but not systemic disease control in patients with rectal cancer. Total neoadjuvant therapy offers advantages over short-course radiotherapy and long-course chemoradiotherapy, not only in terms of increased local response but also in reducing the risk of systemic relapses. Non-operative management is increasingly preferred to surgery in patients with rectal cancer and clinical complete responses but is still associated with some negative impacts on functional outcomes. Neoadjuvant chemotherapy may be of some benefit in patients with locally advanced colon cancer with proficient mismatch repair, although patient selection is a major challenge. Neoadjuvant immunotherapy in patients with deficient mismatch repair cancers in the colon or rectum is altering the treatment paradigm for these patients.

CONCLUSION

Neoadjuvant treatments for patients with colon or rectal cancers continue to evolve, increasing the complexity of decision-making for patients and clinicians alike. This review describes the current guidance and most recent developments.

Temporal trends and regional variability in BRAF and KRAS genetic testing in Denmark (2010-2022): Implications for precision medicine

OBJECTIVE

This study aims to evaluate the developments in the testing of Kirsten Rat Sarcoma viral oncogene homolog (KRAS) and v-Raf murine sarcoma viral oncogene homolog B1 (BRAF) mutations across different cancer types and regions in Denmark from 2010 to 2022.

STUDY DESIGN AND SETTING

Using comprehensive data from the Danish health registries, we linked molecular test results from the Danish Pathology Registry with cancer diagnoses from the Danish National Patient Registry between 2010 and 2022. We assessed the frequency and distribution of KRAS and BRAF mutations across all cancer types, years of testing, and the five Danish regions.

RESULTS

The study included records of KRAS testing for 30 671 patients and BRAF testing for 30 860 patients. Most KRAS testing was performed in colorectal (78%) and lung cancer (18%), and BRAF testing in malignant melanoma (13%), colorectal cancer (67%), and lung cancer (12%). Testing rates and documentation mutational subtypes increased over time. Reporting of wildtype results varied between lung and colorectal cancer, with underreporting in lung cancer. Regional variations in testing and reporting were observed.

CONCLUSION

Our study highlights substantial progress in KRAS and BRAF testing in Denmark from 2010 to 2022, evidenced by increased and more specific reporting of mutational test results, thereby improving the precision of cancer diagnosis and treatment. However, persistent regional variations and limited testing for cancer types beyond melanoma, colorectal, and lung cancer highlight the necessity for a nationwide assessment of the optimal testing approach.

TRIFLURIDINE/TIPIRACIL (FTD/TPI) with or without bevacizumab in previously treated patients with esophago-gastric adenocarcinoma, a randomised phase III trial

Background

Trifluridine-tipiracil has shown a survival benefit compared with placebo in patients with chemorefractory metastatic esophago-gastric adenocarcinoma. We aimed to compare the efficacy of trifluridine-tipiracil plus bevacizumab vs trifluridine-tipiracil monotherapy in pre-treated patients with metastatic esophago-gastric adenocarcinoma.

Methods

This investigator-initiated, open-label, randomized trial enrolled patients with metastatic esophago-gastric adenocarcinoma. The main inclusion criteria were patients with pre-treated metastatic esophago-gastric adenocarcinoma, and WHO performance status 0 or 1. Participants were randomly assigned (1:1) to receive oral trifluridine-tipiracil (35 mg/m2 twice daily on days 1-5 and 8-12 every 28 days) alone or combined with bevacizumab (5 mg/kg on days 1 and 15) until progression, unacceptable toxicity, or patient decision to withdraw. Randomisation was stratified by sex and treatment line. The primary endpoint was investigator-evaluated progression-free survival. All analyses were based on intention to treat. This trial is registered with EudraCT, 2018-004845-18.

Findings

From Oct 1, 2019, to Sept 30, 2021, 103 patients were enrolled and randomly assigned to trifluridine-tipiracil (n = 53) or trifluridine-tipiracil plus bevacizumab (n = 50). The clinical cut-off date was March 1st, 2023, after a median follow-up of 36.6 months. Median progression-free survival was 3.1 months (95% CI 2.0-4.3) in the trifluridine-tipiracil group vs 3.9 months (3.0-6.3) in the trifluridine-tipiracil plus bevacizumab group (hazard ratio 0.68, 95% CI 0.46-1.02; p = 0.058). The most frequent grade 3 or worse adverse event was neutropenia, observed in 26 (49%) patients in the trifluridine-tipiracil group vs 23 patients (46%) in the trifluridine-tipiracil plus bevacizumab group. At least one hospitalization was observed in 21 patients (40%) in the trifluridine-tipiracil group and 22 patients (44%) in the trifluridine-tipiracil plus bevacizumab group. No deaths were deemed treatment related.

Interpretation

In patients with pre-treated metastatic esophago-gastric cancer, trifluridine-tipiracil plus bevacizumab, compared to trifluridine-tipiracil monotherapy, did not significantly prolong progression-free survival. The combination of trifluridine-tipiracil with bevacizumab was well tolerated without increase in severe neutropenia and no new safety signals.

Funding

Servier, Roche.

Age-related differences in cancer biology in older patients

Older cancer patients are more often than younger diagnosed via an unplanned hospital admission which may negatively influence the prognosis. An increasing number of cancers is expected due to ageing of populations, and these phenomena are likely to result in an increase in older cancer patients with multiple complications, extended hospital stays, and reduced quality of life and survival. In this review, we present recent data about routes to cancer diagnosis for older vs younger patients to emphasize that diagnostic pathways need improvements to avoid an increase in unplanned hospital admissions due to cancer.

Variations in the definition and perceived importance of positive resection margins in patients with colorectal cancer - an EYSAC international survey

INTRODUCTION

Microscopically positive resection margins (R1) are associated with poorer outcomes in patients with colorectal cancer. However, different definitions of R1 margins exist. It is unclear to what extent the definitions used in everyday clinical practice differ within and between nations. This study sought to investigate variations in the definition of R1 margins in colorectal cancer and the importance of margin status in clinical decision-making.

