Circulating Tumour DNA in Melanoma-Clinic Ready?

Role of Surgery for Metastatic Melanoma in the Era of Checkpoint Blockade

Treatment paradigms have shifted with the introduction of checkpoint inhibitors, facilitating less extensive surgical procedures in some scenarios. Resection and adjuvant therapy are key components in patients with locally advanced or limited metastatic disease. Alternately, these patient populations may benefit from peri-operative systemic therapy based on recent clinical trial data. Resection is also integral to administering tumor infiltrating lymphocyte therapy in patients with treatment-refractory, unresectable melanoma. The role of surgery continues to evolve, and ranges the spectrum from resection with curative intent, to palliative interventions intended to effectively manage symptoms or disease-related complications.

Using liquid biopsies to guide treatment and monitor response in BRAF V600E positive adenocarcinoma of unknown primary

Liquid biopsies using circulating tumour DNA (ctDNA) have emerged as an alternative to conventional biopsies. They can be used to aid in diagnosing and selecting an agent for treatment and can possibly be used to monitor disease response to treatment. In this report, we present a patient who initially presented with lower abdominal pain. Imaging showed extensive retroperitoneal lymphadenopathy and lymph node biopsy demonstrated poorly differentiated carcinoma. Further workup did not reveal a primary lesion, but his genetic analysis revealed a BRAF V600E mutation and CD274 amplification which was used to guide treatment of the adenocarcinoma as a melanoma of unknown primary. He was initiated on ipilimumab and nivolumab and his ctDNA levels showed rapid improvement. After treatment was stopped due to adverse events, he was monitored via ctDNA, with an increase prompting repeat imaging that demonstrated enlargement of his lesions prompting a resumption of treatment.

Circulating tumor DNA predicts tumor progression and poor survival in patients with stage III melanoma

Data regarding circulating tumor DNA (ctDNA) in stage III melanoma are scarce. The main objective was to analyze the usefulness of ctDNA determination in predicting tumor progression in patients with stage III melanoma. A prospective multicenter study was designed based on patients with stage III cutaneous melanoma. We studied BRAF, NRAS, and TERT promoter mutations in primary or metastatic tumors. Blood samples were collected after detecting a positive lymph node by sentinel lymph node biopsy; preoperative in patients with lymph node metastasis; or before any treatment in patients with confirmed unresectable lymph node metastasis or in-transit metastasis; 4 weeks after lymph node surgery (postoperative); and every 3 or 6 months after the baseline sample. From each sample, we isolated cell-free DNA, and previously identified mutations were searched for to identify ctDNA. ctDNA was detected in 21 (21/48, 43.8%) patients. Recurrence at a distant site and recurrence in two or more locations were associated with ctDNA detection at the time of recurrence (P < 0.05). Plasma ctDNA detection at any time during follow-up was significantly associated with progression (P = 0.011), overall mortality (P < 0.001), and melanoma-specific death (P < 0.001). We did not find an association between detectable ctDNA before surgery and disease progression; however, patients with detectable postsurgical ctDNA exhibited a lower recurrence-free survival, overall survival, and melanoma-specific survival. Prospective longitudinal blood sampling for the identification of ctDNA provides information regarding recurrence and survival.

Circulating Tumor DNA in High-Risk Stage II/III Cutaneous Melanoma: A Feasibility Study

BACKGROUND

Adjuvant therapies reduce recurrence in patients with clinical stage IIB/IIC/III melanoma; however, better risk stratification and patient selection are needed. Circulating tumor DNA (ctDNA) as a marker of micrometastatic residual disease is being explored for such purposes in other malignancies. We aimed to explore the feasibility of serial ctDNA monitoring in patients with stage II/III melanoma, as well as the association of ctDNA elevation with disease burden and outcomes.

