Liquid biopsies to evaluate early therapeutic response in colorectal cancer

Assessments of TP53 and CTNNB1 gene hotspot mutations in circulating tumour DNA of hepatitis B virus-induced hepatocellular carcinoma

Background: Hepatitis B virus (HBV) infection is one of the major causes of chronic liver disease, which progresses from chronic hepatitis B (CHB) to fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). Early detection and laboratory-based screening of hepatocellular carcinoma are still major challenges. This study was undertaken to determine whether the cancer hallmark gene signatures that are released into circulation as circulating tumour DNA (ctDNA) can be used as a liquid biopsy marker for screening, early detection, and prognosis of HCC. Methods: A total of 130 subjects, including HBV-HCC (n = 80), HBV-cirrhotic and non-cirrhotic (n = 35), and healthy (n = 15) controls, were evaluated for TP53 and beta-catenin (CTNNB1) gene hotspot mutations in ctDNA by Sanger-based cycle sequencing and droplet digital PCR (ddPCR) assays. Mutation detection frequency, percentage mutant fractions, and their association with tumour stage, mortality, and smoking habits were determined. Results: Sanger-based cycle sequencing was carried out for 32 HCC patients. Predict SNP Tools analysis indicated several pathogenic driver mutations in the ctDNA sequence, which include p.D228N, p.C229R, p.H233R, p.Y234D, p.S240T, p.G245S, and p.R249M for TP53 gene exon 7 and p.S33T for CTNNB1 gene exon 3. The TP53 c.746G>T (p.R249M) mutation was detected predominately (25% cases) by sequencing, but there was no dominant mutation at position c.747G>T (p.R249S) that was reported for HBV-HCC patients. A dual-probe ddPCR assay was developed to determine mutant and wild-type copy numbers of TP53 (p.R249M and p.R249S) and CTNNB1 (p.S45P) and their percentage mutant fraction in all 130 subjects. The TP53 R249M and CTNNB1 S45P mutations were detected in 31.25% and 26.25% of HCC patients, respectively, with a high mutant-to-wild-type fraction percentage (1.81% and 1.73%), which is significant as compared to cirrhotic and non-cirrhotic patients. Poor survival was observed in HCC patients with combined TP53 and CTNNB1 gene driver mutations. The TP53 R249M mutation was also significantly (p < 0.0001) associated with smoking habits (OR, 11.77; 95% CI, 3.219-36.20), but not the same for the TP53 R249S mutation. Conclusion: Screening of ctDNA TP53 and CTNNB1 gene mutations by ddPCR may be helpful for early detection and identifying the risk of HCC progression.

Role of Biomarkers in Hepatocellular Carcinoma and Their Disease Progression

Hepatocellular carcinoma (HCC) is one of the third leading and common lethal cancers worldwide. Early detection of tumorigenesis of hepatocellular carcinoma is through ultrasonography, computerized tomography (CT) scans, and magnetic resonance imaging (MRI) scans; however, these methods are not up to the mark, so a search for an efficient biomarker for early diagnosis and treatment of hepatocarcinogenesis is important. Proteomic and genomic approaches aid to develop new promising biomarkers for the diagnosis of HCC at the early stages. These biomarkers not only help in prognosis but also provide better therapeutic intervention against HCC. Among the different biomarker candidates, liquid biopsy [including circulating tumor cells (CTCs) and circulating tumor DNA (ctDNA)] has recently emerged as a noninvasive detection technique for the characterization of circulating cells, providing a strong basis and early diagnosis for the individualized treatment of patients. This review provides the current understanding of HCC biomarkers that predict the risk of HCC recurrence.

ESMO recommendations on the use of circulating tumour DNA assays for patients with cancer: a report from the ESMO Precision Medicine Working Group

