A randomized phase III trial of adjuvant chemotherapy with irinotecan, leucovorin and fluorouracil versus leucovorin and fluorouracil for stage II and III colon cancer: a Hellenic Cooperative Oncology Group study

Polycaprolactone/β-Tricalcium Phosphate Composite Scaffolds with Advanced Pore Geometries Promote Human Mesenchymal Stromal Cells' Osteogenic Differentiation

Critical-sized mandibular bone defects, arising from, for example, resections after tumor surgeries, are currently treated with autogenous bone grafts. This treatment is considered very invasive and is associated with limitations such as morbidity and graft resorption. Tissue engineering approaches propose to use 3D scaffolds that combine structural features, biomaterial properties, cells, and biomolecules to create biomimetic constructs. However, mimicking the complex anatomy and composition of the mandible poses a challenge in scaffold design. In our study, we evaluated the dual effect of complex pore geometry and material composition on the osteogenic potential of 3D printed scaffolds. The scaffolds were made of polycaprolactone (PCL) alone (TCP0), or with a high concentration of β-tricalcium phosphate (β-TCP) up to 40% w/w (TCP40), with two complex pore geometries, namely a star- (S) and a diamond-like (D) shape. Scanning electron microscopy and microcomputed tomography images confirmed high fidelity during the printing process. The D-scaffolds displayed higher compressive moduli than the corresponding S-scaffolds. TCP40 scaffolds in simulated body fluid showed deposition of minerals on the surface after 28 days. Subsequently, we assessed the differentiation of seeded bone marrow-derived human mesenchymal stromal cells (hMSCs) over 28 days. The early expression of RUNX2 in the cell nuclei confirmed the commitment toward an osteogenic phenotype. Moreover, alkaline phosphatase (ALP) activity and collagen deposition displayed an increasing trend in the D-scaffolds. Collagen type I was mainly present in the deposited extracellular matrix (ECM), confirming deposition of bone matrix. Finally, Alizarin Red staining showed successful mineralization on all the TCP40 samples, with higher values for the S-shaped scaffolds. Taken together, our study demonstrated that the complex pore architectures of scaffolds comprised TCP40 stimulated osteogenic differentiation and mineralization of hMSCs in vitro. Future research will aim to validate these findings in vivo.

Nanoparticle and Nanotopography-Induced Activation of the Wnt Pathway in Bone Regeneration

Background and Aims: Recent research has focused on developing nanoparticle and nanotopography-based technologies for bone regeneration. The Wingless-related integration site (Wnt) signaling pathway has been shown to play a vital role in this process, in particular in osteogenic differentiation and proliferation. The exact mechanisms by which nanoparticles and nanotopographies activate the Wnt signaling pathway, however, are not fully understood. This review aimed to elucidate the mechanisms by which nanoscale technologies activate the Wnt signaling pathway during bone regeneration. Methods: The terms "Wnt," "bone," and "nano*" were searched on PubMed and Ovid with no date limit. Only original research articles related to Wnt signaling and bone regeneration in the context of nanotopographies, nanoparticles, or scaffolds with nanotopographies/nanoparticles were reviewed. Results: The primary mechanism by which nanoparticles activated the Wnt pathway was by internalization through the endocytic pathway or diffusion through the cell membrane, leading to accumulation of nonphosphorylated β-catenin in the cytoplasm and subsequently downstream osteogenic signaling (e.g., upregulation of runt-related transcription factor 2 [RUNX2]). The specific size of the nanoparticles and the process of endocytosis itself has been shown to modulate the Wnt-β-catenin pathway. Nanotopographies were shown to directly activate frizzled receptors, initiating Wnt/β-catenin signaling. Additional studies showed nanotopographies to activate the Wnt/calcium (Wnt/Ca2+)-dependent and Wnt/planar cell polarity pathways through nuclear factor of activated T cells, and α5β1 integrin stimulation. Finally, scaffolds containing nanotopographies/nanoparticles were found to induce Wnt signaling through a combination of ion release (e.g., lithium, boron, lanthanum, and icariin), which inhibited glycogen synthase kinase 3 beta (GSK-3β) activity, and through similar mechanisms to the nanotopographies. Conclusion: This review concludes that nanoparticles and nanotopographies cause Wnt activation through several different mechanisms, specific to the size, shape, and structure of the nanoparticles or nanotopographies. Endocytosis-related mechanisms, integrin signaling and ion release were the major mechanisms identified across nanoparticles, nanotopographies, and scaffolds, respectively. Knowledge of these mechanisms will help develop more effective targeted nanoscale technologies for bone regeneration. Impact statement Nanoparticles and nanotopographies can activate the Wingless-related integration site (Wnt) signaling pathway, which is essential for bone regeneration. This review has identified that activation is due to endocytosis, integrin signaling and ion release, depending on the size, shape, and structure of the nanoparticles or nanotopographies. By identifying and further understanding these mechanisms, more effective nanoscale technologies that target the Wnt signaling pathway can be developed. These technologies can be used for the treatment of nonunion bone fractures, a major clinical challenge, with the potential to improve the quality of life of millions of patients around the world.

