Strengths and Limitations of Tissue and Liquid Testing in Clinical Practice

Here the discussion turns to the operational and technical realities of tissue and liquid testing. The experts describe how tissue samples can provide deep and detailed molecular data but are often constrained by small sample size, poor quality, or long turnaround times. They explain how insufficient tissue can delay results and sometimes force repeat biopsies, which can be burdensome for patients. Liquid biopsy is presented as a powerful complement, offering a rapid and minimally invasive way to detect tumor DNA in the blood. However, the panel cautions that liquid testing can yield false negatives, especially in patients with low tumor burden or limited shedding of circulating tumor DNA. The clinicians explain how they counsel colleagues and patients about these limitations so that negative liquid results are interpreted appropriately. By comparing the two approaches, the panel shows how combining tissue and liquid testing can provide a more complete and timely molecular picture. This segment reinforces that understanding test limitations is just as important as knowing their strengths when making treatment decisions.