MATERIALS AND METHODS

A 14-point survey was developed by members of The European Society of Surgical Oncology (ESSO) Youngs Surgeons and Alumni Club (EYSAC) Research Academy targeting all members of the multidisciplinary team (MDT) treating patients with colorectal cancer. The survey was distributed on social media, in ESSO's monthly newsletter and via national societies.

RESULTS

In total, 137 responses were received. Most respondents were from Europe (89.7%), with the majority from Denmark (56.9%). Less than 2/3 of respondents defined R1 margins as the presence of viable cancer cells ≤1 mm of the margin. Only 60% reported that subdivisions of R1 margins (primary tumour vs tumour deposit vs metastatic lymph node) are routinely available. More than 20% of respondents reported that pathology reports are not routinely reviewed at MDT meetings. Less than half of respondents considered margin status in decision-making for type and duration of adjuvant chemotherapy in Stage III colon cancer.

CONCLUSION

The definitions and perceived clinical importance of microscopically positive margins in patients with colorectal cancer appear to vary. Adoption of an international dataset for pathology reporting may help to standardise current practices.

Impact of adjuvant chemotherapy on long-term overall survival in patients with high-risk stage II colon cancer: a nationwide cohort study

BACKGROUND

This study aimed to investigate the impact of adjuvant chemotherapy on long-term survival in unselected patients with high-risk stage II colon cancer including an analysis of each high-risk feature.

MATERIALS AND METHODS

Data from the Danish Colorectal Cancer Group, the National Patient Registry and the Danish Pathology Registry from 2014 to 2018 were merged. Patients surviving > 90 days were included. High-risk features were defined as emergency presentation, including self-expanding metal stents (SEMS)/loop-ostomy as a bridge to resection, grade B or C anastomotic leakage, pT4 tumors, lymph node yield < 12 or signet cell carcinoma. Eligibility criteria for chemotherapy were age < 75 years, proficient MMR gene expression, and performance status ≤ 2. The primary outcome was 5-year overall survival. Secondary outcomes included the proportion of eligible patients allocated for adjuvant chemotherapy and the time to first administration.

RESULTS

In total 939 of 3937 patients with stage II colon cancer had high-risk features, of whom 408 were eligible for chemotherapy. 201 (49.3%) patients received adjuvant chemotherapy, with a median time to first administration of 35 days after surgery. The crude 5-year overall survival was 84.9% in patients receiving adjuvant chemotherapy compared with 66.3% in patients not receiving chemotherapy, p < 0.001. This association corresponded to an absolute risk difference of 14%.

CONCLUSION

5-year overall survival was significantly higher in patients with high-risk stage II colon cancer treated with adjuvant chemotherapy compared with no chemotherapy. Adjuvant treatment was given to less than half of the patients who were eligible for it.

Evaluating the efficacy and safety of neoadjuvant pembrolizumab in patients with stage I-III MMR-deficient colon cancer: a national, multicentre, prospective, single-arm, phase II study protocol

INTRODUCTION

Within the last two decades, major advances have been made in the surgical approach for patients with colorectal cancer. However, to this day we face considerable challenges in reducing surgery-related complications and improving long-term oncological outcomes. Unprecedented response rates have been achieved in studies investigating immunotherapy in patients with mismatch repair deficient (dMMR) colorectal cancer. This has raised the question of whether neoadjuvant immunotherapy may change the standard of care for localised dMMR colon cancer and pave the way for organ-sparing treatment.

METHODS AND ANALYSIS

This is an investigator-initiated, multicentre, prospective, single-arm, phase II study in patients with stage I-III dMMR colon cancer scheduled for intended curative surgery. Eighty-five patients will be treated with one dose of pembrolizumab (4 mg/kg) and within 5 weeks will undergo a re-evaluation with an endoscopy and a CT scan-to assess tumour response-before standard resection of the tumour. The primary endpoint is the number of patients with pathological complete response, and secondary endpoints include safety (number and severity of adverse events) and postoperative surgical complications. In addition, we aspire to identify predictive biomarkers that can point out patients that achieve pathological complete response.

ETHICS AND DISSEMINATION

The Regional Committee for Health Research and Ethics and the Danish Medicines Agency have approved this study. The study will be performed according to the Helsinki II declaration. Written informed consent will be obtained from all participants. The results of the study will be submitted to peer-reviewed journals for publication and presented at international congresses.

TRIAL REGISTRATION NUMBER

NCT05662527.

Differences in adjuvant chemotherapy and oncological outcomes according to margin status in patients with stage III colon cancer

BACKGROUND

Microscopically positive margins to lymph node metastases (R1LNM) are associated with poorer oncological outcomes in patients with Stage 3 colon cancer. These poorer outcomes were seen despite a greater proportion of these patients receiving adjuvant chemotherapy when compared to those with microscopically negative (R0) margins. We sought to determine if differences in the type or duration of adjuvant chemotherapy could account for the differences in outcomes seen between patients with R0 and R1LNM margins.

METHODS

A multicentre retrospective study including patients undergoing surgery for Stage 3 colon cancer between 2016-2019 at specialist centres. Patients were stratified according to margins status (R0 vs R1LNM). Type/duration of chemotherapy and oncological outcomes were compared between groups.

RESULTS

718 patients were included, of whom 100 had R1LNM margins (13.1%). Patients with R1LNM margins had significantly poorer 3-year distant metastases-free (R0 78.2% (95% CI 74.5-81.3) versus R1LNM 58.8% (95% CI 47.2-68.6), p < 0.001) and disease specific survival (R0 88.3% (95% CI 85.2-90.9) versus R1LNM 78.5% (95% CI 68.0-85.8), p < 0.001) when compared to those with R0 margins. No differences were noted in the proportion of patients who completed long-course chemotherapy or were treated with oxaliplatin-based combinations between the R1LNM and R0 groups. Differences in outcomes between R0 and R1LNM groups persisted even when only those patients who completed long-course chemotherapy were compared.

DISCUSSION

Differences in adjuvant chemotherapy do not appear to account for the poorer oncological outcomes seen in patients with R1LNM margins after surgery for Stage 3 colon cancer. This suggests that adjuvant chemotherapy may be less effective in this patient group. Further studies to elucidate a potential biological basis for this difference are warranted.