Postoperative Chemotherapy After Surgical Resection of Metachronous Metastases of Colorectal Cancer: A Systematic Review

Currently, 6 months of perioperative or adjuvant chemotherapy (ACT) is a standard treatment option after radical surgical removal of metachronous metastases in patients with metastatic colorectal cancer (CRC). Data show that ACT improves relapse-free survival in such patients, although no difference in overall survival rate was observed. We perform a systematic review to evaluate the efficacy of adjuvant chemotherapy after radical resection of metachronous metastases in CRC.

The Efficacy of Using Patient-Derived Organoids to Predict Treatment Response in Colorectal Cancer

Colorectal cancer is an important cause of morbidity and mortality worldwide. The current treatment landscape includes chemotherapy, targeted therapy, immunotherapy, radiotherapy, and surgery. A key challenge to improving patient outcomes is the significant inter-patient heterogeneity in treatment response. Tumour organoids derived from the patients' tumours via surgically resected or endoscopically biopsied tissue, have emerged as promising models for personalised medicine. This review synthesises the findings, to date, of studies which have explored the efficacy of ex vivo organoid sensitivity testing for predicting treatment response. Most studies have focused on predicting the response to standard-of-care radiotherapy and chemotherapy options. There is strong evidence to support organoid sensitivity testing of ionising radiation, 5-fluorouracil, and irinotecan, and to a lesser extent, oxaliplatin and TAS-102. Fewer studies have used organoids to identify patients who are likely to benefit from novel treatment options that otherwise remain in clinical trials. This review also summarises recent advancements in organoid culture to include non-epithelial components of the tumour microenvironment, to allow testing of immunotherapy and certain targeted therapy options. Overall, further prospective trials will support the implementation of organoid-based personalised medicine for colorectal cancer patients in the future.

Clinical and Biological Aspects of Disseminated Tumor Cells and Dormancy in Breast Cancer

Progress in detection and treatment have drastically improved survival for early breast cancer patients. However, distant recurrence causes high mortality and is typically considered incurable. Cancer dissemination occurs via circulating tumor cells (CTCs) and up to 75% of breast cancer patients could harbor micrometastatses at time of diagnosis, while metastatic recurrence often occurs years to decades after treatment. During clinical latency, disseminated tumor cells (DTCs) can enter a state of cell cycle arrest or dormancy at distant sites, and are likely shielded from immune detection and treatment. While this is a challenge, it can also be seen as an outstanding opportunity to target dormant DTCs on time, before their transformation into lethal macrometastatic lesions. Here, we review and discuss progress made in our understanding of DTC and dormancy biology in breast cancer. Strides in our mechanistic insights of these features has led to the identification of possible targeting strategies, yet, their integration into clinical trial design is still uncertain. Incorporating minimally invasive liquid biopsies and rationally designed adjuvant therapies, targeting both proliferating and dormant tumor cells, may help to address current challenges and improve precision cancer care.

Serious Adverse Events Reporting in Phase III Randomized Clinical Trials of Colorectal Cancer Treatments: A Systematic Analysis

