The potential role of liquid biopsy in NHL and its current limitations

Following the International Congress on Malignant Lymphoma (15-ICML) in Lugano, Switzerland, Associate Professor Dipti Talaulikar, ANU College of Health & Medicine, Canberra, AU, discusses the potential role of liquid biopsy in non-Hodgkin lymphoma (NHL) with the Lymphoma Hub.

During the cell-free DNA (cfDNA) workshop at 15-ICML, the topic of bridging liquid biopsy in the management of lymphoma patients was addressed. This workshop covered the potential applications of liquid biopsy, and how this can be translated into clinical practice. Assoc. Prof. Talaulikar emphasizes that currently, it is challenging to obtain a biopsy from primary malignant tissue, indicating the prognostic value of liquid biopsy which uses easily-obtainable blood and plasma samples to extract DNA (or RNA) to allow for a genetic diagnosis of lymphoma.

Another application of liquid biopsy that is discussed is for post-treatment monitoring of responses by measuring minimal residual disease (MRD). Liquid biopsy prevents the impractical need to repeat standard biopsies, and the results can be combined with others, such as PET scan response assessment. Additionally, liquid biopsies provide a more accurate representation of spatial heterogeneity of lymphoma, allowing clinicians to determine if targeted therapy might be applicable.

However, the technique has some disadvantages including; the current lack of standardization in the field, the difficulty in obtaining adequate DNA/RNA from the sample, and the requirement to correctly protect the sample.
Assoc. Prof. Talaulikar also describes the NHL29 study; a phase II, single-arm study in elderly patients with diffuse large B-cell lymphoma, which is using next-generation sequencing on lymph node tissue, as well as analysis of cfDNA at diagnosis, specific time points during treatment and post-treatment.

Assoc. Prof. Talaulikar concluded that, in her opinion, the technique of liquid biopsy will simply translate into clinical practice as the method is easy to implement, even in resource-poor areas.