Therapy with pembrolizumab in treatment-naïve patients with nonmetastatic, mismatch repair deficient colorectal cancer

Therapy with immune checkpoint inhibitors (ICI) is effective in patients with metastatic mismatch-repair deficient (dMMR) colorectal cancer (CRC); however, data on treatment with neoadjuvant ICI in patients with locally advanced CRC are limited. From March 2019 to June 2020, five Danish oncological centers treated 10 patients with a treatment-naïve dMMR CRC with preoperative pembrolizumab, 9 with a nonmetastatic, unresectable colon cancer and 1 with a locally advanced rectum cancer. All 10 patients were evaluated regularly at a multidisciplinary team (MDT) meeting, and they all had a radical resection after a median of 8 cycles (range 2-13) of pembrolizumab. A microscopic evaluation of the resected tumors revealed no remaining tumor cells in five patients, while five still had tumor cells present. The patients were given no additional therapy. No recurrences were reported after a median follow-up of 26 months (range 23-38.5 months). Biopsies from Danish patients with CRC are routinely screened for dMMR proteins. In 2017, data from the Danish Colorectal Cancer Group showed that 19% (565/3000) of the patients with colon cancer and 1.5% (19/1279) of those with rectum cancer had an dMMR tumor. Among the patients with MMR determination, 26% (99/384) patients had a T4 dMMR colon cancer; thus, the 10 patients treated with neoadjuvant pembrolizumab comprised about 9% of the patients with a T4 dMMR colon cancer (9/99) and 5% of patients with dMMR rectal cancer (1/19). Therapy with pembrolizumab was feasible and effective. Larger prospective trials are needed to confirm our findings.

Implementation and clinical benefit of DPYD genotyping in a Danish cancer population

BACKGROUND

In 2020, the European Medicines Agency recommended testing patients for dihydropyrimidine dehydrogenase (DPD) deficiency before systemic treatment with fluoropyrimidines (FP). DPD activity testing identifies patients at elevated risk of severe FP-related toxicity (FP-TOX). The two most used methods for DPD testing are DPYD genotyping and DPD phenotyping (plasma uracil concentration). The primary objective of this study was to compare the overall frequency of overall grade ≥3 FP-TOX before and after the implementation of DPYD genotyping.

PATIENTS AND METHODS

Two hundred thirty Danish, primarily gastrointestinal cancer patients, were DPYD-genotyped before their first dose of FP, and blood was sampled for post hoc assessment of P-uracil. The initial dose was reduced for variant carriers. Grade ≥3 FP-TOX was registered after the first three treatment cycles of FP. The frequency of toxicity was compared to a historical cohort of 492 patients with post hoc determined DPYD genotype from a biobank.

RESULTS

The frequency of overall grade ≥3 FP-TOX was 27% in the DPYD genotype-guided group compared to 24% in the historical cohort. In DPYD variant carriers, DPYD genotyping reduced the frequency of FP-related hospitalization from 19% to 0%. In the control group, 4.8% of DPYD variant carriers died due to FP-TOX compared to 0% in the group receiving DPYD genotype-guided dosing of FP. In the intervention group, wild-type patients with uracil ≥16 ng/ml had a higher frequency of FP-TOX than wild-type patients with uracil <16 ng/ml (55% versus 28%).

CONCLUSIONS

We found no population-level benefit of DPYD genotyping when comparing the risk of grade ≥3 FP-TOX before and after clinical implementation. We observed no deaths or FP-related hospitalizations in patients whose FP treatment was guided by a variant DPYD genotype. The use of DPD phenotyping may add valuable information in DPYD wild-type patients.

Prognostic value of baseline functional status measures and geriatric screening in vulnerable older patients with metastatic colorectal cancer receiving palliative chemotherapy - The randomized NORDIC9-study

INTRODUCTION

Appropriate patient selection based on functional status is crucial when considering older adults for palliative chemotherapy. This pre-planned analysis of the randomized NORDIC9-study explored the prognostic value of four functional status measures regarding progression-free survival (PFS) and overall survival (OS) in vulnerable older patients with metastatic colorectal cancer (mCRC) receiving first-line palliative chemotherapy.

MATERIALS AND METHODS

Patients ≥70 years of age with mCRC not candidates for standard full-dose combination chemotherapy were randomized to receive full-dose S1 or reduced-dose S1 + oxaliplatin. At baseline, functional status was assessed using ECOG performance status (ECOG PS), frailty phenotype, Geriatric 8 (G8), and Vulnerable Elderly Survey-13 (VES-13). Multivariable regression models were applied and C-statistics were estimated.

RESULTS

In total, 160 patients with a median age of 78 years (IQR: 76-81) were included. While in univariate analyses, ECOG PS, frailty phenotype, and VES-13 were statistically significantly associated with differences in OS between subgroups, G8 was not (HR = 1.55, 95%CI: 0.99-2.41, p = 0.050). In multivariable analyses adjusted for age, sex, body mass index, and treatment allocation, we found significant differences between subgroups for all applied tools and with C-statistics in the moderate range for ECOG PS and VES-13. Concerning PFS, statistically significant differences were observed between subgroups of ECOG PS, G8, and VES-13 both in uni- and multivariable analyses, but not for frailty phenotype.

DISCUSSION

In this Nordic cohort of vulnerable older patients with mCRC, baseline ECOG PS, frailty phenotype, G8, and VES-13 showed prognostic value regarding overall survival, and moderate predictive value of models based on ECOG PS and VES-13 was demonstrated.

A phase II study of daily encorafenib in combination with biweekly cetuximab in patients with BRAF V600E mutated metastatic colorectal cancer: the NEW BEACON study

BACKGROUND

Patients with BRAF V600E mutated metastatic colorectal cancer (mCRC) have a poor prognosis. The introduction of BRAF targeted therapy with encorafenib and weekly administered cetuximab have shown improved survival with a median progression free survival (PFS) of 4.3 months. However, a regimen with cetuximab given every second week may have comparable efficacy and is more convenient for patients. While BRAF targeted therapy is a new standard therapy in pre-treated patients with BRAF V600E mutated mCRC, resistance invariably occurs and is an emerging challenge. The aim of this study is to investigate the efficacy and tolerability of cetuximab given every second week in combination with daily encorafenib and to explore the correlation between markers of resistance and outcome.