Objective: The occurrence, development, and prognosis of serious adverse events (SAEs) associated with anticancer drugs in clinical trials have important guiding significance for real-world clinical applications. However, to date, there have been no studies investigating SAEs reporting in randomized clinical trials of colorectal cancer treatments. This article systematically reviewed the SAEs reporting of phase III randomized clinical trials of colorectal cancer treatments and analyzed the influencing factors. Methods: We reviewed all articles about phase III randomized clinical trials of colorectal cancer treatments published in the PubMed, Embase, Medline, and New England Journal of Medicine databases from January 1, 1993, to December 31, 2018, and searched the registration information of clinical trials via the internet sites such as "clinicaltrials.gov". We analyzed the correlation between the reported proportion (RP) of SAEs in the literature and nine elements, including the clinical trial sponsor and the publication time. Chi-square tests and binary logistic regression were used to identify the factors associated with improved SAEs reports. This study was registered on PROSPERO. Results: Of 1560 articles identified, 160 were eligible, with an RP of SAEs of 25.5% (41/160). In forty-one publications reporting SAEs, only 14.6% (6/41) described the pattern of SAEs in detail. In clinical trials sponsored by pharmaceutical companies, the RP of SAEs was significantly higher than that in those sponsored by investigators (57.6 versus 20.7%, p < 0.001). From 1993 to 2018, the RP of SAEs gradually increased (none (0/6) before 2000, 17.1% (12/70) from 2000 to 2009, and 34.5% (29/84) after 2009). The average RP of SAEs published in the New England Journal of Medicine (N Engl J Med), the Lancet, the Journal of the American Medical Association (JAMA), the Lancet Oncology (Lancet Oncol), and the Journal of Clinical Oncology (J Clin Oncol) was significantly higher than that published in other journals (31.9 versus 16.7%, p = 0.030). In the clinical trials referenced by clinical guidelines, the RP of SAEs was higher than that in non-referenced clinical trials (32.0 versus 15.9%, p = 0.023). Binary logistic regression analysis showed that pharmaceutical company sponsorship, new drug research, and sample size greater than 1000 were positive influencing factors for SAEs reporting. Conclusion: Although the RP of SAEs increased over time, SAEs reporting in clinical trials needs to be further improved. The performance, outcomes and prognosis of SAEs should be reported in detail to guide clinical practice in the real world.

Adjuvant Chemotherapy for Stage II Colon Cancer

Simple Summary

Stage II colon cancer is defined as an early stage of the tumor disease, without the involvement of lymph nodes or distant organs. In this group of patients, surgery alone is associated with high cure rate and the role of post-operative chemotherapy is still a matter of debate. In patients with tumor features associated with a high risk of recurrence, post-operative chemotherapy is recommended even if it has a small survival benefit. This clinical issue leads to the need for identifying patients who may benefit from post-operative chemotherapy based on their risk of recurrence. The purpose of this review is to highlight and discuss the uncertainties of the previous trials about the risk stratification, the weight of each prognostic factor and the therapeutic benefit of adjuvant chemotherapy in stage II colon cancer patients. Moreover, we summarize the data from previous studies in a decision algorithm that could help clinicians in clinical practice.

Abstract

In stage II colon cancer management, surgery alone has shown a high cure rate (about 80%), and the role of adjuvant chemotherapy is still a matter of debate. Patients with high-risk features (T4, insufficient nodal sampling, grading, etc.) have a poorer prognosis and, usually, adjuvant chemotherapy is recommended. The purpose of the present study is to highlight and discuss what is still unclear and not completely defined from the previous trials regarding risk stratification and therapeutic benefit of adjuvant chemotherapy. With all the limitations of generalizing, we make the effort of trying to quantify the relative contribution of each prognostic factor and the benefit of adjuvant chemotherapy for stage II colon cancer. Finally, we propose a decision algorithm with the aim of summarizing the current evidence and translating it to clinical practice.

Comparison of Drugs Used for Adjuvant and Metastatic Therapy of Colon, Breast, and Non-Small Cell Lung Cancers

IMPORTANCE

Drugs are used in the adjuvant, metastatic, or both settings in cancer, but the rate, direction, and speed with which drugs are tested and indicated in each setting are unknown.

OBJECTIVE

To identify the number of unique agents that are currently category 1 or 2A per National Comprehensive Cancer Network (NCCN) guidelines in metastatic and adjuvant settings of non-small cell lung cancer (NSCLC), breast cancer, and colon cancer, as well as the mean delay between use in these 2 settings and the quality of supporting evidence.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study used NCCN treatment guidelines current as of May 15, 2019, and the clinical trials cited either by these guidelines or within corresponding drug labels. Trials published between 1970 and 2019 were evaluated. The analysis included published clinical trials of systemic therapy options deemed by the NCCN as category 1 or 2A. Participants included patients with early or metastatic NSCLC, breast cancer, or colon cancer who were included in clinical trials evaluating current NCCN-recommended systemic therapy options. Data analysis was performed from March 2019 to May 2019.

EXPOSURES

Systemic therapy regimens used as either adjuvant treatment or as therapy for metastatic disease in the 3 cancer types.

