Detection of TP53 and PIK3CA Mutations in Circulating Tumor DNA Using Next-Generation Sequencing in the Screening Process for Early Breast Cancer Diagnosis.

Rodriguez BJ1,2, Córdoba GD3, Aranda AG2, Álvarez M2, Vicioso L4, Pérez CL1,2, Hernando C5, Bermejo B5,6, Parreño AJ5, Lluch A6,7, Ryder MB8, Jones FS8, Fredebohm J8, Holtrup F8, Queipo-Ortuño MI9,10, Alba E1,2,6.

Author information

1: Unidad de Gestión Clínica Intercentros de Oncología Medica, Hospitales Universitarios Regional y Virgen de la Victoria de Málaga, 29010 Málaga, Spain.
2: Instituto de Investigación Biomédica de Málaga (IBIMA)-CIMES-UMA, 29010 Málaga, Spain.
3: Radiology Department, Hospital Clínico Universitario Virgen de la Victoria de Málaga, 29010 Málaga, Spain.
4: Histopathology Department, Hospital Clínico Universitario Virgen de la Victoria de Málaga, 29010 Málaga, Spain.
5: Hospital Clínico de Valencia, Instituto de Investigación Sanitaria INCLIVA, 46010 Valencia, Spain.
6: Centro de Investigacion Biomedica en Red Cancer (CIBERONC), 28029 Madrid, Spain.
7: Hospital Clínico de Valencia, Universidad de Valencia, Instituto de Investigación Sanitaria INCLIVA, 46010 Valencia, Spain.
8: Sysmex Inostics, GmbH, 20251 Hamburg, Germany.
9: Unidad de Gestión Clínica Intercentros de Oncología Medica, Hospitales Universitarios Regional y Virgen de la Victoria de Málaga, 29010 Málaga, Spain. maribelqo@gmail.com.
10: Instituto de Investigación Biomédica de Málaga (IBIMA)-CIMES-UMA, 29010 Málaga, Spain. maribelqo@gmail.com.

Abstract

Circulating tumor DNA (ctDNA) has emerged as a non-invasive "liquid biopsy" for early breast cancer diagnosis. We evaluated the suitability of ctDNA analysis in the diagnosis of early breast cancer after mammography findings, comparing PIK3CA and TP53 mutations between tumor biopsies and pre-biopsy circulating DNA. Matched plasma and frozen fresh tissue biopsies from patients with Breast Imaging-Reporting and Data System (BIRADS) 4c/5 mammography findings and subsequent diagnosis of primary breast cancer were analyzed using NGS TruSeq Custom Amplicon Low Input Panel (Illumina) and plasma SafeSEQ (Sysmex Inostics). The same plasma and tumor mutations were observed in eight of 29 patients (27.6%) with four in TP53 and five in PIK3CA mutations. Sequencing analysis also revealed four additional ctDNA mutations (three in TP53 and one in PIK3CA) previously not identified in three patients tissue biopsy. One of these patients had mutations in both genes. Age, tumor grade and size, immunohistochemical (IHC) subtype, BIRADS category, and lymph node positivity were significantly associated with the detectability of these blood tumor-derived mutations. In conclusion, ctDNA analysis could be used in early breast cancer diagnosis, providing critical clinical information to improve patient diagnosis.