Johnson, Emma F.

Background: Following transition to digital pathology for primary diagnosis at our institution, dermatology residents have reduced exposure to light microscopy. This study compares resident competency with light microscopy versus digital pathology following practice changes. Methods: Twenty-one dermatology residents were administered a dermatopathology examination composed of 32 diagnoses evaluated using digital slides and 32 with light microscopy. Case difficulty was graded and balanced between modalities. Diagnostic accuracy was measured using the number of correct diagnoses for each modality. Participants were surveyed regarding their experience and preferences. Results: Diagnostic accuracy was higher with digital pathology than light microscopy (22/32 vs. 18/32, P < 0.001). Diagnostic accuracy with digital pathology increased with years of training, but accuracy with light microscopy did not. Residents with previous light microscopy experience achieved an average score of 19/32 on glass, as compared with 10/32 for those without experience (P = 0.039). Digital pathology was preferred over light microscopy (18/21, 85.7%). Conclusions: Trainees had better diagnostic proficiency with digital pathology and preferred this modality. Most practices at this time continue to use light microscopy. Therefore, we need to maintain proficiency in microscopy during training while concurrently preparing trainees for a digital future.

AbstractHistiocytoid Sweet syndrome (H‐SS) is a histopathological variant of Sweet syndrome (SS) defined by cutaneous infiltration of immature myeloid cells morphologically resembling histiocytes. The association of H‐SS with underlying malignancy, particularly myelodysplastic syndromes, is well‐established. Myelodysplasia cutis (MDS‐cutis) has been proposed to describe cases historically diagnosed as H‐SS but characterized by shared clonality of the myeloid infiltrate in skin and bone marrow. Therefore, identifying patients who might have MDS‐cutis is critical for the management of the associated hematologic malignancy. VEXAS syndrome, an adult‐onset autoinflammatory disease, should also be included in the histopathologic differential diagnosis of H‐SS, as it shares clinical and pathologic features with MDS‐cutis. Through the presentation of two cases, we aim to highlight the defining features and key clinical implications of MDS‐cutis and VEXAS syndrome.

AbstractBackgroundTechnology has revolutionized not only direct patient care but also diagnostic care processes. This study evaluates the transition from glass‐slide microscopy to digital pathology (DP) at a multisite academic institution, using mixed methods to understand user perceptions of digitization and key productivity metrics of practice change.MethodsParticipants included dermatopathologists, pathology reporting specialists, and clinicians. Electronic surveys and individual or group interviews included questions related to technology comfort, trust in DP, and rationale for DP adoption. Case volumes and turnaround times were abstracted from the electronic health record from Qtr 4 2020 to Qtr 1 2023 (inclusive). Data were analyzed descriptively, while interviews were analyzed using methods of content analysis.ResultsThirty‐four staff completed surveys and 22 participated in an interview. Case volumes and diagnostic turnaround time did not differ across the institution during or after implementation timelines (p = 0.084; p = 0.133, respectively). 82.5% (28/34) of staff agreed that DP improved the sign‐out experience, with accessibility, ergonomics, and annotation features described as key factors. Clinicians reported positive perspectives of DP impact on patient safety and interdisciplinary collaboration.ConclusionsOur study demonstrates that DP has a high acceptance rate, does not adversely impact productivity, and may improve patient safety and care collaboration.

