A current perspective on the pathological assessment of FOXL2 in adult‐type granulosa cell tumours of the ovary. Issue 3 (6th November 2013)

• Record Type: Journal Article
• Authors: Kommoss, Stefan; Gilks, Cyril Blake; Penzel, Roland; Herpel, Esther; Mackenzie, Robertson; Huntsman, David; Schirmacher, Peter; Anglesio, Michael; Schmidt, Dietmar; Kommoss, Friedrich
• Is Part Of: Histopathology. Volume 64:Issue 3(2014)
• Page Start: 380
• Page End: 388
• Publication Date: 2013-11-06
• Subjects: Histology, Pathological -- Periodicals; 611.018
• DOI: 10.1111/his.12253
• Languages: English
• ISSNs: 0309-0167

Abstract

<abstract abstract-type="main" id="his12253-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="his12253-sec-0001" sec-type="section"> <title>Aims</title> <p>The diagnosis of adult‐type granulosa cell tumours of the ovary (aGCT) is based on histomorphology aided by immunohistochemical staining for sex cord markers. Recently a single, recurrent somatic point mutation (402C→G) in <italic>FOXL2</italic> was described in aGCT. We have investigated the impact of <italic>FOXL2</italic> mutation testing in a large cohort of aGCT diagnosed previously by conventional histology and immunohistochemistry.</p> </sec> <sec id="his12253-sec-0002" sec-type="section"> <title>Methods and results</title> <p>Formalin‐fixed, paraffin‐embedded tissue cores from a cohort of 52 aGCT diagnosed previously by expert gynaecopathologists were analysed immunohistologically. <italic>FOXL2</italic> mutation status was determined by Sanger sequencing and high‐sensitivity TaqMan allelic discrimination assay. Histomorphology was reassessed by two expert gynaecopathologists. <italic>FOXL2</italic> mutation analyses could be performed successfully in 46 cases, 40 of which were positive for the c.402C>G mutation, confirming a diagnosis of aGCT. In the six cases negative for the c.402C>G mutation, one case was confirmed on review as <italic>FOXL2</italic> wild‐type aGCT, whereas in the remaining five cases diagnoses other than aGCT were made.</p> </sec> <sec id="his12253-sec-0003" sec-type="section"> <title>Conclusion</title> <p>In cases where a diagnosis of aGCT is a consideration and unequivocal diagnosis is not possible based on morphology and routine immunostains, <italic>FOXL2</italic> mutation testing can help to confirm the diagnosis. It is particularly relevant for accurate subclassification within the group of sex cord–stromal tumours.</p> </sec> </abstract>