Sex Chromosome Determination, FISH, Tissue

Casandra

Casandra Test Code MC18480Version 1 (DRAFT)

Performing Lab

Lab Mayo Clinic LabLab Test ID SCTFCPT Codes 88271, 88274, 88275

Sex Chromosome Determination, FISH, Tissue

Clinical Use

Use

This test is useful for identifying the sex chromosome complement in paraffin-embedded tissues, which can help determine the sex of cells in tissue samples. It is particularly helpful in post-transplant contexts to identify opposite sex-donor cells and to resolve cases of suspected sample mix-up. The test uses a commercially available enumeration strategy probe set for the X centromere (DXZ1) and Y centromere (DYZ3).

Special Instructions

This test does not include a pathology consultation. If required, a separate PATHC / Pathology Consultation must be ordered. This test is not suitable for differentiating tissue from the same gender, as in a same-sex transplant or potential mix-up between two male or two female patients. It is advised to send specimens via Express Mail or an equivalent service if not on a courier service.

Limitations

The test is developed with an analyte specific reagent and is not cleared or approved by the FDA. It is best used as an adjunct to clinical and pathologic information. Non-formalin fixatives may not be successful for FISH assays, although non-formalin-fixed samples will not be rejected. Decalcified paraffin-embedded tissues are generally unsuccessful for FISH analysis and may lead to test cancellation.

Test Details

New York Approved

Methodology

Chromosomal / Cytogenetics (FISH)

Biomarkers

Unknown CNV

Copy Number Region

FISH • Copy Number • Categorical (e.g., Positive / Negative / Indeterminate)

Unknown CNV

Copy Number Region

FISH • Copy Number • Categorical (e.g., Positive / Negative / Indeterminate)

LOINC Codes

Order Codes

87436-2

Result Codes

50397-9
69965-2
87436-2

Result Turnaround Time

7-10 days

Specimen

Tissue (FFPE)

Volume

Not provided

Minimum Volume

Not provided

Container

Tissue block or slides

Collection Instructions

Submit a formalin-fixed, paraffin-embedded (FFPE) tumor tissue block. Alternative fixation methods may be acceptable with specification. For slides, submit four consecutive, unstained, 5 micron-thick sections placed on positively charged slides, and one H and E-stained slide.