Massively parallel DNA sequencing from routinely processed cytological smears.

ABSTRACT

BACKGROUND: Data generated by next-generation sequencing technologies have a pivotal role in precision medicine. These high-throughput techniques are preferentially performed on fresh tissue, but there is an increasing need for protocols adapted to materials derived from formalin-fixed, paraffin-embedded tissue and cytology specimens. METHODS: The aim of this work was to show that cytological material collected from archival smears processed for routine diagnoses could be used for massively parallel sequencing and array-based genomic analysis for further studies. RESULTS: As a proof of concept, data obtained from May-Grünwald Giemsa- and Diff-Quik-stained archival smears were shown to be in keeping with those obtained from matched frozen controls. CONCLUSIONS: The quality of DNA extracted from routinely processed smears is compatible with the multitargeted sequencing of a large series of genes of interest with methods such as array-based genomic analysis and whole-exome sequencing.