METHODS

A single-institution prospective study was conducted on patients with clinical stage IIB/IIC/III melanoma. Primary tumor was sent to Natera for generation of a tumor-informed mPCR-NGS assay (Signatera™). Peripheral blood was collected for analysis at pre-specified timepoints. Patients were stratified by ctDNA elevations both pre- and postoperatively to compare tumor characteristics and recurrence-free survival (RFS).

RESULTS

Overall, 30 patients were enrolled. The median Breslow depth was 4.4 mm and 70% were ulcerated. Signatera™ assays were successfully created for all 30 patients. Median follow-up from the time of surgery was 16 months and 13 patients recurred with median RFS of 19 months. Eight of these 13 patients (62%) had detectable ctDNA levels predating their clinical or radiographic recurrence. Elevated ctDNA at the first post-operative timepoint was associated with worse RFS.

CONCLUSIONS

ctDNA monitoring is feasible for patients with high-risk cutaneous melanoma. Our findings suggest that detectable ctDNA post-operatively may be associated with worse outcomes. Elevations during surveillance may predict subsequent clinical recurrence; however, the role of ctDNA in adjuvant therapy decision-making and surveillance is not yet ready for broad application.

Circulating tumor DNA to monitor treatment response in solid tumors and advance precision oncology

Circulating tumor DNA (ctDNA) has emerged as a dynamic biomarker in cancer, as evidenced by its increasing integration into clinical practice. Carrying tumor specific characteristics, ctDNA can be used to inform treatment selection, monitor response, and identify drug resistance. In this review, we provide a comprehensive, up-to-date summary of ctDNA in monitoring treatment response with a focus on lung, colorectal, and breast cancers, and discuss current challenges and future directions.

Circulating tumor DNA for surveillance in high-risk melanoma patients: a study protocol

BACKGROUND AND PURPOSE

Melanoma is one of the deadliest skin cancers and challenges clinicians worldwide due to rising incidence, potential aggressiveness, and propensity for metastasis, necessitating comprehensive follow-up programs after primary treatment. Circulating tumor DNA (ctDNA) is a promising biomarker that may indicate disease progression earlier than traditional surveillance methods, including 18F-FDG PET-CT, ultrasound, and clinical examination. This study examines ctDNA detection in blood as a minimally invasive method for early identification of progression following primary treatment of melanoma. The aim is to overcome the limitations of current methods, potentially improving prognosis and survival.

PATIENTS/MATERIAL AND METHODS

Patients with high risk of recurrence following primary treatment of melanoma are offered inclusion. Blood sampling is performed at each follow-up visit. In case of recurrence, patient-specific mutations are identified through next-generation sequencing (NGS) of formalin and paraffin embedded tissue from diagnostic routine. Detection of mutation-specific ctDNA is performed on blood using digital droplet polymerase chain reaction (ddPCR) or NGS. This allows determination of the value and sensitivity of ctDNA for early detection of recurrence.

RESULTS AND INTERPRETATION

For validation purposes, we conducted a small pilot study using blood samples from 10 patients who had experienced recurrence and had a clinically confirmed BRAF V600E mutation. Detection of BRAF V600E ctDNA using ddPCR varied from 0/5 (0%) in DNA harvested from 4 mL plasma, to 3/5 (60%) in DNA from 8 mL of plasma. These results show promise and highlight the importance of high sensitivity and sampling volumes to ensure accurate detection of low levels of ctDNA.

