See an October 2022 update with some additional facts and comments.
One of the first gene expression tests to help decide ambiguous pathology was the Veracyte AFIRMA test, for thyroid FNA cases that were not clearly benign or malignant.
Here's a MolDx LCD for similar tests designed for the difficult melanoma biopsy. It's DL39345, released on June 23 for comment. Find it here. Comment open til August 6.
The LCD has a direct cross-reference to L37859, "MyPath Melanoma Assay." It has a new proposed billing article, DA59109. The billing article lists the DL39345 as pertaining to 0090U (melanoma, mRNA, 23 genes) and 0314U (melanoma, mRNA, 35 genes). 0090U is Myriad MyPath, now, Castle MyPath, and 0314U is DecisionDx DiffDx Melanoma, also Castle. 0314U is in the CMS crosswalk/gapfill new code process this summer. 0090U is an ADLT test priced at $1950 in 2019 and still $1950 on the 2022 CLFS fee schedule.
The older myPath LCD has a short rule list:
- The test is ordered by a board-certified dermatopathologist,
- The specimen is an equivocal primary cutaneous melanocytic neoplasm,
- The patient may be subject to additional intervention, such as re-excision or sentinal node biopsy.
- The test is ordered by a board-certified or board-eligible dermatopathologist
- The specimen is a primary (non-metastatic, non-re-excision specimen) cutaneous melanocytic neoplasm for which the diagnosis is equivocal/uncertain (i.e., clear distinction between benign or malignant cannot be achieved using clinical and/or histopathological features alone) despite the performance of standard-of-care test procedures and relevant ancillary tests (i.e., immunohistochemical stains)
- The specimen includes an area representative of the lesion or portion of the lesion that is suspicious for malignancy
- The patient may be subjected to additional intervention, such as re-excision and/or sentinel lymph node biopsy, as a result of the diagnostic uncertainty
- The patient has not been tested with the same or similar assay for the same clinical indication
- The test is validated for use in the intended-use population and is performed according to its stated intended-use
- The test demonstrates Analytical and Clinical Validity (AV and CV) and Clinical Utility (CU) and undergoes a technical assessment (TA) by MolDx®to demonstrate compliance of the service with this policy
- The treatment differed from the pre-test recommendation in 55 of 77 (71.4%) cases, 44 of which produced a benign myPath® test result.
- Re-excision was the pre-test treatment recommendation for 41 of these 44 cases, yet re-excision was ultimately performed in just 7, indicating that a benign myPath® test result enabled dermatologists to forego further intervention in 33 of the 41 cases, yielding an 80.5% reduction in re-excisions.