Abstract P2-05-07: Feasibility and sensitivity of fine-needle aspiration biopsies for the detection of somatic mutations using next-generation sequencing in breast cancer

Background/Purpose: Next-generation sequencing (NGS) is being incorporated rapidly into clinical practice. Fine-needle aspiration biopsy (FNAB) specimens have been used feasibly in molecular analysis including direct sequencing and microarrays. They are readily available and enriched in malignant cells, thus providing opportunities for genomic analysis for more clinical samples. In this study, we assessed the feasibility and sensitivity of FNAB for the detection of somatic mutations by NGS compared to bulk tissue. Methods: Bulk tissue and FNAB was sampled via skin superficial to the palpable tumor from surgically resected breast cancer specimen. DNA was extracted from the bulk tissues and FNAB samples obtained from twelve patients. Somatic mutations detected from whole exome sequencing (WES) by next-generation sequencing (NGS) (HiSeq 2500, Illumina) were analyzed for corresponding pairs of bulk tissue and FNAB. Verification of somatic mutations detected exclusively from FNAB and known to be clinically relevant to breast cancer was carried out by Sanger sequencing. Invasive tumor percentages of bulk tissues were evaluated using hematoxylin and eosin (HE San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P2-05-07.