AbstractBackgroundWhile the list of fusion‐driven soft tissue neoplasms is expanding rapidly, their importance among cutaneous and superficial mesenchymal and adnexal neoplasms remains poorly understood. This challenge is especially evident in cases with ambiguous histopathology that are difficult to classify based on morphology.AimsOur goal was to investigate the benefits of next‐generation sequencing in diagnosing complex cutaneous neoplasms.Materials & MethodsDepartmental archives were searched for fusion‐driven cutaneous neoplasms. Slides were retrieved and clinical information including follow‐up was obtained.ResultsFifteen cases occurred in eight female and seven male patients, with a median age of 26 years (range: 1–83) at diagnosis. Tumors involved the extremities (9), scalp (5), and head and neck (1). Predominant features included myoepithelial (5), nested spindled with clear cytoplasm (2), atypical adnexal/squamoid (2), small round blue cell (2), cellular spindled (3), and fibrohistiocytic morphology (1). Most frequently encountered fusions involved EWSR1 (6) fused to ERG (1), FLI1 (1), CREB1 (2), CREM (1), PBX3 (1), followed by PLAG1 (4) with LIFR (2), TRPS1 (1) and CHCHD7. Additional fusions encountered were YAP1::NUTM1, EML4::ALK, SS18::SSX1 (2), and a novel fusion: ACTB::ZMIZ2. Integration of histologic features and molecular findings led to final diagnoses of primary cutaneous Ewing sarcoma (2), soft tissue myoepithelioma (4), cutaneous syncytial myoepithelioma (1), cutaneous adnexal carcinoma (1), porocarcinoma (1), inflammatory myofibroblastic tumor (1), synovial sarcoma (2), clear cell sarcoma (2), and angiomatoid fibrous histiocytoma (1).Discussion and conclusionOur results show that fusion testing can be a helpful diagnostic tool, especially in cases with unusual or uncommon morphology in superficial sites. Furthermore, it can allow for the identification of potential therapeutic targets in some instances.

AbstractIdiopathic eruptive macular pigmentation (IEMP) is a rare, benign, self‐resolving melanosis consisting of hyperpigmented macules typically on the face, trunk, and extremities that can occur in children and adolescents and often presents a diagnostic conundrum. We report a case involving an 8‐year‐old female whose previous clinical presentation was concerning for an atypical presentation of cutaneous mastocytosis or neurofibromatosis. The clinical and histopathologic evaluation was consistent with the diagnosis of IEMP, and no active intervention was pursued. Our accompanying literature review serves to better characterize this condition, highlight key diagnostic features, and emphasize the tendency for spontaneous resolution to avoid unnecessary treatments with limited clinical efficacy.

Abstract Background Majocchi’s granuloma (MG) is an uncommon deep fungal folliculitis predominantly caused by dermatophytes. Available data regarding predisposing comorbidities/risk factors, clinical characteristics, offending microbiologic pathogens, diagnostics, pathologic findings, and treatment approaches has been inferred from historical cases. Given these limitations in the existing literature of MG, we sought to conduct a detailed review of our institutional experience with biopsy-confirmed cases of MG. Methods Following IRB approval, we retrospectively identified and analyzed a multicenter cohort of adult patients diagnosed with MG between September 1992 and September 2022 at Mayo Clinic campuses (Figure 1). Data extracted included demographics, comorbid conditions, presenting clinical characteristics, diagnostic, microbiologic, and biopsy characteristics, treatment details, and outcomes. Figure 1 Flow Diagram show exclusion of patients from the final cohort. Results A total of 147 patients with MG with the accompanying baseline characteristics met study criteria (Table 1). One-hundred and five patients were male with a median age of 55.6 years. Immunosuppressant and topical corticosteroid use were common prior to development of MG (Table 1). Dermatologic lesions and their sites of involvement did not differ based on the immune status of patients (Table 2). Trichophyton rubrum was the most common causative pathogen of MG, in addition to other dermatophytes and fungal organisms (Table 3a). Treatment duration for all prescribed agents was median 31.5 days. Oral terbinafine was the most frequently utilized agent and clinical resolution was achieved in 96.6% of cases (Table 3b). Baseline Characteristics of 147 Patients with Majocchi’s Granuloma Diagnostic, Microbiologic, and Biopsy Characteristics, Treatment Characteristics and Outcomes Conclusion While rare and clinically variable in presentation, the diagnosis of MG requires careful clinical examination and history-taking, histopathologic confirmation, and frequently fungal culture. Most cases of MG in our study responded well to a course of oral terbinafine at a median of 31.5 days of treatment. Disclosures All Authors: No reported disclosures