Wednesday, July 19, 2023

AI Corner: Using ChatGPT to Assess a New Review Article on ctDNA [Cohen 2023]

Nature publishes an important new review article on ctDNA on July 12, 2023.  The article is Cohen, Liu, and Aleshin, "Practical recommendations for using ctDNA in clinical decision making." Here.

Below, I copy the original abstract of the article.

Then, I give a summary generated in a few seconds by ChatGPT 3.5, and I ask ChatGPT several questions about the article and its implications.

As is usually the case when I give AI examples, the point for me is not so much "good" or "bad," but finding out what - what the technology looks like and feels like in its current state.

(I've done a very similar analysis to COHEN ctDNA, for RICHARDSON (radiology AI) and DEY (CV imaging). 



The continuous improvement in cancer care over the past decade has led to a gradual decrease in cancer-related deaths. This is largely attributed to improved treatment and disease management strategies. Early detection of recurrence using blood-based biomarkers such as circulating tumour DNA (ctDNA) is being increasingly used in clinical practice. Emerging real-world data shows the utility of ctDNA in detecting molecular residual disease and in treatment-response monitoring, helping clinicians to optimize treatment and surveillance strategies. Many studies have indicated ctDNA to be a sensitive and specific biomarker for recurrence. However, most of these studies are largely observational or anecdotal in nature, and peer-reviewed data regarding the use of ctDNA are mainly indication-specific. Here we provide general recommendations on the clinical utility of ctDNA and how to interpret ctDNA analysis in different treatment settings, especially in patients with solid tumours. Specifically, we provide an understanding around the implications, strengths and limitations of this novel biomarker and how to best apply the results in clinical practice.


From here out, all the text is AI generated, except my questions.  I submitted the 6000 word article to ChatGPT in 3 parts using a splitter.


Please summarize this article in detail including key points, for a biomedical reader who does not have time to read the whole article but needs a good idea of all the main points.



This article discusses the clinical utility of circulating tumor DNA (ctDNA) testing in the management of solid tumors, focusing on colorectal, breast, lung, and bladder cancers, as well as immunotherapy-treated cancers. ctDNA testing involves the detection and analysis of tumor-derived genetic material in the bloodstream and has shown promise as a prognostic and predictive biomarker.

The article highlights key applications of ctDNA testing at different stages of cancer management:

  • Baseline Measurement: ctDNA testing before treatment can help stratify patients based on their risk of recurrence and inform treatment decisions. Positive ctDNA status after surgery indicates a higher risk of recurrence and may guide the use of adjuvant chemotherapy.
  • Minimal Residual Disease (MRD) Monitoring: Serial testing of ctDNA during follow-up allows for the early detection of disease recurrence and helps improve the sensitivity of the assay. Dynamic changes in ctDNA levels following treatment can indicate treatment response or primary resistance, guiding the need for adjuvant therapy or the completion of treatment.
  • Timing of Blood Draw: It is recommended to wait for at least two weeks post-surgery before drawing the initial blood sample for ctDNA-based MRD testing to overcome potential confounding factors such as surgical trauma-induced cfDNA increase. Short interval follow-up draws can confirm negative results and allow timely initiation of adjuvant treatment if necessary.

The article also emphasizes the clinical accuracy of ctDNA testing in detecting disease recurrence across various solid tumors, including colorectal, breast, bladder, lung, and pancreatic cancers. ctDNA-based MRD detection has shown high sensitivity and specificity, leading to improved surveillance strategies and earlier detection of recurrence compared to standard imaging-based methods.

Management strategies for ctDNA-positive patients involve adjuvant systemic therapy, while ctDNA-negative patients may benefit from de-escalation or omission of therapy based on risk assessment. Longitudinal monitoring of ctDNA provides valuable information on treatment response, neoadjuvant therapy effectiveness, and exceptional responders.

Furthermore, ctDNA monitoring aids in distinguishing pseudoprogression from true progression, potentially guiding treatment decisions and avoiding premature treatment discontinuation or unnecessary therapies. It may also help identify hyperprogression and exceptional responders. Immune-related adverse events (IRAEs) can be monitored using ctDNA, assisting in determining the continuation or cessation of immunotherapy.

