American Society of Dermatopathology

View all recommendations from this society

October 17, 2018

Do not routinely perform T-cell receptor (beta and gamma) gene rearrangements on inflammatory / reactive lesions or papular / papulonecrotic eruptions when there is clinical and histologic concordance for a diagnosis of pityriasis lichenoides or lymphomatoid papulosis.

Although clonality assays such as T-cell receptor beta and gamma studies can be useful in the detection of monoclonality in lymphoproliferative disorders, there are limitations in the sensitivity and specificity of the test. In addition, the test has a high false positive rate making it unreliable in differentiating between benign inflammatory dermatoses and T-cell lymphoproliferative disorders.

These items are provided solely for informational purposes and are not intended as a substitute for consultation with a medical professional. Patients with any specific questions about the items on this list or their individual situation should consult their physician.

How The List Was Created

The American Society of Dermatopathology (ASDP) is committed to improving the quality of lives by continually advancing the theory and practice of dermatopathology. In 2015, under the vision of the then Society President, Dr. Dirk Elston, the Appropriate Use Criteria (AUC) Task Force was created to help guide dermatopathologists and inform their clinical colleagues in their use of ancillary studies performed in dermatopathology in specific clinical scenarios. The overarching goal of producing AUC is high quality care, lowering costs, and ensuring efficient use of laboratory resources. The Task Force, which is now a committee, identified ancillary studies performed in dermatopathology encompassing four broad areas. These include: lymphoproliferative, melanocytic, soft tissue, and other, which includes entities that do not fit into one of the aforementioned groups. Using the methodology developed by RAND/ UCLA, which combines best scientific evidence with expert opinion, patient-centered guidelines (appropriateness ratings) have been created for ancillary studies used in dermatopathology. The AUC are used to develop these recommendations. The recommendations list was reviewed and approved by the ASDP Ethics Committee and Board of Directors.


Comfere N, Sundram U, Yadira Hurley M, Swick B. Views of Dermatopathologists about Clonality Assays in the Diagnosis of Cutaneous T cell and B cell Lymphoproliferative Disorders. J Cutan Pathol. 2018 Jan;45(1):39-47.

Vidal CI, Armbrect EA, Andea AA, et al. Appropriate Use Criteria in Dermatopathology: Initial Recommendations from the American Society of Dermatopathology. J Cutan Pathol. 2018 Aug;45(8):563-580 (full version) and J Am Acad Dermatol. 2018 Apr 21. [Epub ahead of print] (abbreviated version) [co-published].

Zhang B, Beck AH, Taube JM, et al. Combined use of PCR-based TCRG and TCRB clonality tests on paraffin embedded skin tissue in the differential diagnosis of mycosis fungoides and inflammatory dermatoses. J Mol Diagn 2010 May; 12(3): 320-7.