METHODS

The study is an open label, single arm, phase II study, investigating the efficacy and tolerability of cetuximab given every second week in combination with encorafenib in patients with BRAF V600E mutated mCRC. Furthermore, we will be investigating mechanisms of response and resistance against BRAF targeted therapy though comprehensive genomic profiling on tumor tissue and blood for circulating tumor DNA analysis. A total of 53 patients (19 + 34 in two steps) will be included according to Simon's optimal two stage design. The primary end point of the study is 2 months PFS rate.

DISCUSSION

By combining BRAF inhibitor with cetuximab given every second week we can halve the number of visits in the hospital compared to the currently approved regimen with weekly cetuximab. This seems particularly relevant in a group of patients with a median overall survival of 9.3 months. Resistance after initial response to targeted therapy can be either adaptive (e.g., epigenetic, or transcriptomic alterations) or acquired (selective genetic alterations - e.g., activating de novo mutations) resistance. It is of great importance to untangle these complex mechanisms of resistance in patients with BRAF V600E mutated mCRC to improve treatment strategies in the future potentially even further.

TRIAL REGISTRATION

EU Clinical Trial Register, Eudract no. 2020-003283-10 . Registered on 11 November 2020.

Extensive genomic analysis in patients with KRAS-mutated solid tumors shows high frequencies of concurrent alterations and potential targets but has limited clinical impact

BACKGROUND

This study aimed to investigate the distribution and frequency of concurrent alterations in different cancers across KRAS subtypes and in different KRAS subtypes across cancers, and to identify potentially actionable targets and patients who received targeted treatment matched to their genomic profile (GP).

MATERIALS AND METHODS

In this descriptive and single-center study, we included 188 patients with solid tumors harboring KRAS mutations in codon 12, 13, 61, 117, or 146, referred to the Phase 1 Unit, Rigshospitalet, Copenhagen, Denmark from mid-2016 to 2020. Genomic co-alterations were detected with whole-exome sequencing, RNA sequencing, SNP array, and mRNA expression array on fresh biopsies. The study is part of the Copenhagen Prospective Personalized Oncology study (NCT02290522).

RESULTS

The majority of patients had colorectal cancer (60.1%), non-small cell lung cancer (11.2%), or pancreatic cancer (10.6%). Most tumors were KRAS-mutated in codon 12 or 13 (93.7%) including G12D (27.1%), G12V (26.6%), G12C (11.7%), and G13D (11.2%). A total of 175 different co-alterations were found, most frequently pathogenic APC and TP53 mutations (55.9% and 46.4%, respectively) and high expression of CEACAM5 (73.4%). Different cancers and KRAS subtypes showed different patterns of co-alterations, and 157 tumors (83.5%) had potentially actionable targets with varying evidence of targetability (assessed using ESMO Scale for Clinical Actionability of molecular Targets). Of the 188 patients included in the study, 15 (7.4%) received treatment matched to their GP (e.g., immunotherapy and synthetic lethality drugs), of whom one had objective partial response according to Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1.

CONCLUSION

Performing extensive genomic analysis in patients with known KRAS-mutated solid tumors may contribute with information to the genomic landscape of cancers and identify targets for immunotherapy or synthetic lethality drugs, but currently appears to have overall limited clinical impact, as few patients received targeted therapy matched to their GP.

DPYD genotyping and dihydropyrimidine dehydrogenase (DPD) phenotyping in clinical oncology. A clinically focused minireview

BACKGROUND

In clinical oncology, systemic 5-fluorouracil (5-FU) and its oral pro-drugs are used to treat a broad group of solid tumours. Patients with dihydropyrimidine dehydrogenase (DPD) enzyme deficiency are at elevated risk of toxicity if treated with standard doses of 5-FU. DPYD genotyping and measurements of plasma uracil concentration (DPD phenotyping) can be applied as tests for DPD deficiency. In April 2020, the European Medicines Agency recommended pre-treatment DPD testing to reduce the risk of 5-FU-related toxicity.

OBJECTIVES

The objective of this study is to present the current evidence for DPD testing in routine oncological practice.

METHODS

Two systematic literature searches were performed following the PRISMA guidelines. We identified studies examining the possible benefit of DPYD genotyping or DPD phenotyping on the toxicity risk.

FINDINGS

Nine and 12 studies met the criteria for using DPYD genotyping and DPD phenotyping, respectively.

CONCLUSIONS

The evidence supporting either DPYD genotyping or DPD phenotyping as pre-treatment tests to reduce 5-FU toxicity is poor. Further evidence is still needed to fully understand and guide clinicians to dose by DPD activity.

The Prognostic Value of Pre-Treatment Circulating Biomarkers of Systemic Inflammation (CRP, dNLR, YKL-40, and IL-6) in Vulnerable Older Patients with Metastatic Colorectal Cancer Receiving Palliative Chemotherapy-The Randomized NORDIC9-Study

Appropriate patient selection for palliative chemotherapy is crucial in patients with metastatic colorectal cancer (mCRC). We investigated the prognostic value of C-reactive protein (CRP), derived neutrophil-to-lymphocyte ratio (dNLR), Interleukin (IL)-6, and YKL-40 on progression-free survival (PFS) and overall survival (OS) in the NORDIC9 cohort. The randomized NORDIC9-study included patients ≥70 years with mCRC not candidates for standard full-dose combination chemotherapy. Participants received either full-dose S1 (Teysuno) or a dose-reduced S1 plus oxaliplatin. Blood samples were collected at baseline and biomarkers were dichotomized according to standard cut-offs. Multivariable analyses adjusted for age, sex, ECOG performance status, and treatment allocation; furthermore, C-statistics were estimated. In total, 160 patients with a median age of 78 years (IQR: 76−81) were included between 2015 and 2017. All investigated biomarkers were significantly elevated in patients with either weight loss, ≥3 metastatic sites, or primary tumor in situ. In multivariable analyses, all markers showed significant association with OS; the highest HR was observed for CRP (HR = 3.40, 95%CI: 2.20−5.26, p < 0.001). Regarding PFS, statistically significant differences were found for CRP and IL-6, but not for dNLR and YKL-40. Applying C-statistics, CRP indicated a good prognostic model for OS (AUC = 0.72, 95%CI: 0.67−0.76). CRP is an easily available biomarker, which may support therapeutic decision-making in vulnerable older patients with mCRC.

ctDNA for Risk of Recurrence Assessment in Patients Treated with Neoadjuvant Treatment: A Systematic Review and Meta-analysis

BACKGROUND

We wanted to investigate the association between circulating tumor DNA (ctDNA) detection at baseline, during and after neoadjuvant treatment, after surgery, and recurrence, in patients with nonmetastatic cancer.

