Pre-analytical Factors Affecting ctDNA Analysis in Early and Locally Advanced Breast Cancer

This study evaluates pre-analytical factors affecting circulating tumor deoxyribonucleic acid (ctDNA) analysis in breast cancer that not spread beyond the breast and or lymph nodes (early and locally advanced). ctDNA refers to freely circulating tumor DNA fragments found in the blood plasma. Pre-analytical factors such as blood collection tubes, delays in separation of plasma, centrifugation speeds, storage conditions, shipping and DNA extraction methods can all affect ctDNA measurements. Inappropriate processing can cause breaking down of the membrane (lysis) of peripheral blood cells that release background wild-type DNA and may also cause degradation of circulating tumor-specific DNA fragments. Both mechanisms will dilute levels of ctDNA in plasma and make it more difficult to detect. Evaluating the pre-analytical factors of the collection of blood and left over tissue samples for the research of cancer may help researchers to evaluate the impact of the blood collection/processing and long-term storage from patients with locally advanced breast cancer.