Circulating tumour DNA (ctDNA) assays conducted on plasma are rapidly developing a strong evidence base for use in patients with cancer. The European Society for Medical Oncology convened an expert working group to review the analytical and clinical validity and utility of ctDNA assays. For patients with advanced cancer, validated and adequately sensitive ctDNA assays have utility in identifying actionable mutations to direct targeted therapy, and may be used in routine clinical practice, provided the limitations of the assays are taken into account. Tissue based testing remains the preferred test for many cancer patients, due to limitations of ctDNA assays detecting fusion events and copy number changes, although ctDNA assays may be routinely used when faster results will be clinically important, or when tissue biopsies are not possible or inappropriate. Reflex tumour testing should be considered following a non-informative ctDNA result, due to false negative results with ctDNA testing. In patients treated for early-stage cancers, detection of molecular residual disease (MRD) or molecular relapse (MR), has high evidence of clinical validity in anticipating future relapse in many cancers. MRD/MR detection cannot be recommended in routine clinical practice, as currently there is no evidence for clinical utility in directing treatment. Additional potential applications of ctDNA assays, under research development and not recommended for routine practice, include identifying patients not responding to therapy with early dynamic changes in ctDNA levels, monitoring therapy for the development of resistance mutations prior to clinical progression, and in screening asymptomatic people for cancer. Recommendation for reporting of results, future development of ctDNA assays, and future clinical research are made.

Circulating Tumor DNA: An Emerging Tool in Gastrointestinal Cancers

Circulating tumor DNA (ctDNA) is tumor-derived fragmented DNA in the bloodstream that has come from primary or metastatic cancer sites. Neoplasm-specific genetic and epigenetic abnormalities are increasingly being identified through liquid biopsy: a novel, minimally invasive technique used to isolate and analyze ctDNA in the peripheral circulation. Liquid biopsy and other emerging ctDNA technologies represent a paradigm shift in cancer diagnostics because they allow for the detection of minimal residual disease in patients with early-stage disease, improve risk stratification, capture tumor heterogeneity and genomic evolution, and enhance ctDNA-guided adjuvant and palliative cancer therapy. Moreover, ctDNA can be used to monitor the tumor response to neoadjuvant and postoperative therapy in patients with metastatic disease. Using clearance of ctDNA as an endpoint for escalation/de-escalation of adjuvant chemotherapy for patients considered to have high-risk disease has become an important area of research. The possibility of using ctDNA as a surrogate for treatment response-including for overall survival, progression-free survival, and disease-free survival-is an attractive concept; this surrogate will arguably reduce study duration and expedite the development of new therapies. In this review, we summarize the current evidence on the applications of ctDNA for the diagnosis and management of gastrointestinal tumors. Gastrointestinal cancers-including tumors of the esophagus, stomach, colon, liver, and pancreas-account for one-quarter of global cancer diagnoses and contribute to more than one-third of cancer-related deaths. Given the prevalence of gastrointestinal malignancies, ctDNA technology represents a powerful tool to reduce the global burden of disease.

ctDNA to Guide Adjuvant Therapy in Localized Colorectal Cancer (CRC)

Currently, the standard treatment for patients with localized colorectal cancer (CRC) includes surgical resection followed by adjuvant chemotherapy based on clinicopathological features. Recurrence risk stratification in those patients is of utmost importance to guide clinicians to avoid both under- and overtreatment. Recently, the concept of minimal residual disease (MRD) has emerged as the detection of circulating tumor DNA (ctDNA) carrying tumor-specific genomic or epigenomic alterations in the bloodstream of patients after surgery. Emerging studies described how the detection of MRD is a powerful prognostic biomarker to identify patients at higher risk of recurrence and who will potentially benefit the most from a systemic adjuvant treatment. Based on that unprecedented finding, several clinical trials involving stage II and III CRC patients are ongoing evaluating the impact of ctDNA guided treatment by escalating or deescalating adjuvant chemotherapy based on ctDNA MRD detection. This review provides a critical overview of current perspectives of liquid biopsy in early-stage CRC including technical, biological, and clinical key points, as well as ongoing ctDNA-based clinical trials that ultimately aim to improve clinical outcomes of patients with CRC.

A higher ctDNA fraction decreases survival in regorafenib-treated metastatic colorectal cancer patients. Results from the regorafenib's liquid biopsy translational biomarker phase II pilot study

