52 Recent advances in liquid biopsy technologies are transforming the landscape of Hodgkin lymphoma (HL) diagnosis and monitoring. A new study shows that liquid biopsies, especially those that find circulating tumour DNA (ctDNA), might be a better and less invasive way to check how well treatment is working and predict relapses in people with classical Hodgkin lymphoma (cHL). The findings were published in the Journal of Experimental & Clinical Cancer Research. Hodgkin lymphoma is a type of cancer primarily affecting adolescents and young adults, with the classical form (cHL) accounting for 90% of cases. The standard treatment for cHL typically includes chemotherapy and, in some cases, radiotherapy. Although these treatments are highly effective, curing approximately 80% of patients, they come with significant risks, particularly late toxic effects, which are the leading cause of death in cHL survivors. The most commonly used tool for monitoring treatment response in cHL has been positron emission tomography/computed tomography (PET/CT). While PET/CT scans are valuable, they have limitations, such as high false-positive rates and the risk of long-term radiation exposure. This underscores the urgent need for more reliable and less invasive methods to monitor disease progression and treatment response. Liquid biopsy, a non-invasive technique that analyses biofluids like blood for cancer-related genetic material, is emerging as a promising alternative. It offers several advantages over traditional tissue biopsies and imaging methods, such as ease of sampling and the ability to monitor patients more frequently. The study under review particularly emphasises the role of ctDNA in cHL. ctDNA, fragments of DNA shed from tumours into the bloodstream, can be detected and analysed to provide insights into the genetic mutations driving the disease. This approach not only aids in diagnosing the cancer but also in monitoring how well a patient is responding to treatment and predicting potential relapses. The study highlights several key findings regarding the use of ctDNA in cHL. Researchers have discovered a strong correlation between ctDNA levels and the PET/CT scan-measured tumor burden. Moreover, a significant reduction in ctDNA levels after the initial cycles of chemotherapy was associated with a better prognosis, indicating that ctDNA could serve as an early marker of treatment success. Another critical discovery is the ability of ctDNA to predict relapses before they are clinically evident. This is particularly important in cHL, where early detection of relapse could lead to timely intervention and potentially better outcomes for patients. The study demonstrates that ctDNA analysis could achieve this with higher sensitivity compared to traditional methods, offering a glimpse into the future of personalised cancer care. While the use of ctDNA in cHL is still in the early stages of research, the findings of this study suggest that it has significant potential to improve patient management. As the technology evolves, ctDNA could become a standard tool not only for monitoring treatment response but also for refining risk stratification and guiding treatment decisions. But the implementation of ctDNA analysis in clinical practice faces several challenges. These include the need for standardised protocols for sample collection and analysis, as well as the development of highly sensitive and specific assays that can detect ctDNA at very low levels. Moreover, integrating ctDNA testing with existing diagnostic and monitoring tools will require careful consideration to ensure it enhances, rather than complicates, patient care.