Digital dermatopathology implementation: Experience at a multisite academic institution.

BACKGROUND: Technology 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. METHODS: Participants 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. RESULTS: Thirty-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. CONCLUSIONS: Our study demonstrates that DP has a high acceptance rate, does not adversely impact productivity, and may improve patient safety and care collaboration.

Histopathologic features of necrobiosis lipoidica.

BACKGROUND: Necrobiosis lipoidica (NL) is an uncommon granulomatous dermatosis that can occur in patients with or without associated diabetes mellitus (DM). Prior studies have attempted to determine distinctive histopathologic features of NL in patients with and without DM. METHODS: A retrospective review of 97 patients with NL was performed to determine the similar and distinctive histopathologic features in patients with DM and without DM. RESULTS: Of the 97 patients, 32% (n = 31) had DM. Epidermal acanthosis was seen more commonly in diabetics than nondiabetics (32.3% vs. 12.1%; p = 0.017). Naked (sarcoidal/tuberculoid) granulomas were more frequently observed in nondiabetics than diabetics (22.7% vs. 3.2%; p = 0.016). Eosinophils were more common in nondiabetics than diabetics (38.5% vs. 9.7%; p = 0.004), while neutrophilic infiltration was more common in diabetics than nondiabetics (45.2% vs. 17.5%; p = 0.004). CONCLUSIONS: This study corroborates well-documented histopathologic features of NL and shows distinctive histopathologic features of NL among patients with DM-I, DM-II, and without DM. These results support the hypothesis that there are different underlying drivers of NL between diabetics and nondiabetics.

Rates of Upstaging, Between Diagnosis and Surgery, and Clinical Management of Metastatic Cutaneous Squamous Cell Carcinoma: A Case-Control Study.

BACKGROUND: Cutaneous squamous cell carcinomas (cSCC) have upstage rates of approximately 10.3% to 11.1%. Data are currently limited on the rate of upstaging for metastatic cSCC. OBJECTIVE: The aim of this study was to determine the rates of upstaging, between diagnosis and surgery, and differences in management for metastatic and non-metastatic high-risk cSCC. MATERIALS AND METHODS: This was a retrospective, case-control, single institution, multi-center study. Univariate analysis was used. RESULTS: Sixty-eight subjects (34 metastatic & 34 non-metastatic) with 69 tumors were included. The overall rate of upstaging was 46.4%. The most common reasons for upstage were undocumented tumor size and under-diagnosis of poor differentiation. There were no differences in rates of upstaging. Preoperative imaging was performed in 43.6% of wide local excisions (WLE) versus 3.3% of Mohs micrographic surgery (MMS; p < .001). The median days from surgery to sentinel lymph node biopsy (SLNB), or nodal dissection was shorter for WLE versus MMS (0 vs 221 days, p < .001). CONCLUSION: Improved clinical documentation, including documenting tumor size, and the identification of pathologic risk factors, including poor differentiation and depth of invasion, are needed for proper staging. Preoperative imaging and discussion of SLNB may be beneficial for high-risk T2b and T3 tumors.

Chronic graft-versus-host disease in pancreas after kidney transplant recipients - An unrecognized entity.

Graft-versus-host disease (GVHD), a common complication after peripheral blood stem cell or bone marrow transplantation, rarely occurs in kidney and pancreas transplant recipients. The true incidence may be confounded by the rarity of the disorder, with a resultant lack of appreciation of the diagnosis as a potential cause of common clinical manifestations such as cytopenias and immune dysfunction. Reports of GVHD in kidney and pancreas transplant recipients almost uniformly describe patients in the early posttransplant period (days to months) with the typical manifestations of acute GVHD involving the skin, liver, and intestines. In contrast, reports of solid organ transplant recipients with clinical features more consistent with chronic GVHD (cGVHD) are lacking, raising concern of underrecognition of this severe complication. Occurrence later after transplant may be even more likely to result in lack of recognition. We report 2 cases of possible cGVHD occurring in recipients of pancreas after kidney transplantation, which were diagnosed at 5.5 and 42 months after pancreas transplant. Both patients presented with severe pancytopenia, multiple opportunistic infections, and features suggestive of cGVHD. Transplant professionals should be aware of the possibility of acute and cGVHD in pancreas after kidney transplant recipients and be able to recognize the clinical manifestations.

Panniculitis in a patient with metastatic renal cell carcinoma on a tyrosine kinase inhibitor.