The predictive effect of circulating tumor DNA (ctDNA) in colorectal cancer (CRC) treatment is still highly discussed. The primary objective of our study was to investigate a possible prognostic/predictive value of ctDNA under regorafenib treatment. This prospective multicenter translational biomarker phase II pilot study enrolled 30 metastatic CRC patients (67% men, 33% women) treated with regorafenib. ctDNA was assessed in plasma before treatment start and at defined time points during administration. Measurement of tumor fraction as well as mutation and copy number analysis of CRC driver genes were performed by next-generation sequencing approaches. Multivariate analyses for survival and treatment efficacy were adjusted to age, gender and Eastern Cooperative Oncology Group. Disease control rate was 30%. Median tumor fraction at baseline was 18.5% (0-49.9). Mutations in CRC driver genes or genes involved in angiogenesis were identified in 25 patients (83.3%). KRAS mutations were detected in 13 of 14 KRAS-positive tumors; in three patients without KRAS mutation in the respective tumors, acquired mutations as a consequence of prior anti-EGFR treatment were detected. In a subset of patients, novel occurring mutations or focal amplifications were detected. A tumor fraction of 5% and higher at baseline was significantly associated with a decreased OS (P = .022; hazard ratio 3.110 (95% confidence interval: 1.2-8.2). ctDNA is detectable in a high proportion of mCRC patients. Higher ctDNA levels are associated with survival among regorafenib treatment. Moreover, our data highlight the benefit of a combined evaluation of mutations and somatic copy number alterations in advanced cancer patients.

Circulating tumor DNA correlates with microvascular invasion and predicts tumor recurrence of hepatocellular carcinoma

Background

To evaluate the feasibility of predicting tumor recurrence of hepatocellular carcinoma (HCC) patients after curative hepatectomy by detection of circulating tumor DNA (ctDNA) through droplet digital PCR (ddPCR).

Methods

HCC patients receiving surgical treatment were enrolled and peripheral blood samples before and after hepatectomy were collected. Four hotspot mutants, TP53-rs28934571 (c.747G>T), TRET-rs1242535815 (c.1-124C>T), CTNNB1-rs121913412 (c.121A>G) and CTNNB1-rs121913407 (c.133T>C) were selected to detect ctDNA and the mutant allele frequency (MAF) was calculated accordingly. The matched peripheral blood mononuclear cells (PBMCs) were used for Sanger sequencing. The clinicopathologic information of the patients was retrospectively analyzed and the predictive abilities for postoperative recurrence of different clinicopathologic parameters and ctDNA were compared.

Results

Eighty-one patients were enrolled and 70.4% (57/81) of them had detectable ctDNA before hepatectomy. Positive preoperative ctDNA status was related to larger tumor size (P=0.001), multiple tumor lesions (P=0.001), microvascular invasion (MVI) (P<0.001), advanced BCLC stages (P<0.001) and shorter disease free survival (DFS) (P<<0.001) and overall survival (OS) (P<<0.001). Multivariate analysis showed that detectable ctDNA was the independent risk factor for postoperative recurrence. Moreover, receiver operating characteristic (ROC) curves proved that ctDNA possessed the second largest area under the curve (AUC) in foretelling postoperative recurrence right after BCLC stage. For patients after surgery, the alterations of MAF were also correlated to postsurgical recurrence. Patients with increased MAF had more incidences of MVI (P=0.016) and recurrence (P<0.001). At the same time, Kaplan-Meier curves revealed a significant shorter DFS and OS in the patients with increased MAF compared to the patients with decreased MAF (P<0.001 and P=0.0045, respectively) and ROC curves showed MAF to possess the greatest AUC among all the indices for postoperative recurrence.

Conclusions

Digital droplets PCR assessment of specific gene combination through ctDNA possesses potential prognostic value in HCC patients undergoing surgical treatment.

Assessing the Concordance of Genomic Alterations between Circulating-Free DNA and Tumour Tissue in Cancer Patients

Somatic alterations to the genomes of solid tumours, which in some cases represent actionable drivers, provide diagnostic and prognostic insight into these complex diseases. Spatial and longitudinal tracking of somatic genomic alterations (SGAs) in patient tumours has emerged as a new avenue of investigation, not only as a disease monitoring strategy, but also to improve our understanding of heterogeneity and clonal evolution from diagnosis through disease progression. Furthermore, analysis of circulating-free DNA (cfDNA) in the so-called "liquid biopsy" has emerged as a non-invasive method to identify genomic information to inform targeted therapy and may also capture the heterogeneity of the primary and metastatic tumours. Considering the potential of cfDNA analysis as a translational laboratory tool in clinical practice, establishing the extent to which cfDNA represents the SGAs of tumours, particularly actionable driver alterations, becomes a matter of importance, warranting standardisation of methods and practices. Here, we assess the utilisation of cfDNA for molecular profiling of SGAs in tumour tissue across a broad range of solid tumours. Moreover, we examine the underlying factors contributing to discordance of detected SGAs between cfDNA and tumour tissue.