The role of circulating tumor DNA in melanomas of the uveal tract

Melanoma of the uveal tract or uveal melanoma (UM) originates from melanocytes of the eye and is the most common intraocular malignancy in adults. Despite considerable advances in diagnostic procedures and treatments, prognosis remains poor in those with advanced disease. Accordingly, although current treatments have an excellent local disease control rate, approximately 50% of patients develop metastatic relapse within 10 years. The high risk for metastatic disease with a variable and often long latency period is thought to be due to early spread of cancer cells disseminating into organs such as the liver, followed by a period of dormancy, before the eventual emergence of radiologically measurable disease. Early detection of disease relapse or metastasis is therefore crucial to allow timely treatment and ultimately improve patient outcome. Recently, advances in minimally-invasive liquid biopsy techniques and biomarkers such as circulating tumor DNA (ctDNA) have demonstrated potential to transform the field of cancer care by aiding diagnosis, prognosis and monitoring of various cancer types. UM is particularly suitable for ctDNA-based approaches due to the relatively well-characterized spectrum of genetic mutations, along with the inherent difficulties and risks associated with getting sufficient tumor samples via traditional biopsy methods. Key potential advantage of ctDNA are the detection of molecular residual disease (MRD) in patients post definitive treatment, and in the early identification of metastasis. This is particularly relevant contemporarily with the recent demonstration of tebentafusp improving survival in metastatic UM patients, and opens avenues for further research to investigate the potential utilization of tebentafusp combined with ctDNA-based strategies in adjuvant settings and early intervention for MRD. The present review illustrates the current understanding of ctDNA-based strategies in UM, discusses the potential clinical applications, explores the potential of utilizing ctDNA in UM MRD in the context of an ongoing clinical trial, and highlights the challenges that need to be overcome prior to routine clinical implementation.

Patterns in progression from early-stage melanoma to late-stage melanoma: implications for survivorship follow-up

Aim: This study determined the characteristics of patients with early-stage melanoma (IA-IIA) who later had stage IV recurrence.Patients & methods: We retrospectively examined 880 melanoma patients and identified those who progressed to stage IV disease from an initial early-stage (n = 50).Results: We observed a median latent period of 4 years between early-stage diagnosis and metastatic disease. More patients (54%) developed metastatic disease 4 years or later from the initial diagnosis. 34% had regular dermatology appointments, and 30% had regular oncology follow-up. Lung and brain were the most common metastatic sites.Conclusion: Long term monitoring beyond 4 years and a low threshold for performing symptom-guided imaging, particularly if pulmonary or neurologic symptoms occur, may be prudent after early-stage melanoma diagnosis.

Durable complete response in a patient with leptomeningeal melanoma after treatment with dabrafenib, trametinib, and nivolumab

Leptomeningeal disease (LMD) is a devastating complication of melanoma with a dismal prognosis. We present the case of a young man with stage IV BRAF V600E mutant melanoma with lung, lymph node, and brain metastases initially treated with ipilimumab and nivolumab, who subsequently developed LMD. Upon change to BRAF/MEK targeted therapy with nivolumab, a durable complete response was achieved and remains ongoing, off treatment, 7 years from diagnosis. Management of symptomatic LMD remains a critical unmet clinical challenge, with limited clinical trial data. This exceptional case is instructive, as the first published case of the use of the triplet, and the first durable response with therapy discontinuation, in melanoma LMD. The triple-drug regimen may be considered a viable option in fit patients. This case highlights the potential for long-term disease control and the critical and urgent need to develop clinical trials inclusive of patients with LMD to define the best treatment strategies.

Predictive Significance of Combined Plasmatic Detection of BRAF Mutations and S100B Tumor Marker in Early-Stage Malignant Melanoma

BACKGROUND

Melanoma is the most aggressive skin cancer with ability to recur also after early-stage tumor surgery. The aim was to identify early-stage melanoma patients at high risk of recurrence using liquid biopsy, estimating of mutated BRAF ctDNA and the level of tumor marker S100B in plasma.

METHODS

Eighty patients were enrolled in the study. BRAF V600E mutation was determined in FFPE tissue and plasma samples using ultrasensitive ddPCR with pre-amplification. The level of S100B was determined in plasma by immunoassay chemiluminescent method.

RESULTS

The best prediction of melanoma recurrence after surgery was observed in patients with combined high level of S100B (S100Bhigh) and ctDNA BRAFV600E (BRAFmut) in preoperative (57.1% vs. 12.5%, p = 0.025) as well as postoperative blood samples (83.3% vs. 14.3%, resp., p = 0.001) in comparison with low S100B and BRAF wild-type. Similarly, patients with preoperative and postoperative S100Bhigh and BRAFmut experienced worse prognosis (DFI p = 0.05, OS p = 0.131 and DFI p = 0.001, OS = 0.001, resp.).