MAIN OUTCOMES AND MEASURES

Number of agents recommended for use in adjuvant and metastatic settings of NSCLC, colon cancer, and breast cancer, the mean delay between use in these 2 settings, and the percentage of agents supported by trials with substantial improvement in either progression-free survival (disease-free survival for adjuvant agents) or overall survival.

RESULTS

This study identified 69 agents recommended for use in metastatic disease compared with 25 agents recommended for adjuvant use. For agents used in both settings, the mean (SD) delay between use in metastatic disease and as adjuvant therapy was 10.0 (7.5) years. On the basis of trials with positive outcomes, 39 of 69 agents (56.5%) were approved or recommended in the metastatic setting, compared with 23 of 25 agents (92.0%) approved for use as adjuvant therapy.

CONCLUSIONS AND RELEVANCE

There is a substantial difference in the number of agents available for use, as well as the timing of supporting evidence, in the metastatic and adjuvant settings for NSCLC, breast cancer, and colon cancer. Given the potential benefit of adjuvant therapy in these cancer types, further investigation into additional adjuvant systemic therapy options is warranted.

Guidelines for time-to-event end-point definitions in adjuvant randomised trials for patients with localised colon cancer: Results of the DATECAN initiative

BACKGROUND

The variability of definitions for time-to-event (TTE) end-points impacts the conclusions of randomised clinical trials (RCTs). The Definition for the Assessment of Time-to-event Endpoints in CANcer (DATECAN) initiative aims to provide consensus definitions for TTE end-points used in RCTs. Here, we formulate guidelines for adjuvant colon cancer RCTs.

METHODS

We performed a literature review to identify TTE end-points and events included in their definition in RCT publications. Then, a consensus was reached among a panel of international experts, using a formal modified Delphi method, with 2 rounds of questionnaires and an in-person meeting.

RESULTS

Twenty-four experts scored 72 events involved in 6 TTE end-points. Consensus was reached for 24%, 57% and 100% events after the first round, second round and in-person meeting. For RCTs not using overall survival as their primary end-point, the experts recommend using disease-free survival (DFS) rather than recurrence-free survival (RFS) or time to recurrence (TTR) as the primary end-point. The consensus definition of DFS includes all causes of death, second primary colorectal cancers (CRCs), anastomotic relapse and metastatic relapse as an event, but not second primary non-CRCs. Events included in the RFS definition are the same as for DFS with the exception of second primary CRCs. The consensus definition of TTR includes anastomotic or metastatic relapse, death with evidence of recurrence and death from CC cause.

CONCLUSION

Standardised definitions of TTE end-points ensure the reproducibility of the end-points between RCTs and facilitate cross-trial comparisons. These definitions should be integrated in standard practice for the design, reporting and interpretation of adjuvant CC RCTs.

DNA-mediated biomineralization of calcium-deficient hydroxyapatite for bone tissue engineering

A random DNA duplex was utilized as the biotemplate to mediate the biomineralization of calcium-deficient hydroxyapatite with osteoconductive properties.

Making sense of adjuvant chemotherapy in colorectal cancer

Surgical resection is the only curative treatment for locoregional colon cancer. The goal of adjuvant chemotherapy is to eradicate micro-metastatic disease and improve survival. This has been most clearly demonstrated in stage III (node-positive) disease, whereas benefit of adjuvant chemotherapy in stage II disease remains controversial. In stage III colon cancer, 6 months of adjuvant chemotherapy with oxaliplatin-based chemotherapy have been accepted as the standard for the last 15 years. The recent IDEA collaboration has challenged this in 2018; while overall was a negative non-inferiority study, pre-planned subset analyses do support that for patients with low-risk stage III disease, 3 months of XELOX (capecitabine and oxaliplatin combination) is non-inferior to 6 months. In stage II colon cancer, where the potential benefit of adjuvant chemotherapy is small, the emergence of biomarkers has helped in decision-making. Tumors with deficient mismatch repair protein (dMMR) do not benefit from 5-fluorouracil-based chemotherapy. For patients with high clinicopathological risk stage II disease with proficient mismatch repair proteins and good performance status, six months of adjuvant chemotherapy is still recommended. In the management of rectal cancers, where the risk of local recurrence is higher, chemoradiation (CRT) is often included as neoadjuvant or adjuvant therapy in the management of stage II and III rectal cancer. The benefit of adjuvant chemotherapy in rectal cancer has been extrapolated from adjuvant colon cancer studies with updated results from adjuvant rectal cancer studies demonstrating similar benefits. This review summarizes the current landscape of adjuvant therapy for patients with resected stage II and III colorectal cancer.

