Liquid biopsy for KRAS, NRAS and BRAF mutation testing in advanced colorectal cancer patients: the Argentinean experience

Objective: To analyze the frequency of KRAS, NRAS and BRAF hotspot mutations in circulating tumor DNA (ctDNA) from patients with metastatic colorectal cancer (mCRC). Methods: Observational, descriptive and retrospective study in mCRC patients with available ctDNA-based genotype of KRAS, NRAS and BRAF. Results: The frequencies of plasma mutations for KRAS, NRAS and BRAF were 34% (± 7), 4% (± 3) and 4% (± 3), respectively. Median overall survival of plasma-tested RAS/BRAF-mutated patients was 26.6 months (95% CI: 14.4-not estimable [NE]), while RAS/BRAF wild-type patients did not reach the median survival during follow-up. Median progression-free survival for RAS/BRAF wild-type and RAS/BRAF-mutated patients was 12 (95% CI: 7-NE) and 4 months (95% CI: 4-NE), respectively. Conclusion: Our work supports the utility of KRAS, NRAS and BRAF analysis in liquid biopsy from mCRC patients.

Molecular markers and prediction of response to immunotherapy in non-small cell lung cancer, an update

Immunotherapy represents one of the most promising therapeutic approaches in lung cancer, however 50% of lung cancer patients will not respond to this treatment, while others will have transitory or durable responses. Because side effects may be life threatening and treatment costs remain very high, the identification of predictive markers is mandatory and actually extensively studied. Factors that determine response to immune checkpoint inhibitors (ICI) are numerous including tumor microenvironment, immune tumor infiltrates, expression of immune checkpoint proteins (PD-1/PD-L1), gene expression signatures and molecular tumor profiles. Based on high impact factor publications and recent literature this review focuses on the potential predictive value of tumor molecular alterations and tumor mutation burden as predictive markers of response or resistance to ICI. We also discuss the role of circulating tumor DNA (ctDNA) to monitor ICI responses and propose an algorithm that integrates molecular markers upcoming recommendations for first line treatment.

Immuno-targeted combinations in oncogene-addicted non-small cell lung cancer

The identification of tumor "oncogenic drivers" and the subsequent development of targeted therapy represented a milestone in the treatment of lung cancer over the last years. Tumor genotyping has been incorporated into therapeutic decision making of advanced non-small cell lung cancer (NSCLC) since has become clear that individuals with actionable molecular alterations receiving a matched targeted agent certainly live longer and better. The recent understanding of biological mechanisms underlying cancer immune evasion has allowed the development of a new class of immunomodulatory agents which are able to reactivate host immune-response, offering the potential for long-term disease control and survival in a significant subgroup of lung cancer patients. The complementary therapeutic effects of these two different approaches suggested intriguing potential for therapeutic synergy with combination strategies. Indeed, immunotherapy could consolidate the dramatic but transient tumor responses achieved with targeted therapy into long-term survival benefit, due to the induction of specific anti-tumor memory. However, the great emphasis and expectations linked to immune-targeted combinations have been mostly disappointed by the initial controversial results of early-phase trials, raising relevant concerns about the use of these combinations for lung cancer treatment. This review briefly summarizes the basis of immunogenicity and immune escape in oncogene addicted NSCLC, providing an updated overview of clinical trials, with the final aim of defining the current unmet needs of immuno-targeted combinations in clinical practice.

Current and Future Molecular Testing in NSCLC, What Can We Expect from New Sequencing Technologies?

Recent changes in lung cancer care, including new approvals in first line and the introduction of high-throughput molecular technologies in routine testing led us to question ourselves on how deeper molecular testing may be helpful for the optimal use of targeted drugs. In this article, we review recent results in the scope of personalized medicine in lung cancer. We discuss biomarkers that have a therapeutic predictive value in lung cancer with a focus on recent changes and on the clinical value of large scale sequencing strategies. We review the use of second- and third-generation EGFR and ALK inhibitors with a focus on secondary resistance alterations. We discuss anti-BRAF and anti-MEK combo, emerging biomarkers as NRG1 and NTRKs fusions and immunotherapy. Finally, we discuss the different technical issues of comprehensive molecular profiling and show how large screenings might refine the prediction value of individual markers. Based on a review of recent publications (2012⁻2018), we address promising approaches for the treatment of patients with lung cancers and the technical challenges associated with the identification of new predictive markers.

Targeted therapies and immunotherapy in non-small-cell lung cancer

Non-small-cell lung cancer is still considered a difficult disease to manage because of its aggressiveness and resistance to common therapies. Chemotherapy remains the gold standard in nearly 80% of lung cancers, but clinical outcomes are discouraging, and the impact on median overall survival (OS) barely reaches 12 months. At the end of the last century, the discovery of oncogene-driven tumours completely changed the therapeutic landscape in lung cancers, harbouring specific gene mutations/translocations. Epidermal growth factors receptor (EGFR) common mutations first and anaplastic lymphoma kinase (ALK) translocations later led new insights in lung cancer biology knowledge. The use of specific tyrosine kinases inhibitors overturned the biological behaviour of EGFR mutation positive tumours and became a preclinical model to understand the heterogeneity of lung cancers and the mechanisms of drug resistance. In this review, we summarise the employment of targeted agents against the most representative biomolecular alterations and provide some criticisms of the therapeutic strategies.