Clinical Utility of Analyzing Circulating Tumor DNA in Patients with Metastatic Colorectal Cancer

Multiple genomic changes caused by clonal evolution induced by therapeutic pressure and corresponding intratumoral heterogeneity have posed great challenges for personalized therapy against metastatic colorectal cancer (mCRC) in the past decade. Liquid biopsy has emerged as an excellent molecular diagnostic tool for assessing predominant spatial and temporal intratumoral heterogeneity with minimal invasiveness.Previous studies have revealed that genomic alterations in RAS, BRAF, ERBB2, and MET, as well as other cancer-related genes associated with resistance to anti-epidermal growth factor receptor (EGFR) therapy, can be analyzed with high diagnostic accuracy by circulating tumor DNA (ctDNA) analysis. Furthermore, by longitudinally monitoring ctDNAs during anti-EGFR therapy, the emergence of genomic alterations can be detected as acquired resistance mechanisms in specific genes, mainly those associated with the mitogen-activated protein kinase signaling pathway. Analysis of ctDNA can also identify predictive biomarkers to immune checkpoint inhibitors, such as mutations in mismatch repair genes, microsatellite instability-high phenotype, and tumor mutation burden. Some prospective clinical trials evaluating targeted agents for genomic alterations in ctDNA or exploring resistance biomarkers by monitoring of ctDNA are ongoing.To determine the value of ctDNA analysis for decision-making by more accurate molecular marker-based selection of patients and identification of resistance mechanisms to targeted therapies or sensitive biomarkers for immune checkpoint inhibitors, clinical trials must be refined to evaluate the efficacy of study treatment in patients with targetable genomic alterations confirmed by ctDNA analysis, and resistance biomarkers should be explored by monitoring ctDNA in large-scale clinical trials. In the near future, ctDNA analysis will play an important role in precision medicine for mCRC. IMPLICATIONS FOR PRACTICE: Treatment strategies for metastatic colorectal cancer (mCRC) are determined according to the molecular profile, which is confirmed by analyzing tumor tissue. Analysis of circulating tumor DNA (ctDNA) may overcome the limitations of tissue-based analysis by capturing spatial and temporal intratumoral heterogeneity of mCRC. Clinical trials must be refined to test the value of ctDNA analysis in patient selection and identification of biomarkers. This review describes ctDNA analysis, which will have an important role in precision medicine for mCRC.

LGALS4, CEACAM6, TSPAN8, and COL1A2: Blood Markers for Colorectal Cancer-Validation in a Cohort of Subjects With Positive Fecal Immunochemical Test Result. Clin Colorectal Cancer. 2018;17:e217-e228. [PMID: 29352642 DOI: 10.1016/j.clcc.2017.12.002]

BACKGROUND

A noninvasive blood test for the early detection of colorectal cancer (CRC) is highly required. We evaluated a panel of 4 mRNAs as putative markers of CRC.

MATERIALS AND METHODS

We tested LGALS4, CEACAM6, TSPAN8, and COL1A2, referred to as the CELTiC panel, using quantitative reverse transcription polymerase chain reaction, on subjects with positive fecal immunochemical test (FIT) results and undergoing colonoscopy. Using a nonparametric test and multinomial logistic model, FIT-positive subjects were compared with CRC patients and healthy individuals.

RESULTS

All the genes of the CELTiC panel displayed statistically significant differences between the healthy subjects (n = 67), both low-risk (n = 36) and high-risk/CRC (n = 92) subjects, and those in the negative-colonoscopy, FIT-positive group (n = 36). The multinomial logistic model revealed LGALS4 was the most powerful marker discriminating the 4 groups. When assessing the diagnostic values by analysis of the areas under the receiver operating characteristic curves (AUCs), the CELTiC panel reached an AUC of 0.91 (sensitivity, 79%; specificity, 94%) comparing normal subjects to low-risk subjects, and 0.88 (sensitivity, 75%; specificity, 87%) comparing normal and high-risk/CRC subjects. The comparison between the normal subjects and the negative-colonoscopy, FIT-positive group revealed an AUC of 0.93 (sensitivity, 82%; specificity, 97%).

CONCLUSION

The CELTiC panel could represent a useful tool for discriminating subjects with positive FIT findings and for the early detection of precancerous adenomatous lesions and CRC.