CONCLUSION

We observed the benefit of the estimation of combination of S100B and ctDNA BRAFmut in peripheral blood for identification of patients at high risk of recurrence and unfavorable prognosis.

SIGNIFICANCE

There is still no general consensus on molecular markers for deciding the appropriateness of adjuvant treatment of early-stage melanoma. We have shown for the first time that the combined determination of the ctDNA BRAFmut oncogene (liquid biopsy) and the high level of tumor marker S100B in pre- and postoperative plasma samples can identify patients with the worst prognosis and the highest risk of tumor recurrence. Therefore, modern adjuvant therapy would be appropriate for these patients with resectable melanoma, regardless of disease stage.

The Importance of Predictive Biomarkers and Their Correlation with the Response to Immunotherapy in Solid Tumors-Impact on Clinical Practice

Background/Objectives: Immunotherapy has changed the therapeutic approach for various solid tumors, especially lung tumors, malignant melanoma, renal and urogenital carcinomas, demonstrating significant antitumor activity, with tolerable safety profiles and durable responses. However, not all patients benefit from immunotherapy, underscoring the need for predictive biomarkers that can identify those most likely to respond to treatment. Methods: The integration of predictive biomarkers into clinical practice for immune checkpoint inhibitors (ICI) holds great promise for personalized cancer treatment. Programmed death ligand 1 (PD-L1) expression, tumor mutational burden (TMB), microsatellite instability (MSI), gene expression profiles and circulating tumor DNA (ctDNA) have shown potential in predicting ICI responses across various cancers. Results: Challenges such as standardization, validation, regulatory approval, and cost-effectiveness must be addressed to realize their full potential. Predictive biomarkers are crucial for optimizing the clinical use of ICIs in cancer therapy. Conclusions: While significant progress has been made, further research and collaboration among clinicians, researchers, and regulatory institutes are essential to overcome the challenges of clinical implementation. However, little is known about the relationship between local and systemic immune responses and the correlation with response to oncological therapies and patient survival.

Circulating tumor DNA-based assessment of molecular residual disease in non-metastatic melanoma

In patients with resected non-metastatic melanoma, the liquid biopsy for the assessment of molecular residual disease (MRD) by circulating tumour DNA (ctDNA) represents a promising tool to stratify the risk and to monitor tumour evolution. However, its validation requires the demonstration of analytical validity, clinical validity and utility. Indeed, the development of sensitive and specific assays can optimize prognostication and eventually help clinicians to modulate adjuvant treatments, in order to improve clinical outcomes. Data about ctDNA-guided prognosis stratification is emerging, but clinical trials assessing ctDNA-guided therapeutic decisions are still ongoing. This review aims to depict the role of ctDNA-based MRD assessment in patients with non-metastatic melanoma and to provide a roadmap to face challenges for its introduction into clinical practice.

Advances in Melanoma: From Genetic Insights to Therapeutic Innovations

Advances in melanoma research have unveiled critical insights into its genetic and molecular landscape, leading to significant therapeutic innovations. This review explores the intricate interplay between genetic alterations, such as mutations in BRAF, NRAS, and KIT, and melanoma pathogenesis. The MAPK and PI3K/Akt/mTOR signaling pathways are highlighted for their roles in tumor growth and resistance mechanisms. Additionally, this review delves into the impact of epigenetic modifications, including DNA methylation and histone changes, on melanoma progression. The tumor microenvironment, characterized by immune cells, stromal cells, and soluble factors, plays a pivotal role in modulating tumor behavior and treatment responses. Emerging technologies like single-cell sequencing, CRISPR-Cas9, and AI-driven diagnostics are transforming melanoma research, offering precise and personalized approaches to treatment. Immunotherapy, particularly immune checkpoint inhibitors and personalized mRNA vaccines, has revolutionized melanoma therapy by enhancing the body's immune response. Despite these advances, resistance mechanisms remain a challenge, underscoring the need for combined therapies and ongoing research to achieve durable therapeutic responses. This comprehensive overview aims to highlight the current state of melanoma research and the transformative impacts of these advancements on clinical practice.