While ctDNA testing holds great potential, the article highlights the need for further prospective studies and clinical trials to validate its clinical utility and define standardized approaches for different cancer types and treatment settings. As the field advances, ctDNA testing is likely to be incorporated into routine clinical practice to supplement or even replace current standard metrics.

Key Points:

  • ctDNA testing has clinical utility in managing solid tumors, aiding in risk stratification, treatment decisions, and surveillance.
  • Serial testing improves ctDNA assay sensitivity and detects disease recurrence earlier.
  • Dynamic changes in ctDNA levels indicate treatment response or primary resistance.
  • Timing of blood draw relative to surgery is important to avoid confounding factors.
  • ctDNA testing shows high accuracy in detecting recurrence across multiple solid tumor types.
  • ctDNA-based MRD detection can guide adjuvant therapy decisions.
  • Longitudinal ctDNA monitoring assists in neoadjuvant therapy assessment and identifies exceptional responders.
  • ctDNA testing helps differentiate pseudoprogression from true progression in immunotherapy-treated cancers.
  • ctDNA monitoring may identify hyperprogression and guide treatment decisions for immune-related adverse events.
  • Prospective studies are needed to further validate ctDNA's clinical utility and define standardized approaches.

Please note that this summary provides an overview of the main points discussed in the article, but it is always recommended to refer to the original source for comprehensive details and specific context.

What are some of the concerns and risks in this area of oncology?  

Where could the harms exceed the benefits?


While ctDNA testing holds promise in the field of oncology, there are several concerns and potential risks that need to be considered. Here are some areas where the harms could potentially exceed the benefits:

  • False Positive and False Negative Results: ctDNA testing may yield false positive or false negative results, leading to misinterpretation and potentially inappropriate treatment decisions. False positives may result in unnecessary interventions and overtreatment, while false negatives may lead to delayed or missed detection of disease recurrence.
  • Technical Limitations: Different ctDNA assay platforms may have varying sensitivity and specificity, and the performance characteristics of each assay should be carefully evaluated. Technical limitations, including assay variability, inter-laboratory variability, and the potential for false results due to low ctDNA levels, can impact the accuracy and reliability of ctDNA testing.
  • Lack of Standardization: There is currently a lack of standardized protocols and guidelines for ctDNA testing, including pre-analytical, analytical, and post-analytical aspects. Standardization is crucial to ensure consistent and reliable results across different laboratories and to enable meaningful comparisons between studies.
  • Clinical Validation: While retrospective studies have shown promising results, larger prospective studies and clinical trials are needed to validate the clinical utility of ctDNA testing. Robust evidence is required to establish the impact of ctDNA-based decisions on patient outcomes and survival.
  • Cost and Accessibility: ctDNA testing may be costly and may not be widely accessible, potentially limiting its widespread implementation in clinical practice. The availability and cost-effectiveness of ctDNA assays need to be considered to ensure equitable access for patients.
  • Ethical and Psychological Considerations: The introduction of ctDNA testing raises ethical considerations, including informed consent, privacy, and the potential psychological impact of test results on patients and their families. The potential for anxiety, uncertainty, and psychological distress related to ctDNA testing should be carefully addressed.
  • Overdiagnosis and Overtreatment: The sensitive nature of ctDNA testing may lead to the detection of minimal residual disease or subclinical disease that may not progress or impact patient outcomes. Overdiagnosis and subsequent overtreatment could expose patients to unnecessary interventions, adverse effects, and psychological burden.
  • Unproven Impact on Survival: While ctDNA testing has shown promise as a prognostic and predictive tool, its impact on long-term survival outcomes, such as overall survival or disease-free survival, needs further investigation. Clear evidence demonstrating improved patient outcomes is essential before widespread implementation.