PATIENTS AND METHODS

In this systematic review and meta-analysis, we included studies that investigated patients undergoing neoadjuvant treatment for nonmetastatic cancer and provided recurrence indices stratified for ctDNA status at the following timepoints: baseline, during treatment, posttreatment, and postsurgery. Study quality was reported with the Newcastle-Ottawa scale, REMARK checklist, and GRADE approach. PubMed, Embase, Cochrane Library, and Web of Science were our data sources (inception to 3 June 2021). The main outcome was risk of recurrence.

RESULTS

We identified ten studies including 727 patients with rectal, breast, gastric, and bladder cancer. All studies reported posttreatment ctDNA analysis, while seven, four, and six reported baseline, during treatment, and postsurgery ctDNA analysis, respectively. ctDNA detection was associated to recurrence across all timepoints [baseline: risk ratio (RR) 2.86, 95% confidence interval (CI) 1.33-6.14, during treatment: RR 3.81, 95% CI 2.09-6.92, posttreatment: RR 4.29, 95% CI 2.79-6.60, postsurgery: RR 8.03, 95% CI 3.16-20.43]. Heterogeneity was low to moderate.

CONCLUSIONS

This meta-analysis of observational studies found that ctDNA detection in patients undergoing neoadjuvant treatment for nonmetastatic cancer was associated with recurrence. A stronger association was evident in posttreatment and postsurgery timepoints. However, some studies reported low negative predictive value (NPV) of pathological complete response, showing that ctDNA-detection-guided escalation and de-escalation studies following neoadjuvant treatment regimens are needed before its role as a treatment guidance can be affirmed.

Abstract 3254: Multiomics detect potential mechanisms of resistance to BRAF targeted therapy in patients with BRAFV600E mutated solid tumors

Purpose: The purpose of this study was to identify mechanisms of resistance to BRAF targeted therapy using proteomics together with genomics and transcriptomics in patients with BRAFV600E mutated solid tumors.

Experimental procedures: A total of nine patients with BRAFV600E mutated advanced solid tumors (5 with colorectal cancer, 2 with neuroendocrine carcinoma, 1 with cholangiocarcinoma and 1 with breast cancer) treated with BRAF targeted therapy (BRAF inhibitor in combination with either MEK inhibitor and/or EGRF antibody) as part of the Copenhagen Prospective Personalized Oncology study, were included in this study. Tumor biopsies at baseline and at disease progression were analyzed with whole exome/genome sequencing (WES/WGS), transcriptomics (RNA sequencing) and proteomics. Genomic variants were analyzed together with changes in protein expression. Three filtering steps were used to identify potential resistance mechanisms from the proteomics measurements. Proteins were filtered for 1) proteins with a high shift in abundance between baseline and progression 2) proteins with known associations to the patient’s primary cancer based on text-mining and 3) proteins in pathways where BRAF is also involved.

Results: Alterations conferring resistance were identified in 2 out of 9 patients when comparing data from WES/WGS and RNA sequencing at baseline and at disease progression (one patient with PTBP2-BRAF fusion and one with NRAS mutation). Genomic or transcriptomic alterations conferring resistance were not detected in the remaining 7 patients. Notably, there was not a single protein shared between all 9 patients after our filtering, but when comparing overlap on pathway level, six pathways related to RAF and MAPK signaling were affected in all 9 patients. Particularly, paradoxical activation of RAF signaling seems to be an interesting candidate to explain resistance, where formation of RAF dimer structures happens as a response to treatment with BRAF inhibitors, selectively inhibiting BRAF monomer structures (i.e. BRAFV600E).

Conclusion: With a multiomic approach using proteomics together with genomics and transcriptomics, potential mechanisms of resistance were detected in all patients at disease progression, where resistance to BRAF targeted therapies had occurred. Six mechanisms of resistance were shared independently of diagnosis and BRAF inhibitor combination regimes. The potential of integrating proteomics with genomics and transcriptomics is promising and may potentially guide therapy for future patients with treatment resistant BRAFV600E mutated solid tumors.

Citation Format: Martina Eriksen, Annelaura Bach Nielsen, Filip Mundt, Josephine Kerzel Duel, Matthias Mann, Ulrik Lassen, Christina Westmose Yde, Camilla Qvortrup, Martin Højgaard, Iben Spanggaard, Kristoffer Staal Rohrberg. Multiomics detect potential mechanisms of resistance to BRAF targeted therapy in patients with BRAFV600E mutated solid tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3254.

Oxaliplatin Neuropathy: Predictive Values of Skin Biopsy, QST and Berve Conduction

BACKGROUND

Oxaliplatin-induced peripheral neuropathy negatively affects the quality of life for patients with gastrointestinal cancers and may cause neuropathic pain. Measures of peripheral nerve structure or function, such as intraepidermal nerve fiber density (IENFD) during treatment could reduce neuropathy severity through individualized dose reduction.

OBJECTIVE

The aim was to evaluate the predictive values of IENFD, quantitative sensory testing (QST), and nerve conduction studies (NCS) for significant neuropathy and neuropathic pain.

METHODS

Fifty-five patients were examined prospectively before, during, and six months following treatment using skin biopsies, QST and NCS. Clinically significant neuropathy six months after treatment was defined as reduced Total Neuropathy Score of more than five and neuropathic pain was assessed according to International Association for the Study of Pain criteria.