Prognostic biomarkers in melanoma: a 2023 update from clinical trials in different therapeutic scenarios

INTRODUCTION

Over the past decade, significant advancements in the field of melanoma have included the introduction of a new staging system and the development of immunotherapy and targeted therapies, leading to changes in substage classification and impacting patient prognosis. Despite these strides, early detection remains paramount. The quest for dependable prognostic biomarkers is ongoing, given melanoma's unpredictable nature, especially in identifying patients at risk of relapse. Reliable biomarkers are critical for informed treatment decisions.

AREAS COVERED

This review offers a comprehensive review of prognostic biomarkers in the context of clinical trials for immunotherapy and targeted therapy. It explores different clinical scenarios, including adjuvant, metastatic, and neo-adjuvant settings. Key findings suggest that tumor mutational burden, PD-L1 expression, IFN-γ signature, and immune-related factors are promising biomarkers associated with improved treatment responses.

EXPERT OPINION

Identifying practical prognostic factors for melanoma therapy is challenging due to the tumor's heterogeneity. Promising biomarkers include tumor mutational burden (TMB), circulating tumor DNA, and those characterizing the tumor microenvironment, especially the immune component. Future research should prioritize large-scale, prospective studies to validate and standardize these biomarkers, emphasizing clinical relevance and real-world applicability. Easily accessible biomarkers have the potential to enhance the precision and effectiveness of melanoma management.

Breaking Down Barriers to Detection and Care in Early-Age-Onset Colorectal Cancer in Canada

The second Early-Age-Onset Colorectal Cancer Symposium, convened in October 2022, sought solutions to the barriers to early detection and care for colorectal cancer in Canada. This meeting built on a previous symposium, held in 2021 and reported in this journal. Early-age-onset colorectal cancer (EAOCRC) affects increasing numbers of people under the age of 50 in Canada and throughout the developed world. Two main themes emerged from the meeting: the importance of timely detection, and the need for a tailored approach to the care of EAOCRC. Early detection is crucial, especially in light of the later stage at diagnosis and unique tumour characteristics. Symposium participants were strongly in favour of reducing the age of eligibility for screening from 50 to 45, and promoting the development of non-invasive screening techniques such as testing for circulating tumour DNA and biomarkers. Leading approaches to care were described and discussed, which meet the unique treatment needs of younger CRC patients. Multidisciplinary practices within and outside Canada address such factors as fertility, family roles, education, careers and financial responsibilities. These models can be applied in treatment centres across the country.

An update on methods for detection of prognostic and predictive biomarkers in melanoma

The approval of immunotherapy for stage II-IV melanoma has underscored the need for improved immune-based predictive and prognostic biomarkers. For resectable stage II-III patients, adjuvant immunotherapy has proven clinical benefit, yet many patients experience significant adverse events and may not require therapy. In the metastatic setting, single agent immunotherapy cures many patients but, in some cases, more intensive combination therapies against specific molecular targets are required. Therefore, the establishment of additional biomarkers to determine a patient's disease outcome (i.e., prognostic) or response to treatment (i.e., predictive) is of utmost importance. Multiple methods ranging from gene expression profiling of bulk tissue, to spatial transcriptomics of single cells and artificial intelligence-based image analysis have been utilized to better characterize the immune microenvironment in melanoma to provide novel predictive and prognostic biomarkers. In this review, we will highlight the different techniques currently under investigation for the detection of prognostic and predictive immune biomarkers in melanoma.