It is important to recognize that the concerns and risks associated with ctDNA testing are areas of active research and development. Addressing these challenges through ongoing studies, standardization efforts, and robust validation will be crucial to maximize the benefits of ctDNA testing while minimizing potential harms.

What is the most groundbreaking or surprising aspect (or a couple aspects) of the technology in this article?


The article highlights several groundbreaking aspects of ctDNA technology in the field of oncology. Here are a couple of the most notable aspects:

  1. Early Detection of Minimal Residual Disease (MRD): One groundbreaking aspect of ctDNA technology is its ability to detect minimal residual disease, which refers to the presence of residual cancer cells after primary treatment, such as surgery or chemotherapy. By detecting and monitoring ctDNA levels, clinicians can assess the effectiveness of treatment and detect disease recurrence at an early stage. The article emphasizes that ctDNA testing can provide a highly significant prognostic factor, surpassing other clinicopathological risk factors. This capability has the potential to revolutionize post-treatment surveillance and allow for timely intervention to prevent disease progression.
  2. Treatment Response Monitoring: ctDNA testing offers a powerful tool for monitoring treatment response in cancer patients. By analyzing changes in ctDNA levels over time, clinicians can assess the effectiveness of therapy and make informed decisions regarding treatment adjustments. The article highlights that ctDNA clearance is associated with a favorable prognosis, indicating a positive treatment response. Conversely, persistent or increasing ctDNA levels suggest primary resistance to therapy or disease recurrence. This real-time monitoring of treatment response can help optimize treatment strategies and potentially lead to improved patient outcomes.
  3. Personalized Treatment Decisions: Another groundbreaking aspect of ctDNA technology is its potential to guide personalized treatment decisions. The ability to detect specific genetic alterations and mutations in ctDNA allows for the identification of targeted therapies and the monitoring of treatment efficacy. This approach can help tailor treatment regimens to individual patients, maximizing the likelihood of therapeutic success while minimizing unnecessary interventions. The article highlights that ctDNA testing may inform decisions regarding adjuvant therapy, de-escalation or intensification of treatment, and the selection of alternative therapies in cases of primary resistance or treatment failure.
  4. Immunotherapy Response Assessment: ctDNA testing shows promise in assessing treatment response and predicting outcomes in patients receiving immune checkpoint blockade therapy. It can help distinguish between true progression, pseudoprogression (initial radiographic tumor growth followed by regression due to immune response), and hyperprogression (accelerated tumor growth under immunotherapy). This capability is crucial for guiding treatment decisions, avoiding premature discontinuation of effective therapy, and identifying patients who may benefit from alternative treatments.

These groundbreaking aspects of ctDNA technology have the potential to transform cancer management by enabling early detection, personalized treatment approaches, and real-time monitoring of treatment response. Further research, validation, and standardization are necessary to fully harness the clinical potential of ctDNA testing across various cancer types and treatment modalities.


Can these four points be considered breakthroughs?  Or just ideas with "potential?"


These four points can be considered as significant breakthroughs in the field of oncology. While further research and validation are necessary to fully establish their clinical utility and standardize their use, the current evidence and potential applications of ctDNA technology represent major advancements in cancer management. Here's a closer look at why these points can be considered breakthroughs:

  1. Early Detection of Minimal Residual Disease (MRD): The ability of ctDNA technology to detect minimal residual disease and monitor disease recurrence at an early stage is a significant breakthrough. Traditionally, recurrence or metastasis detection relied on imaging or biomarkers, which may not be sensitive enough to detect microscopic residual disease. ctDNA testing offers a more sensitive and specific approach for early detection, enabling timely intervention and potentially improving patient outcomes.
  2. Treatment Response Monitoring: ctDNA technology's capability to monitor treatment response in real time is groundbreaking. It allows clinicians to assess the effectiveness of therapy and make informed decisions regarding treatment adjustments, such as dose modifications or changes in treatment regimens. This personalized approach to treatment monitoring has the potential to optimize patient care and improve treatment outcomes.
  3. Personalized Treatment Decisions: The ability to detect specific genetic alterations and mutations in ctDNA and use this information to guide personalized treatment decisions represents a significant breakthrough. ctDNA testing enables the identification of targeted therapies and helps tailor treatment regimens to individual patients based on their specific molecular profiles. This personalized treatment approach holds promise for maximizing treatment efficacy while minimizing unnecessary interventions and potential side effects.
  4. Immunotherapy Response Assessment: ctDNA technology's potential to assess treatment response and predict outcomes in patients receiving immune checkpoint blockade therapy is groundbreaking. Immune-related responses, such as pseudoprogression and hyperprogression, can be challenging to identify using conventional imaging techniques. ctDNA testing provides a molecular-level assessment of treatment response, allowing for more accurate identification of these responses and informed decision-making regarding treatment continuation or alternative therapies.