RESULTS

Thirty patients had a clinically significant neuropathy, and 14 had neuropathic pain. Vibration detection threshold (VDT) before treatment was correlated with clinically significant neuropathy six months after treatment (OR 0.54, p = 0.01) and reductions in cold detection threshold (CDT) after 25% of treatment (OR 1.38, p = 0.04) and heat pain threshold (HPT) after 50% of treatment (OR 1.91, p = 0.03) with neuropathic pain. Cut off values of 5 for baseline VDT and changes of more than -0.05 °C and -0.85 °C in CDT and HPT were estimated. Sensitivity and specificity was low to moderate. There was no correlation between changes in IENFD or NCS and significant neuropathy or neuropathic pain.

CONCLUSIONS

Vibration detection thresholds and thermal detection thresholds may be useful for prediction of clinically significant and painful neuropathy, respectively. However, low to moderate sensitivity and specificity may limit the predictive value in clinical practice.

[Phenotype- or genotype test for dihydropyrimidin dehydrogenase deficiency before treatment with a fluoropyrimidine]

Some patients may have partial or complete deficiency of dihydropyrimidin dehydrogenase (DPD) and be more likely to experience severe toxicity with 5-fluorouracil. Since the spring of 2020, the Danish Medicines Agency has recommended genotype or phenotype testing before treatment with a fluoropyrimidine, but the most appropriate test strategy is debated. In this review, we present polymorphisms in the genes coding for DPD and summarise the evidence for DPD-enzyme deficiency testing and pharmacokinetic guided dosing.

[Anti-vascular endothelian growth factor therapy in the field of oncology]

Through many years the ability to suppress angiogenesis has been exploited in the field of oncology. The efficiency is well-documented and the indications are constantly growing, although the impact often is rather limited, as we argue in this review. Recent evidence suggests that inhibition of angiogenesis may be clinically meaningful through several lines of treatment but lack of biomarkers limits an individualised approach. The tumour microenvironment is anti-immune and a combination of anti-angiogenic drugs and immunotherapy has demonstrated impressive results and may alter the therapy in the years to come.

Effects of high-intensity exercise training on physical fitness, quality of life and treatment outcomes after oesophagectomy for cancer of the gastro-oesophageal junction: PRESET pilot study

Background

Treatment for cancer of the gastro‐oesophageal junction (GOJ) can result in considerable and persistent impairment of physical fitness and health‐related quality of life (HRQoL). This controlled follow‐up study investigated the feasibility and safety of postoperative exercise training.

Methods

Patients with stage I–III GOJ cancer were allocated to 12 weeks of postoperative concurrent aerobic and resistance training (exercise group) or usual care (control group). Changes in cardiorespiratory fitness, muscle strength and HRQoL were evaluated. Adherence to adjuvant chemotherapy, hospitalizations and 1‐year overall survival were recorded to assess safety.

Results

Some 49 patients were studied. The exercise group attended a mean of 69 per cent of all prescribed sessions. After exercise, muscle strength and cardiorespiratory fitness were increased and returned to pretreatment levels. At 1‐year follow‐up, the exercise group had improved HRQoL (+13·5 points, 95 per cent c.i. 2·2 to 24·9), with no change in the control group (+3·7 points, −5·9 to 13·4), but there was no difference between the groups at this time point (+9·8 points, −5·1 to 24·8). Exercise was safe, with no differences in patients receiving adjuvant chemotherapy (14 of 16 versus 16 of 19; relative risk (RR) 1·04, 95 per cent c.i. 0·74 to 1·44), relative dose intensity of adjuvant chemotherapy (mean 57 versus 63 per cent; P = 0·479), hospitalization (7 of 19 versus 6 of 23; RR 1·41, 0·57 to 3·49) or 1‐year overall survival (80 versus 79 per cent; P = 0·839) for exercise and usual care respectively.

Conclusion

Exercise in the postoperative period is safe and may have the potential to improve physical fitness in patients with GOJ cancer. No differences in prognostic endpoints or HRQoL were observed. Registration number: NCT02722785 ( https://www.clinicaltrials.gov).

Metastatic colorectal carcinomas with high SATB2 expression are associated with better prognosis and response to chemotherapy: a population-based Scandinavian study

Background: Survival and response to therapy in patients with metastatic colorectal cancer (mCRC) are very heterogeneous. There is an unmet need for better markers of prognosis and treatment benefit for mCRC patients. The homeobox 2 gene SATB2 has a highly specific expression in colorectal tissue and is associated with better prognosis in non-metastatic CRC.Material and methods: A population-based cohort of 798 mCRC patients was analysed. From primary tumour material, protein expression was assessed by immunohistochemistry. BRAF and KRAS mutation status was also determined. Associations with clinicopathological data, overall and progression-free survival and response to first-line chemotherapy were analysed.Results: Tumour tissue and clinical data were available from 467 patients. SATB2 was strongly expressed in 58% of cases, significantly more in left-sided, low-grade and wild-type BRAF tumours. Patients with high SATB2 tumours had longer overall survival compared with low SATB2 tumours (median 13 vs 8 months respectively, p < .001). Chemotherapy was given to 282 patients (63%). Patients with high SATB2 tumours had longer OS (median 22 vs 15 months respectively, p = .001) and more often responded to chemotherapy than those with low SATB2 (objective response 43% vs 29%, p = .02; clinical response 83% vs 67%, p = .004). Progression-free survival on first-line irinotecan chemotherapy was longer in high SATB2 cases (median 8 vs 4 months respectively, p = .019). Patients with both low SATB2 expression and mutated BRAF (n = 69) had particularly poor survival compared to the rest (median 8 and 12 months respectively, p = .001). In multivariable analysis, the SATB2 findings were independent of known clinicopathological prognostic markers, including BRAF mutation status.Conclusion: Patients with mCRC expressing high level of SATB2 have better prognosis and response to chemotherapy than those with low SATB2 expression. Patients with both low SATB2 expression and mutated BRAF had particularly poor prognosis and could thus benefit from more aggressive therapies.