Circulating Tumor DNA: A Promising Biomarker for Predicting Recurrence in Patients with BRAF-Negative Melanoma

For patients with BRAF wild-type stage III and IV melanoma, there is an urgent clinical need to identify prognostic biomarkers and biomarkers predictive of treatment response. Circulating tumor DNA (ctDNA) is emerging as a blood-based biomarker and has shown promising results for many cancers, including melanoma. The purpose of this study was to identify targetable, tumor-derived mutations in patient blood that may lead to treatment alternatives and improved outcomes for patients with BRAF-negative melanoma. Using a CAncer Personalized Profiling by deep Sequencing (CAPP-seq) pan-cancer gene panel, ctDNA from 150 plasma samples (n = 106 patients) was assessed, including serial blood collections for a subset of patients (n = 16). ctDNA variants were detected in 85% of patients, all in targetable pathways, such as vascular endothelial growth factor receptor, epidermal growth factor receptor, phosphatidylinositol 3-kinase/AKT, Bcl2/mammalian target of rapamycin (mTOR), ALK/MET, and cyclin-dependent kinase 4/6. Patients with stage IV melanoma with low ctDNA concentrations, <10 ng/mL, had significantly better disease-specific survival and progression-free survival. Patients with both a high concentration of ctDNA and any detectable ctDNA variants had the worst prognosis. In addition, these results indicated that longitudinal changes in ctDNA correlated with treatment response and disease progression determined by radiology. This study confirms that ctDNA may be used as a noninvasive liquid biopsy to identify recurrent disease and detect targetable variants in patients with late-stage melanoma.

Case Report: Stereotactic body radiation treatment for immunotherapy escaped oligometastatic progression in cutaneous melanoma and merkel cell carcinoma

Oligometastatic progression represents a unique manifestation of tumor immune-escape that can lead to disease progression during treatment with immune checkpoint inhibitor (ICI). The diagnosis and further optimal management of oligometastatic progression through ICI remains unclear. Diagnostic challenges include practical limitations due to the anatomical sites of oligometastatic progression, such as the para-aortic region, where traditional tissue biopsy carries high risk, and circulating-tumor DNA (ctDNA) could aid in diagnosis and disease monitoring as a supplement to surveillance imaging. In this report, we describe two cases of one patient with metastatic melanoma and the other with metastatic Merkel cell carcinoma (MCC) who were treated with ICI and later developed localized resistance due to oligometastatic progression. We further highlight our experience using stereotactic body radiation therapy (SBRT) as a salvage approach to treat the oligometastatic progression. In addition, we describe the temporal and dynamic relationship of circulating-tumor DNA (ctDNA) prior to, during and after SBRT, which highly suggested the diagnosis without obtaining a histological specimen. Our cases highlight a potential role for SBRT in the management of oligometastatic progression. However, large prospective trials are essential to confirm the utility of this approach.

Private Payer and Medicare Coverage Policies for Use of Circulating Tumor DNA Tests in Cancer Diagnostics and Treatment

BACKGROUND

Circulating tumor DNA (ctDNA) is used to select initial targeted therapy, identify mechanisms of therapeutic resistance, and measure minimal residual disease (MRD) after treatment. Our objective was to review private and Medicare coverage policies for ctDNA testing.

METHODS

Policy Reporter was used to identify coverage policies (as of February 2022) from private payers and Medicare Local Coverage Determinations (LCDs) for ctDNA tests. We abstracted data regarding policy existence, ctDNA test coverage, cancer types covered, and clinical indications. Descriptive analyses were performed by payer, clinical indication, and cancer type.

RESULTS

A total of 71 of 1,066 total policies met study inclusion criteria, of which 57 were private policies and 14 were Medicare LCDs; 70% of private policies and 100% of Medicare LCDs covered at least one indication. Among 57 private policies, 89% specified a policy for at least 1 clinical indication, with coverage for ctDNA for initial treatment selection most common (69%). Of 40 policies addressing progression, coverage was provided 28% of the time, and of 20 policies addressing MRD, coverage was provided 65% of the time. Non-small cell lung cancer (NSCLC) was the cancer type most frequently covered for initial treatment (47%) and progression (60%). Among policies with ctDNA coverage, coverage was restricted to patients without available tissue or in whom biopsy was contraindicated in 91% of policies. MRD was commonly covered for hematologic malignancies (30%) and NSCLC (25%). Of the 14 Medicare LCD policies, 64% provided coverage for initial treatment selection and progression, and 36% for MRD.

