Hurley, M. Yadira

BackgroundAppropriate use criteria (AUC) provide physicians guidance in test selection, and can affect health care delivery, reimbursement policy and physician decision‐making.ObjectivesThe American Society of Dermatopathology, with input from the American Academy of Dermatology and the College of American Pathologists, sought to develop AUC in dermatopathology.MethodsThe RAND/UCLA appropriateness methodology, which combines evidence‐based medicine, clinical experience and expert judgment, was used to develop AUC in dermatopathology.ResultsWith the number of ratings predetermined at 3, AUC were developed for 211 clinical scenarios involving 12 ancillary studies. Consensus was reached for 188 (89%) clinical scenarios, with 93 (44%) considered “usually appropriate,” 52 (25%) “rarely appropriate” and 43 (20%) “uncertain appropriateness.”LimitationsThe methodology requires a focus on appropriateness without comparison between tests and irrespective of cost.ConclusionsThe ultimate decision of when to order specific test rests with the physician and is one where the expected benefit exceeds the negative consequences. This publication outlines the recommendations of appropriateness—AUC for 12 tests used in dermatopathology. Importantly, these recommendations may change considering new evidence. Results deemed “uncertain appropriateness” and where consensus was not reached may benefit from further research.

BackgroundAppropriate use criteria have been developed for many tests using expert judgment, evidence‐based practice and clinical experience. In this context, we report the opinions of practitioners about clonality assays in various clinical scenarios where cutaneous lymphoma is suspected.MethodsAn Appropriate Use Criteria Task Force sponsored by the American Society of Dermatopathology (ASDP) synthesized clinical scenarios for cutaneous lymphoproliferative disorders (LPDs). We conducted, summarized and presented a relevant literature search to an audience of 144 dermatopathologists with a variety of practice experiences at the 53rd Annual Meeting of the ASDP in Chicago, IL.ResultsTwenty‐seven clinical scenarios for LPDs (13 T‐cell and 14 B‐cell) were defined. Forty relevant studies for T‐cell receptor gene clonality assays and 20 relevant studies for IgH/IgK clonality assays were identified. Audience response data from participating dermatopathologists reflected a wide variety of approaches to the application of clonality assays in the evaluation of LPDs, based on practice setting, personal experience and test availability.ConclusionsOur clinical scenario analysis and literature review revealed well‐supported clinical scenarios and identified opportunities for additional research to further define the utility of clonality assays in some clinical scenarios.

PEComas represent a family of uncommon mesenchymal tumors composed of “perivascular epithelioid cells” with a distinct immunophenotype that typically shows both myogenic and melanocytic differentiation. The PEComa family includes angiomyolipoma (AML), clear cell “sugar” tumor of the lung and extra pulmonary sites, lymphangioleiomyomatosis and clear cell myomelanocytic tumor of the falciform ligament/ligamentum teres. Very rarely, PEComas may arise in the skin. Primary cutaneous PEComas typically display a dermal proliferation of epithelioid cells with pale, clear, or granular pink cytoplasm arranged in nests and trabecula with an intervening arborizing network of delicate capillaries. Primary cutaneous PEComas have a lower frequency of myogenic marker expression than their deep soft tissue and visceral counterparts. They also often express strong diffuse CD10, leading to potential confusion with metastatic renal cell carcinoma. Most cases behave indolently. We report 5 additional cases of this rare entity. All showed classic histologic features and expression of either HMB‐45 and/or Melan‐A/MART‐1. Four cases were tested for myogenic markers (2 were positive & 2 were negative). Three cases were tested for CD10 (all 3 were positive). All of our cases with clinical follow‐up behaved indolently. Table 1 provides a summary of findings for all 5 cases in our series.