FOXL2 p.C134W mutational analysis for juvenile/adult granulosa-cell tumour of ovary

Molecular Pathology

Background

Adult-type granulosa cell tumours of the ovary (aGCTs) are rare tumours that represent 2–5% of ovarian malignancies. The prognosis of this tumour is favourable, and it is characterized by slow progression. 10–30% of these tumours recur after 4–7 years of the primary surgery and the 5-year survival rate from the first recurrence is 55%, for the incompletely resected patients. Heterozygous point mutation of c.402C>G in the FOXL2 gene can be found in 97% of cases of aGCT.

Purpose of test

The test identifies the specific FOXL2 point mutation c.402C>G p.Cys134Trp (p.C134W) by Sanger sequencing.

Expected test result

FOXL2 c.402C>G mutation detected/not detected.

Caveats

DNA integrity and concentration must meet assay requirements. Low tumour content (<50%) may result in a false negative result.

Proficiency testing

Alternative performance assessment programme.

References

1.Schrader KA et al The specificity of the FOXL2 c.402C>G somatic mutation: a survey of solid tumors PLoS One. 2009 Nov 24;4(11):e7988

2.Kommoss S et al FOXL2 molecular testing in ovarian neoplasms: diagnostic approach and procedural guidelines. Mod Pathol. 2013 Jun;26(6):860-7

3.Shah SP et al Mutation of FOXL2 in granulosa-cell tumors of the ovary. N Engl J Med. 2009 Jun 25;360(26):2719-29