CONCLUSIONS

Some private payers and Medicare LCDs provide coverage for ctDNA testing. Private payers frequently cover testing for initial treatment, especially for NSCLC, when tissue is insufficient or biopsy is contraindicated. Coverage remains variable across payers, clinical indications, and cancer types despite inclusion in clinical guidelines, which could impact delivery of effective cancer care.

Tebentafusp: a first-in-class treatment for metastatic uveal melanoma

Tebentafusp is a first-in-class immunotherapy agent that comprises an engineered T-cell receptor targeting a gp100 epitope presented by human leukocyte antigen-A*02:01 cells, fused to an anti-CD3 single-chain variable fragment. Tebentafusp is both the first bispecific T-cell engager to show efficacy in the treatment of advanced solid cancer and the first anti-cancer treatment to demonstrate an overall survival benefit in patients with uveal melanoma (UM). This review article will focus on the clinical development of tebentafusp, the mechanism of action and resultant evolution of the management of advanced UM.

Case report: Real-world experience using a personalized cancer-specific circulating tumor DNA assay in different metastatic melanoma scenarios

Circulating-tumor DNA (ctDNA) has emerged as an important biomarker for monitoring disease status in cancer patients. Different ctDNA testing platforms have shown promising results in the early detection of disease, monitoring response to treatment, and prognostication in metastatic melanoma. However, several challenges exist, including the reduced shedding of ctDNA into the bloodstream in the metastatic setting, differences in sensitivity among various ctDNA assays, and the inherent inability to distinguish tumor-specific mutations from other mutations that are not related to the cancer of interest. Using a ctDNA assay that is designed to detect multiple single-nucleotide variants (SNVs) that are specific to the tumor itself may allow for more accurate monitoring of disease status in metastatic melanoma. In this case series, we describe a real-world experience using a personalized, tumor-informed ctDNA assay to monitor the clinical trajectories of four patients with metastatic melanoma. Our report highlights potential benefits and limitations using ctDNA in this setting to inform clinical decision-making. This report provides a proof of concept of the technique using an mPCR-NGS-based ctDNA assay (Signatera TM) in the clinical context and in adjunct with other radiological information. Large cohort prospective trials would be needed to validate the utility and validity of this approach.

Circulating tumour DNA monitoring and early treatment for relapse: views from patients with early-stage melanoma

BACKGROUND

Circulating tumour DNA (ctDNA) monitoring is a new technology that detects cancer DNA fragments in blood circulation. Regular monitoring with ctDNA has the potential to detect and treat cancer relapse earlier, but there is little evidence on patient acceptability. This study examines the views of patients with early-stage melanoma on the acceptability of the test and early treatment.

METHODS

A qualitative cross-sectional design using one-to-one semi-structured telephone interviews was employed. Twenty-five patients diagnosed with early-stage melanoma (Stage IA-IIC) were asked for their views on ctDNA monitoring and early treatment for relapse. Interviews were analysed using reflexive thematic analysis.

RESULTS

Two themes were generated: ctDNA monitoring would add service value where participants described regular ctDNA monitoring in follow-up care as more reassuring, more "scientific" than skin checks and preferable to scans. Test results provide opportunity and knowledge focuses on how participants wanted to know when to expect results to manage anxiety, with a positive result seen as an opportunity to receive treatment early.

CONCLUSIONS

Participants were positive about ctDNA monitoring and early treatment and would welcome extra surveillance, as well as trust ctDNA tests. This indicates the feasibility of the wider implementation of ctDNA tests, which have applicability for many tumour types and disease stages.