TAS-102 with or without bevacizumab in patients with chemorefractory metastatic colorectal cancer: an investigator-initiated, open-label, randomised, phase 2 trial

BACKGROUND

TAS-102 (trifluridine-tipiracil) has shown a significant overall survival benefit compared with placebo in patients with chemorefractory metastatic colorectal cancer. Inspired by the encouraging results of a small phase 1-2 study, C-TASK FORCE, which evaluated the combination of TAS-102 plus bevacizumab in patients with chemorefractory metastatic colorectal cancer, we aimed to compare the efficacy of TAS-102 plus bevacizumab versus TAS-102 monotherapy in patients receiving refractory therapy for metastatic colorectal cancer .

METHODS

This investigator-initiated, open-label, randomised, phase 2 study enrolled patients (aged ≥18 years) with metastatic colorectal from four cancer centres in Denmark. The main inclusion criteria were histopathologically confirmed metastatic colorectal cancer refractory or intolerant to a fluoropyrimidine, irinotecan, oxaliplatin, and cetuximab or panitumumab (only for RAS wild-type), and WHO performance status of 0 or 1. Previous therapy with bevacizumab, aflibercept, ramucirumab, or regorafenib was allowed but not mandatory. Participants were enrolled and randomly assigned (1:1) in block sizes of two, four, or six by a web-based tool to receive oral TAS-102 (35 mg/m² twice daily on days 1-5 and 8-12 every 28 days) alone or combined with intravenous bevacizumab (5 mg/kg on days 1 and 15) until progression, unacceptable toxicity, or patient decision to withdraw. Treatment assignment was not masked, and randomisation was stratified by institution and RAS mutation status. The primary endpoint was investigator-evaluated progression-free survival. All analyses were based on intention to treat. This trial is registered with EudraCT, 2016-005241-23.

FINDINGS

From Aug 24, 2017, to Oct 31, 2018, 93 patients were enrolled and randomly assigned to TAS-102 (n=47) or TAS-102 plus bevacizumab (n=46). The clinical cut-off date was Feb 15, 2019, after a median follow-up of 10·0 months (IQR 6·8-14·0). Median progression-free survival was 2·6 months (95% CI 1·6-3·5) in the TAS-102 group versus 4·6 months (3·5-6·5) in the TAS-102 plus bevacizumab group (hazard ratio 0·45 [95% CI 0·29-0·72]; p=0·0015). The most frequent grade 3 or worse adverse event was neutropenia (18 [38%] of 47 in the TAS-102 monotherapy group vs 31 [67%] of 46 in the TAS-102 plus bevacizumab group). Serious adverse events were observed in 21 (45%) patients in the TAS-102 group and 19 (41%) in the TAS-102 plus bevacizumab group. No deaths were deemed treatment related.

INTERPRETATION

In patients with chemorefractory metastatic colorectal cancer, TAS-102 plus bevacizumab, as compared with TAS-102 monotherapy, was associated with a significant and clinically relevant improvement in progression-free survival with tolerable toxicity. The combination of TAS-102 plus bevacizumab could be a new treatment option for patients with refractory metastatic colorectal cancer and could be a practice-changing development.

FUNDING

Servier.

[Increasing incidence of colorectal cancer in young patients]

For the past decades, an increase in the incidence of colorectal cancer in young patients has been reported in several countries, including Denmark, and efforts need to be taken in order to halt this tendency. This review characterises the clinical and pathological attributes of young patients with early-onset colorectal cancer (EOCRC). Risk factors such as smoking and sedentary lifestyle have been found to be associated with EOCRC. Further studies are needed to evaluate, if the age of patients entering the Danish screening programme for bowel cancer should be lowered.

[Trends in oncological phase I trials]

This review summarises the current knowledge of anticancer therapy. More than 1,100 cancer drugs are currently under development in the United States. The increasing biological insight and platforms for high throughput screening of drugs have changed the developmental landscape of anticancer therapies from classical cytotoxic agents to targeted agents and immunotherapy. There is an increasing number of targeted agents, which are only efficacious in tumours harbouring specific genomic alterations in early clinical development. Furthermore, the landscape of immunotherapy broadens, and personalised immunotherapy is in development. The integration of genomic testing into early clinical oncology trials is increasing.

Early changes in tests of peripheral nerve function during oxaliplatin treatment and their correlation with chemotherapy-induced polyneuropathy symptoms and signs

BACKGROUND AND PURPOSE

Assessment of the severity of chronic peripheral neuropathy during oxaliplatin treatment is based on symptoms. Efforts to adjust the total dose of oxaliplatin to prevent severe neuropathy can be complicated by the worsening of neuropathy symptoms following treatment. Objective measures of the structure and function of peripheral nerves during early phases of treatment may aid in determining the optimal oxaliplatin dose in individual patients. Intraepidermal nerve fibre density (IENFD) has been suggested as an early marker of peripheral neuropathy.

METHODS

Sixty patients were examined before treatment and following 25% and 50% of the total planned oxaliplatin dose. Fifty-five of them were also examined at completion of chemotherapy and 6 months later. IENFD in skin biopsies from the distal leg, nerve conduction studies and quantitative sensory testing at the dorsum of the foot were performed. Forty-six healthy subjects were examined at baseline and after 6 and 52 weeks for comparison.

RESULTS

Intraepidermal nerve fibre density was not reduced during treatment. Sural nerve amplitude and conduction velocity, vibration detection thresholds, mechanical detection threshold and cold detection threshold were significantly reduced during treatment. Compared to reference values and spontaneous changes in healthy subjects, the largest proportions of patients with deterioration were found for vibration detection thresholds followed by nerve conduction studies, mechanical detection threshold, cold detection threshold and IENFD.

CONCLUSIONS

Significant changes were most pronounced for measures of large nerve fibre function, especially vibration sensation. Skin biopsies do not seem to provide a clinically relevant objective measure of peripheral nerve deterioration during oxaliplatin treatment.