A 71-year-old female was diagnosed with localized renal cell carcinoma in July 2008 with subsequent metastasis in 2012 to the right adrenal gland, lungs, and brain. Due to disease progression, she was started on pazopanib 800 mg daily in October 2012. In November 2016, the patient developed an ill-defined, red, 10 × 15 cm indurated plaque on the left lateral upper thigh with a discrete 3 cm firm tender tumor without ulceration. An incisional biopsy was performed and showed panniculitis with features resembling sclerosing lipogranuloma. Alternative causes including rheumatologic disease and trauma were ruled out. We report the first case of pazopanib-induced panniculitis. Key clinical and histopathological features include tender subcutaneous nodules, exclusion of other causes, and fatty microcysts within a densely sclerotic background on pathology. As targeted therapies are becoming increasingly common in the field of oncology, prompt identification and reporting of adverse reactions is critical for proper management.

High GILT Expression and an Active and Intact MHC Class II Antigen Presentation Pathway Are Associated with Improved Survival in Melanoma.

The MHC class I Ag presentation pathway in melanoma cells has a well-established role in immune-mediated destruction of tumors. However, the clinical significance of the MHC class II Ag presentation pathway in melanoma cells is less clear. In Ag-presenting cells, IFN-γ-inducible lysosomal thiol reductase (GILT) is critical for MHC class II-restricted presentation of multiple melanoma Ags. Although not expressed in benign melanocytes of nevi, GILT and MHC class II expression is induced in malignant melanocytes in a portion of melanoma specimens. Analysis of The Cancer Genome Atlas cutaneous melanoma data set showed that high GILT mRNA expression was associated with improved overall survival. Expression of IFN-γ, TNF-α, and IL-1ß was positively associated with GILT expression in melanoma specimens. These cytokines were capable of inducing GILT expression in human melanoma cells in vitro. GILT protein expression in melanocytes was induced in halo nevi, which are nevi undergoing immune-mediated regression, and is consistent with the association of GILT expression with improved survival in melanoma. To explore potential mechanisms of GILT's association with patient outcome, we investigated pathways related to GILT function and expression. In contrast to healthy skin specimens, in which the MHC class II pathway was nearly uniformly expressed and intact, there was substantial variation in the MHC class II pathway in the The Cancer Genome Atlas melanoma specimens. Both an active and intact MHC class II pathway were associated with improved overall survival in melanoma. These studies support a role for GILT and the MHC class II Ag presentation pathway in melanoma outcome.

How to Sequence Therapies in Mycosis Fungoides.

OPINION STATEMENT: Choice of therapy in mycosis fungoides is based on both patient- and lymphoma-specific factors, such as disease characteristics, comorbidities, symptoms and effect on quality of life, potential associated toxicities of therapy, response and tolerance to prior lines of therapy, and convenience and practicality. Generally, we sequence therapies from least toxic, targeted, nonimmunosuppressive to more toxic, immunosuppressive and from single agent to multiple agents, as necessary. If more toxic, immunosuppressive agents are required to alleviate disease burden or symptoms, we generally use them just long enough to control the disease, then transition to a maintenance regimen with less toxic, less immunosuppressive agents.

A rare case of childhood mucous membrane pemphigoid involving the oral and genital mucosa.

Mucous membrane pemphigoid (MMP) is a rare chronic immunobullous disease that involves the mucous membranes and may result in significant scarring and complications if diagnosis is delayed. MMP typically occurs in elderly patients, with very few cases reported in children. Here, we present a 12-year-old female patient with childhood-onset oral and genital MMP, clinically suspected to be lichen sclerosus, but eventually diagnosed as MMP after multiple supportive biopsies and confirmatory direct immunofluorescence. Although treatment was challenging, the combined use of systemic corticosteroids, dapsone, and mycophenolate mofetil was ultimately successful in achieving disease control.

Cutaneous B cell pseudolymphoma treated with rituximab and methotrexate.

Cutaneous B cell pseudolymphoma (CBPL), or cutaneous lymphoid hyperplasia, is the most common pseudolymphoma. It typically responds well to local treatment and follows a benign course. Herein, we describe the unique case of a patient with CBPL that was refractory to a variety of treatments, with subsequent response to rituximab followed by methotrexate. This case explores the complex interplay of T and B lymphocytes, and the potential role of perifollicular T cells in treatment resistant CBPL. Further, it describes the additive therapeutic effect of rituximab and methotrexate to target both B cell and T cell populations in CBPL, a strategy already employed in a number of other conditions.

Prognostic value of inositol polyphosphate-5-phosphatase expression in recurrent and metastatic cutaneous squamous cell carcinoma.

