Why do we still process pathology tissue like it's the 1800s?

The use of formalin fixation for pathology specimens was first described in the mid 1890s by these two guys and became the dominate method for tissue fixation in the early 1950s, prior to the discovery of DNA. While formalin-based tissue processing preserves tissue architecture allowing for morphologic evaluation and immunohistochemical staining, formalin-fixation and tissue processing causes extensive DNA-cross linking which results in fragmented DNA. Low quality DNA from formalin-fixed paraffin-embedded tissue is problematic for the genomic evaluation of clinical cancer specimens and is particularly challenging #WGS. In theory frozen cancer tissue is the ideal substrate for genomic testing, however, outside of specialized clinical trials, cold chain logistics from O.R. to lab are just too complicated and too expensive for routine clinical care.

Processing of pathology specimens needs to move in to the genomic era. To this end, I am pleased to announce that Dr. David Spencer and I have been awarded an IMAT R33 grant through the NIH to improve WGS methods for use in the molecular evaluation of lung cancer. As part of this grant we will explore different fixation and tissue processing methods that are compatible with both histologic and molecular pathology workflows. Very excited to start working on this project.

#genomics #dnasequencing #ngs