Current Treatment Strategies for Elderly Patients with Metastatic Colon Cancer

Colon cancer is one of the most common cancers in the United States and is expected to rise as the prevalence of colon cancer is increasing with increasing aging population. Though some studies have shown benefits of chemotherapy in the elderly population, however, they are also at risk of drug toxicities. We searched major search engines including PubMed, Medline and EMBASE and reviewed articles published in the last 10 years. Here we present current treatment strategies available for the metastatic colon cancer in elderly patients.

Adjuvant Chemotherapy of Locally Advanced Colon Cancer: Final Results of a Randomized Trial Comparing 5-Fluorouracil and Folinic Acid with Folfiri

BACKGROUND

There is still the need to optimize adjuvant treatment of colon cancer (CC). Standard adjuvant chemotherapy using 5-fluorouracil (FU) and folinic acid (FA) was compared with a combination including irinotecan (Folfiri). The aim of the present report was to analyze overall survival (OS) after long-term follow-up, to summarize final recurrence rates and toxicity data, and to identify possible clinical and pathological factors associated with prognosis.

METHODS

Patients (CC stage IIb and III) were randomized to a 6-month treatment with FUFA or Folfiri. The trial was closed after 275 of 588 planned patients, 269 of which were included in the intention-to-treat analysis.

RESULTS

133 and 136 patients received FUFA and Folfiri, respectively. Adjuvant therapy was not completed for 16 FUFA (12.0%) and 44 Folfiri (32.4%) patients. Toxicities grade III and IV were observed in 17 (12.8%) patients treated with FUFA and in 50 (36.8%) patients treated with Folfiri. Recurrences occurred in 46 of 133 (34.6%) and in 47 of 136 (34.6%) patients who received FUFA and Folfiri, respectively. 5-year OS rates were 69.9% (95% confidence interval (CI): 61.2-77.1) for FUFA and 72.7% (95% CI: 63.9-79.8) for Folfiri. OS was associated with tumor grading (1 & 2 vs. 3), tumor sub-stage (II vs. IIIa vs. IIIb vs. IIIc), and tumor location (left vs. right colon).

CONCLUSION

Folfiri cannot be generally recommended for adjuvant chemotherapy of CC. Besides tumor grading and sub-staging, prognosis of CC may depend on tumor location. Left-sided tumors had a significantly better prognosis irrespective of treatment.

Combination adjuvant chemotherapy with targeted drugs for treatment of colorectal cancer: A network meta-analysis

Colorectal cancer (CRC) is one of the most fatal diseases in the world. The efficacy of present chemotherapy treatments are limited and the addition of targeted drugs have been put into practice. However, the preferred treatments among adjuvant chemotherapies still remain controversial and uncertain. To evaluate the efficacy of different adjuvant chemotherapies combined with or without targeted drugs to determine the optimal treatment for patients with CRC in clinical practice. PubMed and Embase were searched for eligible articles and only randomized controlled trials (RCTs) were included. R (Version 3.2.5) software was utilized to conduct the Bayesian network meta-analysis (NMA). Outcomes including overall survival (OS) and progression-free survival (PFS) were displayed using hazard ratios. And the rank probabilities of each treatment were evaluated using the surface under cumulative ranking curve. A total of 75 RCTs published after 1997 were included in the data analysis. Overall, FOLFIRI+ cetuximab was found to be the most effective treatment in terms of long-term survival and FOLFOX was the most effective pure chemotherapy treatment. The addition of targeted drugs will greatly improve the efficacy of chemotherapy. Targeted drug cetuximab combined with the chemotherapy regiment FOLFIRI is the preferable treatment for patients with CRC in clinical practice.

Comprehensive Analysis of miRNome Alterations in Response to Sorafenib Treatment in Colorectal Cancer Cells

