Sign in →

Test ID XL2T FOXL2 Mutations Analysis, Next-Generation Sequencing, Tumor

Necessary Information

A pathology report (final or preliminary), at minimum containing the following information, must accompany specimen for testing to be performed:

1. Patient name

2. Block number-must be on all blocks, slides, and paperwork (can be handwritten on the paperwork)

3. Tissue collection date

4. Source of the tissue

Specimen Required

This assay requires at least 20% tumor nuclei.

-Preferred amount of tumor area with sufficient percent tumor nuclei: tissue 216 mm(2)

-Minimum amount of tumor area: tissue 36 mm(2)

-These amounts are cumulative over up to 10 unstained slides and must have adequate percent tumor nuclei.

-Tissue fixation: 10% neutral buffered formalin, not decalcified

-For specimen preparation guidance, see Tissue Requirement for Solid Tumor Next-Generation Sequencing. In this document, the sizes are given as 4mm x 4mm x 10 slides as preferred: approximate/equivalent to 144 mm(2) and the minimum as 3mm x 1mm x 10 slides: approximate/equivalent to 36 mm(2).



Specimen Type: Tissue block

Collection Instructions: Submit a formalin-fixed, paraffin-embedded tissue block with acceptable amount of tumor tissue.



Specimen Type: Tissue slides

Slides: 1 Stained and 10 unstained

Collection Instructions: Submit 1 slide stained with hematoxylin and eosin and 10 unstained, nonbaked slides with 5-micron thick sections of the tumor tissue.

Note: The total amount of required tumor nuclei can be obtained by scraping up to 10 slides from the same block.

Additional Information: Unused unstained slides will not be returned.


Specimen Type: Cytology slides (direct smears or ThinPrep)

Slides: 1 to 3 Slides

Collection Instructions: Submit 1 to 3 slides stained and cover slipped with a preferred total of 5000 nucleated cells, or a minimum of at least 3000 nucleated cells.

Note: Glass coverslips are preferred; plastic coverslips are acceptable but will result in longer turnaround times.

Additional Information: Cytology slides will not be returned.

Useful For

Assisting in the clinical diagnosis of adult granulosa cell tumor by assessing gene targets with in the FOXL2 gene

Additional Tests

Test ID Reporting Name Available Separately Always Performed
SLIRV Slide Review in MG No Yes

Testing Algorithm

When this test is ordered, slide review will always be performed at an additional charge.

Method Name

Sequence Capture and Targeted Next-Generation Sequencing (NGS)

Reporting Name

FOXL2 Mutations Analysis, Tumor

Specimen Type


Specimen Minimum Volume

See Specimen Required

Specimen Stability Information

Specimen Type Temperature Time Special Container
Varies Ambient (preferred)

Clinical Information

Granulosa cell tumor (GCT) represents approximately 5% to 10% of all ovarian malignancies and is the most common type of malignant ovarian sex-cord stromal tumor. The majority of GCTs (95%) are adult type and 5% are juvenile type. Adult GCTs can occur at any age but most commonly occur in perimenopausal women, whereas juvenile GCTs arise in the first three decades of life. FOXL2 (forkhead box L2) gene is involved in ovarian development and function. The FOXL2 gene point mutation c.402C>G in exon 1 (p.C134W) has been reported in the majority of adult GCT (>90%), one molecular subtype of Sertoli-Leydig cell tumor, and rarely also in thecomas. In cases with challenging histopathology, detection of a FOXL2 mutation can aid in the clinical diagnosis of adult GCT.


This test uses formalin-fixed paraffin-embedded tissue or cytology slides to assess for the common somatic hotspot mutations in the FOXL2 gene. The results of this test can be useful for supporting a diagnosis of adult GCT.

Reference Values

An interpretive report will be provided.


The interpretation of molecular biomarker analysis includes an overview of the results and the associated diagnostic, prognostic, and therapeutic implications.

Clinical Reference

1. Shah SP, Kobel M, Senz J, et al: Mutation of FOXL2 in granulosa-cell tumors of the ovary. N Engl J Med. 2009 Jun;360(26):2719-2729

2. Kim MS, Hur SY, Yoo NJ, et al: Mutational analysis of FOXL2 codon 134 in granulosa cell tumour of ovary and other human cancers. J Pathol. 2010 Jun;221(2):147-152

3. Schrader KA, Gorbatcheva B, Senz J, 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

4. Benayoun BA, Kalfa N, Sultan C, Veitia, RA: The forkhead factor FOXL2: a novel tumor suppressor? Biochim Biophys Acta. 2010 Jan;1805(1):1-5

5. WHO Classification of Tumours Editorial Board: WHO Classification of Tumours. Vol 4. Female genital tumours. 5th ed. World Health Organization; 2021

Day(s) Performed

Monday through Friday

Report Available

12 to 20 days

Test Classification

This test was developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.

CPT Code Information

88381 - Microdissection, manual


LOINC Code Information

Test ID Test Order Name Order LOINC Value
XL2T FOXL2 Mutations Analysis, Tumor 95785-2


Result ID Test Result Name Result LOINC Value
617937 Result 82939-0
617938 Interpretation 69047-9
617939 Additional Info 48767-8
617940 Specimen 31208-2
617941 Tissue ID 80398-1
617942 Method 85069-3
617943 Disclaimer 62364-5
617944 Released By 18771-6