While further research and validation are needed to fully establish the clinical utility and widespread adoption of ctDNA technology, the current evidence and potential applications of these breakthroughs have the potential to revolutionize cancer management and improve patient care.

What would accelerate adoption in this field?  

Conversely, what would slow it down?


Several factors can accelerate the adoption of ctDNA technology in the field of oncology, while certain challenges may slow down its implementation. Here are some key factors that can affect the pace of adoption:

Factors that could accelerate adoption:

  • Robust Clinical Validation: Conducting large-scale, prospective clinical studies that provide strong evidence of ctDNA's clinical utility and its impact on patient outcomes would significantly accelerate adoption. Well-designed trials with clear endpoints, standardized protocols, and rigorous validation of ctDNA assays can establish its reliability, sensitivity, and specificity across different cancer types and stages.
  • Standardized Assays and Protocols: Developing standardized assays and protocols for ctDNA analysis would facilitate its adoption. Consistent methodologies, quality control measures, and standardized reporting frameworks would enhance reproducibility and comparability across different laboratories and institutions. This would increase confidence among clinicians and regulatory bodies regarding the reliability and accuracy of ctDNA results.
  • Cost-Effectiveness and Accessibility: Ensuring that ctDNA testing becomes cost-effective and widely accessible would promote its adoption. The affordability and availability of ctDNA assays, along with streamlined workflows and efficient turnaround times, would enable broader integration into routine clinical practice. Reducing the financial burden on patients and healthcare systems would be crucial for widespread adoption.
  • Education and Training: Providing education and training programs to healthcare professionals regarding the principles, interpretation, and clinical applications of ctDNA technology would accelerate adoption. Enhancing the understanding of ctDNA testing among oncologists, pathologists, and other relevant specialists would promote its appropriate utilization and interpretation, leading to increased confidence in incorporating ctDNA testing into clinical decision-making.

Factors that could slow down adoption:

  • Limited Clinical Evidence: Insufficient high-quality clinical evidence supporting the clinical utility and impact of ctDNA testing could slow down its adoption. Robust studies demonstrating the benefits of ctDNA technology, including improved patient outcomes and cost-effectiveness, are crucial to convince clinicians, healthcare institutions, and regulatory authorities of its value.
  • Complex Data Interpretation: The interpretation of ctDNA results can be complex, requiring expertise in molecular biology and genetics. The complexity of data analysis, variant interpretation, and integration into clinical decision-making may pose a challenge. Developing user-friendly bioinformatics tools and decision support systems that aid in data interpretation and reporting could help overcome this barrier.
  • Regulatory and Reimbursement Challenges: Regulatory approvals and reimbursement policies play a vital role in the adoption of novel technologies. Delays or uncertainties in regulatory clearance or reimbursement coverage for ctDNA assays could impede widespread implementation. Establishing clear guidelines, regulatory frameworks, and reimbursement mechanisms that accommodate ctDNA testing would be essential.
  • Infrastructure and Resource Limitations: Implementing ctDNA technology may require significant infrastructure and resource investments. Laboratories need specialized equipment, trained personnel, and adequate bioinformatics capabilities to handle and analyze ctDNA samples. Limited resources, particularly in smaller healthcare settings, could hinder the adoption of ctDNA technology.