The Global POLAR program: Two pivotal placebo-controlled studies of calmangafodipir used on top of modified FOLFOX6 to prevent chemotherapy-induced peripheral neuropathy (CIPN)

TPS3616

Background: Oxaliplatin (OXA), is approved in combination with 5-FU/FA (5-fluorouracil/folinic acid; FOLFOX) for metastatic as well as in adjuvant colo-rectal cancer (CRC) treatment. CIPN is a common adverse event, after OXA treatment. The incidence of chronic CIPN is approximately 15% after a cumulative dose of 780 to 850 mg/m² and 50% after a cumulative dose of 1170 mg/m². OXA induced neuropathy, results in greatly reduced nitrated manganese superoxide dismutase (MnSOD) activity. Treatment with a superoxide dismutase mimetic, such as calmangafodipir (CAL), prevents and reverses oxaliplatin-induced neuropathies. This has been demonstrated in the PLIANT study, with CAL (Glimelius et al. 2017). Methods: The POLAR program is a Phase 3, multicenter, placebo (PLC)-controlled program of CAL to prevent CIPN, recruiting in US, Europe (B, D, ES, F,ES, I and UK) and Asia (J, SK, TW and HK) and is described below; POLAR A Patients with CRC, treatment of patients with Stage III or high-risk Stage II who are indicated for adjuvant modified FOLFOX6 (mFOLFOX6) chemotherapy for up to 6 months, randomized in a 1:1 ratio, each arm n = 140: A: CAL (5 µmol/kg) + mFOLFOX6 chemotherapy B: PLC + mFOLFOX6 chemotherapy POLAR M Patients with metastatic colorectal cancer (mCRC), who are indicated for first-line mFOLFOX6 chemotherapy for at least 3 months, without any pre-planned treatment breaks and will be randomized in a 1:1:1 ratio, each arm n = 140: A: CAL (2 µmol/kg) + mFOLFOX6 chemotherapy B: CAL (5 µmol/kg) + mFOLFOX6 chemotherapy C: PLC + mFOLFOX6 chemotherapy Primary objective is to compare CAL vs PLC with respect to the proportion of patients with moderate or severe chronic CIPN. The primary endpoint is; Patient reported symptoms as proportion of patients scoring 3 or 4 in at least 1 of the first 4 items of the FACT/GOG-NTX-13 (i.e., FACT/GOG-NTX-4), targeting numbness, tingling or discomfort in hands and/or feet, assessed 9 months after the first dose of chemotherapy. In addition to conventional safety endpoints, Progressive Free Survival and Overall Survival are assessed in the POLAR M study. In the POLAR A study Disease Free Survival is one additional safety endpoint assessed. Results are expected during second half 2020. Clinical trial information: NCT03654729.

Reduced-dose combination chemotherapy (S-1 plus oxaliplatin) versus full-dose monotherapy (S-1) in older vulnerable patients with metastatic colorectal cancer (NORDIC9): a randomised, open-label phase 2 trial

BACKGROUND

Older or vulnerable patients with metastatic colorectal cancer are seldom included in randomised trials. The multicentre NORDIC9 trial evaluated reduced-dose combination chemotherapy compared with full-dose monotherapy in older, vulnerable patients.

METHODS

This randomised, open-label phase 2 trial was done in 23 Nordic oncology clinics and included patients aged 70 years or older with previously untreated metastatic colorectal cancer who were not candidates for full-dose combination chemotherapy. Patients were block randomised (1:1) using a web-based tool to full-dose S-1 (30 mg/m² orally twice daily on days 1-14 every 3 weeks) followed by second-line treatment at progression with irinotecan (250 mg/m² intravenously on day 1 every 3 weeks or 180 mg/m² intravenously on day 1 every 2 weeks) or reduced-dose combination chemotherapy with S-1 (20 mg/m² orally twice daily on days 1-14) and oxaliplatin (100 mg/m² intravenously on day 1 every 3 weeks) followed by second-line treatment at progression with S-1 (20 mg/m² orally twice daily on days 1-14) and irinotecan (180 mg/m² intravenously on day 1 every 3 weeks). Use of bevacizumab (7·5 mg/kg intravenously on day 1 of each cycle) was optional. Treatment allocation was not masked and randomisation was stratified for institution and bevacizumab. The primary outcome was progression-free survival. Survival analyses were by intention to treat and safety analyses were done on the treated population. This trial is registered with EudraCT, number 2014-000394-39, and is closed to new participants.

FINDINGS

From March 9, 2015, to Oct 11, 2017, 160 patients with a median age of 78 years (IQR 76-81) were randomly assigned to full-dose monotherapy (n=83) or reduced-dose combination chemotherapy (n=77). At data cutoff (Sept 1, 2018; median follow-up 23·8 months [IQR 18·8-30·9]), 81 (98%) patients in the full-dose monotherapy group and 71 (92%) patients in the reduced-dose combination group had progressed or died. Median progression-free survival was significantly longer with reduced-dose combination chemotherapy (6·2 months [95% CI 5·3-8·3]) than with full-dose monotherapy (5·3 months [4·1-6·8]; hazard ratio [HR] 0·72 [95% CI 0·52-0·99]; p=0·047). Toxicity was evaluated in 157 patients who received treatment. Significantly more patients in the full-dose monotherapy group (51 [62%] of 82 patients) experienced at least one grade 3-4 adverse event than in the reduced-dose combination group (32 [43%] of 75 patients; p=0·014). Grade 3-4 diarrhoea (12 [15%] vs two [3%]; p=0·018), fatigue (ten [12%] vs three [4%]; p=0·083), and dehydration (five [6%] vs none; p=0·060) were more frequent in the full-dose monotherapy group than in the reduced-dose combination group. Treatment-related deaths occurred in three patients during first-line treatment and three patients during second-line treatment (two in the full-dose monotherapy group vs one in the reduced-dose combination group in both cases).

INTERPRETATION

Reduced-dose combination chemotherapy with S-1 and oxaliplatin for older, vulnerable patients with metastatic colorectal cancer was more effective and resulted in less toxicity than full-dose monotherapy with S-1. Reduced-dose combination chemotherapy could be a preferred treatment for this population.

FUNDING

Taiho Pharmaceuticals, Nordic Group, the Danish Cancer Society, the Swedish Cancer Society, Academy of Geriatric Research (AgeCare), and Region of Southern Denmark.