MicroRNAs (miRNAs) are master regulators of drug resistance and have been previously proposed as potential biomarkers for the prediction of therapeutic response in colorectal cancer (CRC). Sorafenib, a multi-kinase inhibitor which has been approved for the treatment of liver, renal and thyroid cancer, is currently being studied as a monotherapy in selected molecular subtypes or in combination with other drugs in metastatic CRC. In this study, we explored sorafenib-induced cellular effects in Kirsten rat sarcoma viral oncogene homolog olog (KRAS) wild-type and KRAS-mutated CRC cell lines (Caco-2 and HRT-18), and finally profiled expression changes of specific miRNAs within the miRNome (>1000 human miRNAs) after exposure to sorafenib. Overall, sorafenib induced a time- and dose-dependent growth-inhibitory effect through S-phase cell cycle arrest in KRAS wild-type and KRAS-mutated CRC cells. In HRT-18 cells, two human miRNAs (hsa-miR-597 and hsa-miR-720) and two small RNAs (SNORD 13 and hsa-miR-3182) were identified as specifically sorafenib-induced. In Caco-2 cells, nine human miRNAs (hsa-miR-3142, hsa-miR-20a, hsa-miR-4301, hsa-miR-1290, hsa-miR-4286, hsa-miR-3182, hsa-miR-3142, hsa-miR-1246 and hsa-miR-720) were identified to be differentially regulated post sorafenib treatment. In conclusion, we confirmed sorafenib as a potential anti-neoplastic treatment strategy for CRC cells by demonstrating a growth-inhibitory and cell cycle–arresting effect of this drug. Changes in the miRNome indicate that some specific miRNAs might be relevant as indicators for sorafenib response, drug resistance and potential targets for combinatorial miRNA-based drug strategies.

Impact of Dose Reductions, Delays Between Chemotherapy Cycles, and/or Shorter Courses of Adjuvant Chemotherapy in Stage II and III Colorectal Cancer Patients: a Single-Center Retrospective Study

PURPOSE

Most stage II or III colorectal cancer patients are receiving nowadays a 4 to 6-month course of adjuvant chemotherapy. However, delays between cycles, reductions in the doses of chemotherapy drugs, or even permanent omissions of chemotherapy cycles might take place due to side effects or patient's preference. We examined the impact of these treatment modifications on recurrence-free survival (RFS) and overall survival (OS).

METHODS

We retrospectively collected data from colorectal cancer patients who had received adjuvant chemotherapy in our Department. Patients were categorized in five groups based on whether they had or not delays between chemotherapy cycles, dose reductions, and permanent omissions of chemotherapy cycles. Three-year RFS and OS of the five different groups were compared using the log-rank test and the Sidak approach.

RESULTS

Five hundred and eight patients received treatment. Twenty seven percent of the patients had the full course of chemotherapy; the others had delays, dose reductions, or early termination of the treatment. No statistically significant differences were observed in 3-year RFS and OS between the five groups. A trend for worse RFS was noticed with early termination of treatment. A similar trend was also noticed for OS but only for stage II patients.

CONCLUSION

In colorectal cancer patients, receiving adjuvant chemotherapy, delays between chemotherapy cycles, dose reductions of chemotherapy drugs, or even early termination of the treatment course do not seem to have a negative impact in 3-year RFS and OS; however, due to the trend of worse RFS in patients receiving shorter courses of chemotherapy, further studies are needed.

Stage III Colon Cancer: What Works, What Doesn't and Why, and What's Next

Adjuvant treatment for patients with stage III colon cancer, one of the most common malignancies, is an important issue in oncology. The use of adjuvant chemotherapy in this setting has undoubtedly improved prognosis. This article describes the development of adjuvant therapy and progress in the past decade as well as failures in multiple agents that have demonstrated efficacy in the metastatic setting. Finally, the current clinical trials will be reviewed, as well as complementary therapies including diet and exercise for survivors of colorectal cancer.

DNA Topoisomerase I Gene Copy Number and mRNA Expression Assessed as Predictive Biomarkers for Adjuvant Irinotecan in Stage II/III Colon Cancer

PURPOSE

Prospective-retrospective assessment of the TOP1 gene copy number and TOP1 mRNA expression as predictive biomarkers for adjuvant irinotecan in stage II/III colon cancer.

EXPERIMENTAL DESIGN

Formalin-fixed, paraffin-embedded tissue microarrays were obtained from an adjuvant colon cancer trial (PETACC3) where patients were randomized to 5-fluorouracil/folinic acid with or without additional irinotecan. TOP1 copy number status was analyzed by fluorescence in situ hybridization (FISH) using a TOP1/CEN20 dual-probe combination. TOP1 mRNA data were available from previous analyses.

