Molecular alterations in endometrial archived liquid‐based cytology

Abstract

Endometrial cancer is one of the most common gynecological malignancy worldwide and its prevalence is increasing. The introduction of liquid-based cytology (LBC) and endoflower dispositive in routine practice gives the possibility to examine endometrial cells by cytological diagnosis and may also release the opportunity to study molecular alterations, in endometrioid type cancer in which carcinogenesis is well known. We gathered 72 cases of endometrial LBC samples and corresponding formalin-fixed paraffin-embedded (FFPE) blocks, collected from 2004 to 2010. DNA was isolated from both samples using standard protocols. DNA quality and quantity were assessed using Nanodrop and BIOMED2 multiplex PCR. Mutations in exon 5 of PTEN and exon 20 of PI3K were studied using Sanger sequencing. DNA with good quality and amount was isolated from 67/72 FFPE cases. In these samples, two cases were found to harbor mutations in exon 5 of PTEN. No PI3K mutations were identified. LBC samples were then assessed to verify the concordance with the FFPE DNA results. The results obtained were concordant, that is the wild type cases in FFPE were also wild type in LBC and vice versa for the mutated case. Unfortunately, the second case of mutation in PTEN could not be confirmed in LBC due to low amount of DNA obtained. Detection of molecular alterations in LBC will open a new era for the detection in asymptomatic women of precursor lesions that could evolve into cancer and for endometrial cancer diagnosis and screening in selected high-risk women.