BACKGROUND: Inositol polyphosphate-5-phosphatase (INPP5A) has been shown to play a role in the progression of actinic keratosis to cutaneous squamous cell carcinoma (cSCC) and the progression of localized disease to metastatic disease. Currently, no cSCC biomarkers are able to risk stratify recurrent and metastatic disease. OBJECTIVE: To determine the prognostic value of INPP5A expression in cSCC recurrent and metastatic disease. METHODS: We conducted a multicenter, single-institutional, retrospective cohort study within the Mayo Clinic Health System on the use of immunohistochemical staining to examine cSCC INPP5A protein expression in primary tumors and recurrent and metastatic disease. Dermatologists and dermatopathologists were blinded to outcome. RESULTS: Low staining expression of INPP5A in recurrent and metastatic disease tumors was associated with poor overall survival (OS) (31.0 months for low versus 62.0 months for high expression; P = .0272). A composite risk score (calculated as score of primary tumor + score of recurrent or metastatic disease tumor, with tumors with high expression scoring a zero and low expression a 1, score range 0-2) of 0 was predictive of improved OS compared with a composite risk score of ≥1 (hazard ratio 0.42, 95% confidence interval 0.21-0.84; P = .0113). LIMITATIONS: This is a multicenter but single institution study of a white population. CONCLUSION: Loss of INPP5A expression predicts poor OS in recurrent and metastatic disease of cSCC.

A case of pediatric lymphomatoid papulosis treated with photodynamic therapy and narrowband ultraviolet B.

We report a case of a 13-year-old boy with extensive lymphomatoid papulosis (LyP) involving his elbows, forearms, proximal thighs, and right hip, with treatment-resistant nodules on his right forearm. He was treated with full-body narrowband ultraviolet B and targeted photodynamic therapy (PDT) with 20% aminolevulinic acid (ALA). After two months, there was complete resolution of the right forearm nodules. Due to its minimal toxicity, PDT offers unique advantages and may be considered for pediatric LyP patients with symptomatic, localized disease resistant to conventional treatments.

The prognostic value of inositol polyphosphate 5-phosphatase in cutaneous squamous cell carcinoma.

BACKGROUND: Inositol polyphosphate 5-phosphatase (INPP5A) has been shown to play a role in development and progression of cutaneous squamous cell carcinoma (cSCC). The goal of the current study was to explore the prognostic value of INPP5A expression in cSCC. METHODS: A total of 189 cases of actinic keratosis and SCC in 174 patients were identified; clinical and outcome data were abstracted, histopathology was rereviewed, and immunohistochemical staining and interpretation was performed for INPP5A. RESULTS: The majority of tumors (89.4%) had an INPP5A score of 2 or 3. No patients had complete loss of INPP5A. Tumors with an INPP5A score of 1 were more likely to be intermediate- to high-risk tumors (Brigham and Women's Hospital stage ≥T2a 85.0% vs 23.7% [P < .0001]) characterized by a larger diameter (2.4 cm vs 1.3 cm [P = .0004]), moderate-to-poor differentiation (86.7% vs 17.6% [P < .0001]), and perineural invasion (37.5% vs 5.3%, [P < .0001]). An INPP5A score of 1 was associated with a worse 3-year survival (a rate of 42.3% [hazard ratio, 2.81, P = .0006]) and a local metastasis rate of 48.0% (hazard ratio, 4.71; P < .0001). CONCLUSIONS: Low INPP5A scores are predictive of aggressive tumors and may be a useful adjunct to guide clinical management of cSCC.

Congenital eccrine angiomatous hamartoma: Expanding the morphologic presentation and a review of the literature.

Eccrine angiomatous hamartoma (EAH) is a rare benign vascular hamartoma characterized histologically by an increased size and number of mature eccrine glands associated with multiple foci of dilated capillaries in the dermis and subcutis. EAH typically presents in children as discrete, solitary nodules, or plaques most commonly located on the extremities. Some cases of EAH have an agminated distribution involving classic locations, or present as solitary lesions in less common locations such as the face, scalp, or trunk. We report the case of congenital EAH in a child with atypical morphological features and pattern of distribution further expanding on the range of presentations classically described.

Necrobiotic xanthogranuloma: a 30-year single-center experience.

To characterize the clinical features, associated disorders, and treatment of necrobiotic xanthogranuloma (NXG), a rare non-Langerhans cell histiocytosis, we conducted a retrospective review of pathologically confirmed NXG at Mayo Clinic Arizona from 1987 to June 2017. Data on clinical findings, laboratory findings, associated disorders, therapy, and response to therapy were extracted. Nineteen patients were identified. Mean age was 54 years (range, 17-84) with equal gender distribution. Median follow-up was 5.5 years (range, 1-18). Most patients had a detectable monoclonal protein (84%), and IgG kappa constituted 58%. The most common cutaneous lesions involved the periorbital region (53%). The majority of patients had extracutaneous manifestations, most commonly affecting the liver (32%) and the sinuses (21%). Hematologic malignancies were diagnosed in 26% of patients and included Hodgkin lymphoma, chronic lymphocytic leukemia (CLL), smoldering myeloma, and multiple myeloma. The most common treatment was chlorambucil with or without systemic corticosteroids. Response was seen in most patients (95%), and most patients received 1-3 lines of therapy (74%). NXG is a reactive histiocytic disorder that commonly involves multiple organ systems and requires a high degree of clinical suspicion for accurate diagnosis. Treatment decisions should be based on coexisting conditions and pattern of disease involvement.