RESULTS

TOP1 FISH and follow-up data were obtained from 534 patients. TOP1 gain was identified in 27% using a single-probe enumeration strategy (≥4 TOP1 signals per cell) and in 31% when defined by a TOP1/CEN20 ratio ≥ 1.5. The effect of additional irinotecan was not dependent on TOP1 FISH status.TOP1 mRNA data were available from 580 patients with stage III disease. Benefit of irinotecan was restricted to patients characterized by TOP1 mRNA expression ≥ third quartile (RFS: HRadjusted, 0.59;P= 0.09; OS: HRadjusted, 0.44;P= 0.03). The treatment by TOP1 mRNA interaction was not statistically significant, but in exploratory multivariable fractional polynomial interaction analysis, increasing TOP1 mRNA values appeared to be associated with increasing benefit of irinotecan.

CONCLUSIONS

In contrast to the TOP1 copy number, a trend was demonstrated for a predictive property of TOP1 mRNA expression. On the basis of TOP1 mRNA, it might be possible to identify a subgroup of patients where an irinotecan doublet is a clinically relevant option in the adjuvant setting of colon cancer.

MicroRNAs as novel predictive biomarkers and therapeutic targets in colorectal cancer

Colorectal cancer (CRC) is the third most common cancer in western countries. Despite significant improvement in available treatment options, CRC still remains the second leading cause of cancer-related death. Traditionally, 5-fluorouracil has been used as the main chemotherapy drug for treatment of metastatic CRC (mCRC). However, during the last two decades more effective chemotherapeutic agents such as oxaliplatin, irinotecan and the monoclonal antibodies cetuximab, panitumumab and bevacizumab have been used in clinical practice. More recently, the therapeutic armamentarium has been supplemented by the monoclonal antibodies bevacizumab, cetuximab and panitumumab as well as the protein-trap aflibercept and the small molecule multi-kinase inhibitor regorafenib. One of the major problems for the management of CRC is the inherent or acquired resistance to therapeutic approaches. The discovery of microRNAs (miRNAs), a class of small, endogenous, non-coding, single-stranded RNAs that play a role as post-transcriptional regulators, has added new dimensions to the diagnosis and treatment of cancer. Because miRNAs are important regulators of carcinogenesis, progression, invasion, angiogenesis and metastases in CRC, they might serve as potential predictive and prognostic factors and even as therapeutic targets themselves. Several miRNAs are already known to be dysregulated in CRCs and have been linked to biological processes involved in tumor progression and response to anti-cancer therapies. This review summarizes current therapeutic approaches for treating CRC and highlights the role of miRNAs as novel predictive biomarkers and potential drug targets in CRC patients.

Colorectal cancer

More than 1·2 million patients are diagnosed with colorectal cancer every year, and more than 600,000 die from the disease. Incidence strongly varies globally and is closely linked to elements of a so-called western lifestyle. Incidence is higher in men than women and strongly increases with age; median age at diagnosis is about 70 years in developed countries. Despite strong hereditary components, most cases of colorectal cancer are sporadic and develop slowly over several years through the adenoma-carcinoma sequence. The cornerstones of therapy are surgery, neoadjuvant radiotherapy (for patients with rectal cancer), and adjuvant chemotherapy (for patients with stage III/IV and high-risk stage II colon cancer). 5-year relative survival ranges from greater than 90% in patients with stage I disease to slightly greater than 10% in patients with stage IV disease. Screening has been shown to reduce colorectal cancer incidence and mortality, but organised screening programmes are still to be implemented in most countries.

A review of controversies in the management of colorectal cancers

Colorectal cancer (CRC) is one of the most common malignancies worldwide. Due to a higher incidence of CRC in the western hemisphere a significant amount of research was carried out and majority of the controversies could be resolved as far as management of CRC is concerned. Recently a number of significant advances were made in the field of CRC related to surgery, systemic therapy and radiotherapy. During the last decade we have witnessed introduction of minimally invasive surgery, incorporation of more effective newer chemotherapeutic regimes and targeted therapies and refinements in radiotherapy protocols. The demographics and clinical picture of CRC seems to be different in developing countries and there is paucity of CRC related studies from developing countries. In-order to update the practicing surgeons a review of conventional controversies of CRC surgery was performed and an update on the recent developments in the field of CRC was also presented in this article.