Addressing these challenges through collaborative efforts among researchers, healthcare providers, policymakers, and industry stakeholders will be crucial for accelerating the adoption of ctDNA technology in clinical practice. Continued research, standardization, education, and supportive policies can help overcome these barriers and facilitate the widespread integration of ctDNA testing into routine oncology care.


General a script for a two minute video about the article, where an expert who thoroughly understands the article and its content provides a brief video overview for other oncologists and researchers in ctDNA.


[Opening shot: A professional setting with a well-informed expert seated in front of a bookshelf filled with medical literature]

Expert: "Hello, fellow oncologists and researchers in ctDNA. Today, I would like to provide you with a brief overview of an exciting article that delves into the current landscape of ctDNA testing and its implications in oncology."

[Cut to visuals of key points from the article being highlighted]

Expert: "This article explores the potential of ctDNA, circulating tumor DNA, as a powerful tool in the field of oncology. It discusses how ctDNA testing can revolutionize cancer management, from early detection and diagnosis to treatment response monitoring and surveillance."

[Cut to visuals of a laboratory technician performing ctDNA analysis]

Expert: "One groundbreaking aspect highlighted in the article is the ability of ctDNA testing to detect minimal residual disease (MRD) with high sensitivity and specificity. This allows for the early identification of disease recurrence and the optimization of treatment strategies."

[Cut to visuals of a patient receiving personalized treatment based on ctDNA results]

Expert: "Another exciting development is the use of ctDNA as a predictive biomarker for treatment response. By monitoring dynamic changes in ctDNA levels, clinicians can assess the effectiveness of therapies and make informed decisions regarding treatment modifications."

[Cut to visuals of a research team discussing the potential of ctDNA]

Expert: "The article also emphasizes the importance of serial testing and the role it plays in improving the sensitivity of ctDNA assays. Serial monitoring enables the detection of disease recurrence at earlier stages, allowing for timely intervention and improved patient outcomes."

[Cut to visuals of oncologists and researchers discussing the article's findings]

Expert: "To accelerate the adoption of ctDNA testing in clinical practice, the article highlights the need for robust clinical validation, standardized assays, and cost-effectiveness. It also emphasizes the significance of education and training programs to enhance the understanding and interpretation of ctDNA results."

[Closing shot: Expert summarizing the main takeaway]

Expert: "In summary, this article showcases the tremendous potential of ctDNA testing in transforming the way we manage cancer. By harnessing the power of ctDNA, we can enhance early detection, personalize treatment approaches, and improve patient outcomes."

Expert: "I encourage you to read the full article to gain a comprehensive understanding of the advancements in ctDNA technology and its implications in oncology. Together, let's embrace this groundbreaking tool and shape the future of cancer care."

[Fade out with the expert's closing remarks and a call-to-action to read the full article]

Note: The script provided is a general outline for a two-minute video overview and can be modified or expanded upon to suit the specific requirements of the video production.


What do the authors mean, in the title, the article will be "practical" recommendations.  How would a reader be most impressed by the article being "practical?"  Do they achieve that (the authors?).


When the authors refer to the article providing "practical" recommendations, they are indicating that the content offers actionable guidance that can be implemented in real-world clinical settings. The emphasis on practicality suggests that the article goes beyond theoretical concepts and provides tangible suggestions and approaches for integrating ctDNA testing into routine oncology practice.

To impress readers with its practicality, the article should offer clear and concise recommendations that are directly applicable to their clinical work. The recommendations should address common challenges and provide solutions or strategies that can be readily implemented. Additionally, the article should consider the feasibility, scalability, and cost-effectiveness of incorporating ctDNA testing into existing healthcare systems.

Whether the authors achieve practicality depends on the specific content of the article. Readers would be most impressed if the article offers step-by-step guidelines, identifies potential barriers to implementation, provides evidence-based support for the recommendations, and includes case studies or examples that illustrate how the recommendations can be put into practice.

Overall, the practicality of the article can be evaluated based on its ability to empower readers with actionable insights and enable them to navigate the complexities of ctDNA testing in their clinical decision-making process.