Clinical and histopathologic features of paraneoplastic granuloma annulare in association with solid organ malignancies: A case-control study.

BACKGROUND: Granuloma annulare (GA) is a granulomatous skin eruption rarely associated with cancer. We report seven cases of paraneoplastic GA in association with solid organ malignancy. OBJECTIVE: To compare the clinical and histopathological features of paraneoplastic GA to case-matched controls of classic GA. METHODS: Retrospective chart and histopathological review of 7 individuals and 13 age- and sex-matched controls. Paraneoplastic GA was defined as GA occurring within 6 months of the diagnosis of solid organ malignancy and/or persistent GA that resolved with cancer treatment. RESULTS: Most cases of paraneoplastic GA were associated with lung cancer (4/7). The clinical and histopathological features of paraneoplastic and classic GA were similar. Compared to classic GA, paraneoplastic GA cases were more often generalized disease (6/7 vs 6/13), refractory to treatment, and had a perivascular inflammatory cell infiltrate (5/7 vs 2/13). All cases of paraneoplastic GA that underwent definitive treatment of their cancer improved. LIMITATIONS: Single-institution, retrospective review with a small sample size. CONCLUSION: Paraneoplastic GA is rare, similar to classic GA, and refractory to treatment. We advocate for age-appropriate screening in individuals with GA that is nonresponsive to multiple lines of systemic treatment and evaluating patients with concerning signs or symptoms for an underlying neoplasm.

Melanoma mimicking Rosai-Dorfman disease.

Despite well-defined clinical and histopathological features of melanoma, atypical presentations mimicking other skin disorders can result in a delayed diagnosis or misdiagnosis and subsequent inappropriate treatment. Rosai-Dorfman disease (RDD) is a rare histiocytic disorder with unique clinical and histopathological features. We report a case of melanoma treated with cryotherapy that mimicked RDD both clinically and histopathologically. We compare this RDD-like melanoma to classic RDD, outlining the importance of clinicopathological correlation prior to treatment, as well as the potential pitfalls in diagnosis after cryotherapy of pigmented lesions.

Prurigo pigmentosa after a strict ketogenic diet.

Prurigo pigmentosa (PP) is a rare inflammatory dermatosis of unknown cause characterized by a predominantly truncal eruption of pruritic erythematous papules in a reticular pattern, resolving with hyperpigmentation. PP is twice as common in girls and women, and the mean age at onset is 25 years. Diagnosis of PP is challenging and is aided by characteristic histopathologic findings. We report a case of PP in a 17-year-old white boy. The eruption arose during strict adherence to a ketogenic diet.

Superficial CD34-positive fibroblastic tumor: report of 18 cases of a distinctive low-grade mesenchymal neoplasm of intermediate (borderline) malignancy.

Fibroblastic mesenchymal tumors show a spectrum of biological behavior, from benign to fully malignant. We report our experience of two decades with a distinctive, previously undescribed low-grade fibroblastic tumor of the superficial soft tissues. Eighteen cases were identified within our consultation files, previously coded as 'low-grade sarcoma, not further classified' and 'malignant fibrous histiocytoma, low grade'. The tumors occurred in adults (median age 38 years, range 20-76 years) of either sex (10 males and 8 females), ranged in size from 1.5 to 10 cm (mean 4.1 cm), and were confined to the superficial soft tissues of the thigh (N=5), knee (N=2), and other sites. Histological features included a fascicular growth pattern of the neoplastic spindled cells with striking, often bizarre cellular pleomorphism and variably prominent nucleoli. Necrosis was seen in one case. All cases showed strong, diffuse CD34 positivity and 68% of tested cases demonstrated focal cytokeratin expression. Desmin, ERG, FLI-1, smooth muscle actin, and S100 protein were negative. TP53 overexpression was absent. Fluorescence in-situ hybridization studies for TGFBR3 and/or MGEA5 rearrangements were negative in all tested cases. Clinical follow-up was available in 13 patients (median duration of 24 months; range 1-104 months). Twelve of 13 patients had no disease recurrence. One patient had regional lymph node metastases, 7 years after incomplete excision of the primary tumor. All patients are currently alive and disease free. The unique clinicopathological features of superficial CD34-positive fibroblastic tumor define them as a novel subset of low-grade fibroblastic neoplasms, best considered to be of borderline malignancy.