Shallow Whole Genome Sequencing on Circulating Cell-Free DNA Allows Reliable Noninvasive Copy-Number Profiling in Neuroblastoma Patients

Purpose: Neuroblastoma (NB) is a heterogeneous disease characterized by distinct clinical features and by the presence of typical copy-number alterations (CNAs). Given the strong association of these CNA profiles with prognosis, analysis of the CNA profile at diagnosis is mandatory. Therefore, we tested whether the analysis of circulating cell-free DNA (cfDNA) present in plasma samples of patients with NB could offer a valuable alternative to primary tumor DNA for CNA profiling.Experimental Design: In 37 patients with NB, cfDNA analysis using shallow whole genome sequencing (sWGS) was compared with arrayCGH analysis of primary tumor tissue.Results: Comparison of CNA profiles on cfDNA showed highly concordant patterns, particularly in high-stage patients. Numerical chromosome imbalances as well as large and focal structural aberrations including MYCN and LIN28B amplification and ATRX deletion could be readily detected with sWGS using a low input of cfDNA.Conclusions: In conclusion, sWGS analysis on cfDNA offers a cost-effective, noninvasive, rapid, robust and sensitive alternative for tumor DNA copy-number profiling in most patients with NB. Clin Cancer Res; 23(20); 6305-14. ©2017 AACR.

Heterogeneity in the colorectal primary tumor and the synchronous resected liver metastases prior to and after treatment with an anti-EGFR monoclonal antibody

Molecular heterogeneity between primary tumors (PTs) and synchronous resected liver metastasis in colorectal cancer (CRC) has potential relevance in treatment strategies. Next-generation sequencing (NGS) may be able to increase the chances of identifying multiple molecular driver alterations, calling for therapy. The aim of the present study was to evaluate mutations in PT and synchronous resected liver metastases for patients with Kirsten rat sarcoma 2 viral oncogene homolog (KRAS) exon 2 wild-type metastatic (m)CRC who underwent chemotherapy (CT) featuring an anti-epidermal growth factor receptor (EGFR) monoclonal antibody. Genomic analysis was performed on 54 lesions from 7 patients with mCRC. For each patient, a PT biopsy or a surgical specimen was obtained prior to CT, and the PT and all liver metastases resected following CT were analyzed. DNA libraries were generated using the Ion AmpliSeq Colon and Lung Cancer Panel, assessing the most frequent somatic mutations in 22 genes involved in colon tumorigenesis, and sequencing was performed on an Ion Personal Genome Machine system. A partial response was achieved in all the patients, with a median progression free survival time of 11 months (range, 3-21 months). All the patients were subjected to surgical liver metastasis resection. The median overall survival time was 31 months (range, 4-46 months). Molecular analysis of the genes correlated with the target therapy, suggesting significant intratumor heterogeneity, as revealed by the different mutational landscape of certain PTs and synchronous resected liver metastases following systemic therapy when compared with the PT prior to treatment. In particular, the loss and acquisition of mutations in KRAS, neuroblastoma RAS viral oncogene homolog (NRAS), tumor protein p53 (TP53), the p110α catalytic subunit of phosphoinositide 3-kinase (PIK3CA), F-box/WD repeat-containing protein 7 (FBXW7) and phosphatase and tensin homolog (PTEN) were observed. In addition, one patient developed a mucinous pattern following systemic CT. Taken together, the results of the present study demonstrated that intratumor heterogeneity is likely to affect the response to therapy, and to drive acquired resistance to targeted agents. The preliminary data also suggest a potential role for NGS in the evaluation of biological drug resistance, affecting future sequential treatment strategies.

Advances in Circulating Tumor DNA Analysis

The analysis of cell-free circulating tumor DNA (ctDNA) is a very promising tool and might revolutionize cancer care with respect to early detection, identification of minimal residual disease, assessment of treatment response, and monitoring tumor evolution. ctDNA analysis, often referred to as "liquid biopsy" offers what tissue biopsies cannot-a continuous monitoring of tumor-specific changes during the entire course of the disease. Owing to technological improvements, efforts for the establishment of preanalytical and analytical benchmark, and the inclusion of ctDNA analyses in clinical trial, an actual clinical implementation has come within easy reach. In this chapter, recent advances of the analysis of ctDNA are summarized starting from the discovery of cell-free DNA, to methodological approaches and the clinical applicability.

