Presentation: Patient with lesions suggesting subcutaneous panniculitis-like T-cell lymphoma
Subcutaneous panniculitis-like T-cell lymphoma is a rare form of T-cell lymphoma. It presents with inflamed subcutaneous nodules, mimicking panniculitis. Patients with underlying constitutional (germline) pathogenic variants in HAVCR2 have increased risk of haemophagocytic lymphohistiocytosis, which can be life threatening.
Example clinical scenario
A patient with difficult-to-diagnose panniculitis presents for the results of a skin biopsy, which was in keeping with a subcutaneous panniculitis-like T-cell lymphoma (SPTCL).
When to consider genomic testing
- Genomic testing should be considered if:
- there is a clinical suspicion of SPTCL (to aid diagnosis); or
- there is a new diagnosis of SPTCL (to guide therapeutic management).
- HAVCR2 constitutional (germline) variants are associated with the life-threatening complication of haemophagocytic lymphohistiocytosis in a subset of SPTCL patients. It also indicates which patients may benefit from immunosuppressive therapy (such as cyclosporin) as opposed to chemotherapy. The identification of constitutional pathogenic variants in the HAVCR2 gene should also trigger cascade testing in the wider family.
- Referrals for testing will be triaged by the genomics laboratory. Testing should be targeted at cases in which a genetic or genomic diagnosis will guide management for the proband and/or family.
What do you need to do?
- Consult the National Genomic Test Directory. From here you can access the rare and inherited disease eligibility criteria, which provides information about individual tests and their associated eligibility criteria. You can also access a spreadsheet containing details of all available tests.
- For information about how to arrange testing in Wales, Scotland or Northern Ireland, see our dedicated Knowledge Hub resource.
- To find out which genes are included on different gene panels, see the NHS Genomic Medicine Service (GMS) Signed Off Panels Resource.
- The test to request in this case is R424.1 Subcutaneous panniculitis T-cell lymphoma (SPTCL). It comprises single gene sequencing for HAVCR2.
- This test does not include whole genome sequencing, so you should use your local Genomic Laboratory Hub for test order and consent (record of discussion) forms.
- This test is DNA-based, and an EDTA sample (typically a purple-topped tube) is required. The sample is best stored at four degrees Celsius until it can be posted to the genomics laboratory.
- Information about patient eligibility and test indications was correct at the time of writing. When requesting a test, please refer to the National Genomic Test Directory to confirm the right test for your patient.
Resources
For clinicians
- NHS England: National Genomic Test Directory
For patients
- My Lymphoma Team: Subcutaneous panniculitis-like T-cell lymphoma