Molecular testing in salivary gland cytopathology: A practical overview in conjunction with the Milan system

Abstract

Recently, significant advances in the molecular characterization of salivary gland neoplasms have facilitated the classification and diagnosis of specific diagnostic entities. In the highly challenging diagnostic scenario of salivary malignancies, molecular testing is increasingly being adopted in routine practice to refine the cytological diagnosis of salivary lesions. Here, we reviewed the most recent evidence in the field of salivary glands molecular cytopathology.

Is molecular testing of salivary gland FNA specimens ready for prime time?

“…2 Over the last decade, significant advances have been made in the molecular characterization of salivary gland neoplasms. [3][4][5] Currently, most salivary gland neoplasms including newer entities are characterized by specific genetic alterations, mainly gene fusions that can be used for diagnostic purposes and sometimes therapeutic purposes. [3][4][5] Furthermore, additional genetic alterations including novel fusions and partners keep being identified, increasing the overall prevalence of genetic alterations across salivary gland neoplasms.…”

“…[3][4][5] Currently, most salivary gland neoplasms including newer entities are characterized by specific genetic alterations, mainly gene fusions that can be used for diagnostic purposes and sometimes therapeutic purposes. [3][4][5] Furthermore, additional genetic alterations including novel fusions and partners keep being identified, increasing the overall prevalence of genetic alterations across salivary gland neoplasms. Accordingly, there are several ancillary diagnostic tools at our disposal including IHC, fluorescent in situ hybridization (FISH), and more recently next-generation sequencing (NGS) technologies, which can all be successfully applied to FNA specimens, provided there is adequate material to do so.…”

“…1,[6][7][8][9][10] Over the last few years, some institutions have developed their own comprehensive customizable NGS with broad panels specifically designed to cover most gene alterations, including mutations, fusions ,and RNA gene expression alterations in salivary gland tumors. 3,12,14 Among them, the SalvGlandDx panel is an all-in-one RNA-based NGS panel for the detection of mutations, fusions and gene expression levels of 27 genes involved in salivary gland tumors. 3,14 The Sal-vGlandDx panel covers most of the common molecular alterations of salivary gland tumors in a single test and can be reliably performed on FFPE cell block specimens.…”

“…3,12,14 Among them, the SalvGlandDx panel is an all-in-one RNA-based NGS panel for the detection of mutations, fusions and gene expression levels of 27 genes involved in salivary gland tumors. 3,14 The Sal-vGlandDx panel covers most of the common molecular alterations of salivary gland tumors in a single test and can be reliably performed on FFPE cell block specimens. 3,14 Cancer Cytopathol.…”

“…3,14 The Sal-vGlandDx panel covers most of the common molecular alterations of salivary gland tumors in a single test and can be reliably performed on FFPE cell block specimens. 3,14 Cancer Cytopathol. 2024;132:393-395.…”