Detecting Circulating Tumor DNA in Hepatocellular Carcinoma Patients Using Droplet Digital PCR Is Feasible and Reflects Intratumoral Heterogeneity

PURPOSE

Circulating tumor DNA (ctDNA) is increasingly recognized as liquid biopsy to profile tumor genome. Droplet digital PCR (ddPCR) is a highly sensitive and easily operable platform for mutant detection. Here, we tried to detect ctDNA in hepatocellular carcinoma (HCC) patients using ddPCR.

METHODS

Studies sequencing the genome of HCCs and COSMIC (Catalogue of Somatic Mutations in Cancer) database were reviewed to identify hotspot mutations. Circulating cell-free DNAs (cfDNAs) extracted from 1 ml preoperative plasma sample were analyzed to detect circulating mutants using ddPCR. The DNAs from matched tumor and adjacent liver tissues or peripheral blood mononuclear cells (PBMCs) were sequenced to identify the origin of circulating mutants.

RESULTS

Forty-eight HCC patients were enrolled and four gene loci, TP53 (c.747G>T), CTNNB1 (c.121A>G, c.133T>C), and TERT (c.1-124C>T) were chosen as targets for ddPCR assay. Serial dilution demonstrated the detection limit of ddPCR to be 0.01%. Twenty-seven patients (56.3%, 27/48) were found to have at least one kind of circulating mutants, with the mutant allele frequency ranging from 0.33% to 23.7%. Six patients (22.2%, 6/27) also had matched mutants in tumor tissues while none of the mutants were detected in adjacent liver tissues or PBMCs in all patients, which excluded the nonneoplastic origin of these circulating mutants and qualified them as ctDNA.

CONCLUSIONS

ctDNA could be readily detected in HCC patients by targeting hotspot mutations using ddPCR and might reflect intratumoral heterogeneity. ctDNA detecting may serve as a promising liquid biopsy in HCC management.

Therapeutic Strategies in Diseases of the Digestive Tract - 2015 and Beyond Targeted Therapies in Colon Cancer Today and Tomorrow

BACKGROUND

Colorectal cancer (CRC) is the third most common cancer type in Western countries. Significant progress has been made in the last decade in the therapy of metastatic CRC (mCRC) with a median overall survival (OS) of patients exceeding 30 months. The integration of biologic targeted therapies and anti-epidermal growth factor receptor (EGFR) monoclonal antibodies (MABs) in the treatment of patients with genomically selected all-RAS wild-type mCRC leads to a significant progress in advanced incurable disease state. After the introduction of the anti-VEGF MAB bevacizumab, the FDA approved with ramucirumab the second antiangiogenic MAB for the mCRC treatment. Further new drugs are on the horizon and new diagnostic tools will be introduced soon.

KEY MESSAGES

Molecular heterogeneity of mCRC has been recognized as pivotal in the evolution of clonal populations during anti-EGFR therapies. Mutations in RAS genes predict a lack of response to anti-EGFR MABs. Mutations in the mitogen-activated protein kinase-phosphoinositide 3-kinase pathways like BRAF or PIK3CA mutations or HER2/ERBB2 or MET amplifications bypass EGFR signaling and also may confer resistance to anti-EGFR MABs. HER2/ERBB2 amplification is a further driver of resistance to anti-EGFR MABs in mCRC. The phase II study of HER2 Amplification for Colo-Rectal Cancer Enhanced Stratification (HERACLES) discovers that a dual HER2-targeted therapy may be an option for HER2-amplified mCRC. The mismatch repair deficiency predicts responsiveness to an immune checkpoint blockade with the anti-PD-1 immune checkpoint inhibitor pembrolizumab.

CONCLUSIONS

The understanding of primary (de novo) and secondary (acquired) resistance to anti-EGFR therapies, new targeted therapies, immuno-oncology and about predictive biomarkers in mCRC is guiding the development of rational therapeutic strategies. Combinations of targeted therapies are necessary to effectively treat drug-resistant cancers. Liquid biopsy is an upcoming new tool in the primary diagnosis and follow-up analysis of mutations in circulating tumor DNA.

Cancer Genomics

Modern cancer genomics has emerged from the combination of the Human Genome Reference, massively parallel sequencing, and the comparison of tumor to normal DNA sequences, revealing novel insights into the cancer genome and its amazing diversity. Recent developments in applying our knowledge of cancer genomics have focused on the utility of these data for clinical applications. The emergent results of this translation into the clinical setting already are changing the clinical care and monitoring of cancer patients.