Role of microsatellite instability in the management of colorectal cancers

Microsatellite instability is the consequence of a deficient mismatch repair system. It has a key role in the diagnostic strategy of Lynch syndrome, where tumours are all characterized by the presence of this phenotype. Microsatellite instability is therefore essential in the selection of colorectal cancer patients in whom a germline analysis of Mismatch Repair genes is possibly indicated. Moreover, microsatellite instability tumours are associated with a good prognosis and a resistance to fluorouracil-based adjuvant chemotherapy, which has a clinical application mainly in stage II colon cancer patients in whom adjuvant chemotherapy has a less beneficial effect than in stage III and outcome in presence of microsatellite instability is excellent. Recent data suggest that impact of microsatellite instability on benefit to fluorouracil-based adjuvant chemotherapy is dependent of the molecular mechanism involved in this genetic instability since an improved survival has been reported with adjuvant fluorouracil in microsatellite instability colorectal cancers of germline origin but not in sporadic cases. Predictive value of microsatellite instability on response to fluorouracil/oxaliplatin adjuvant chemotherapy has been less evaluated but recent studies suggest that the favorable outcome of Microsatellite instability tumours is maintained in patients receiving FOLFOX.

Metastatic colorectal cancer: current treatment and future options for improved survival. Medical approach--present status

BACKGROUND

Metastatic colorectal cancer has a poor prognosis, and the majority of patients are left with palliative measures. The development seen using medical treatments are reviewed.

MATERIAL AND METHODS

A systematic approach to the literature-based evidence of effects from palliative chemotherapy and targeted drugs was aimed at.

RESULTS

The continuous improvements during the past 20-25 years have been documented in several large conclusive trials. At the end of the 1980s, the evidence that chemotherapy should be used at all was very limited, whereas presently most patients can be offered three lines of chemotherapy with or without a targeted drug based upon good scientific evidence. Median survival in trials has gradually improved from about 6 months to above 24 months in the most recent trials. Survival in the populations has, however, not improved to the same extent. Several important issues remain to be solved, such as the best sequence of treatments, what regimens to use in various situations, when to start and when to stop if a response is seen, whether cure may be possible in a small subset of patients, and socioeconomic issues. Integration of surgery and other local methods have further improved outcome for some individuals, but must be fine-tuned.

CONCLUSIONS

Progress has been rapid in advanced colorectal cancer. This is likely a result of well-designed trials in collaboration between academy and industry, showing a great interest in the disease. A multi-professional approach and future collaborations may hopefully introduce new treatment concepts, further improving outcome.

Microsatellite instability and Beta2-Microglobulin mutations as prognostic markers in colon cancer: results of the FOGT-4 trial

Background:

High-level microsatellite instability (MSI-H) has been reported as a prognostic marker in colon cancer. We here analysed the prognostic significance of MSI and mutations of the Beta2-Microglobulin (B2M) gene, which occur in about 30% of MSI-H colon cancer, in the cohort of the prospective FOGT-4 (Forschungsruppe Onkologie Gastrointestinale Tumoren, FOGT) trial.

Methods:

Microsatellite instability status was determined using standard protocols (NCI/ICG-HNPCC panel and CAT25) in 223 colon cancer lesions. Beta2-Microglobulin mutation status was evaluated by exon-wise sequencing in all MSI-H lesions.

Results:

Patients with MSI-H (n=34) colon cancer presented with a significantly lower risk of relapse after 12 months of follow-up compared with MSS (n=189) colon cancer patients (5 year time to relapse: MSI-H 0.82 vs MSS 0.66, P=0.03). No significant difference in overall survival was detected. Beta2-Microglobulin mutations were identified in 10 (29.4%) out of 34 MSI-H colon cancers and were associated with a complete absence of disease relapse or tumour-related death events (P=0.09).

Conclusion:

The risk of late disease relapse was significantly lower in patients with MSI-H compared with MSS colon cancer. Moreover, B2M mutations may contribute to the favourable outcome of MSI-H colon cancer patients and should therefore be evaluated as a potential prognostic marker in future clinical trials.

Personalized treatment of colorectal cancer

In the last 15 years, significant progress in the management of colorectal cancer (CRC) has been achieved with several new agents licensed extending median overall survival for stage IV disease to about 2 years. Treatment of CRC is stage-specific, multidisciplinary, and based on patient and tumor characteristics. Although especially early stages (0-III, according to Union for International Cancer Control) are treated with curative intent, patients with limited stage IV disease (liver and/or lung or localized peritoneal metastases) might still be curable in a multimodality approach including surgery, perioperative chemotherapy and/or radiotherapy. Despite the broad variety of prognostic factors, treatment decisions and selection of drugs are mainly based on clinicopathologic variables for early stage CRC, extent of disease, potential resectability, patients' eligibility to receive aggressive treatments including chemotherapy, surgery, and very few molecular markers such as KRAS mutational status for advanced disease. However, a tailored approach for the treatment of CRC taking into account all mentioned factors is currently recommended by national and international guidelines and will be discussed in this review.