Acral melanocytic neoplasms often pose diagnostic difficulty. Preferentially expressed antigen in melanoma (PRAME) expression and loss of p16 expression have diagnostic utility in melanocytic tumors. ...We examined PRAME and p16 expression in 30 acral melanocytic neoplasms (n = 11 nevi; n = 2 dysplastic nevi; n = 7 Spitz nevi; n = 10 acral melanomas). PRAME was scored as % positive nuclei: negative = 0%; 1% to 25% = 1+; 25% to 50% = 2+; 50% to 75% = 3+, or positive: 75% to 100% = 4+. p16 expression was defined as retained (homogeneous or checkerboard) or lost (complete or partial/regionally). PRAME expression was negative in all benign, dysplastic, and Spitz nevi. Conversely, all acral melanomas were diffusely (4+) positive for PRAME expression. p16 expression was retained in all benign acral nevi (8/11 homogeneous, 3/11 checkerboard), completely lost in one dysplastic nevus, and retained in all acral Spitz nevi (3/7 homogeneous, 4/7 checkerboard). p16 was retained in five of 10 acral melanomas (3/10 homogeneous; 2/10 checkerboard), and negative in five of 10 acral melanomas (absent in 3/10, partially lost in 2/10). Our data suggest that 4+ PRAME expression is highly sensitive and specific in the setting of acral melanomas and is a more predictive diagnostic tool compared with p16 immunohistochemistry.
The current classification for alopecia areata (AA) does not provide a consistent assessment of disease severity.
To develop an AA severity scale based on expert experience.
A modified Delphi process ...was utilized. An advisory group of 22 AA clinical experts from the United States was formed to develop this AA scale. Representatives from the pharmaceutical industry provided feedback during its development.
Survey responses were used to draft severity criteria, aspiring to develop a simple scale that may be easily applied in clinical practice. A consensus vote was held to determine the final AA severity statement, with all AA experts agreeing to adopt the proposed scale.
The scale is a static assessment intended to be used in clinical practice and not clinical trials.
The final AA disease severity scale, anchored in the extent of hair loss, captures key features commonly used by AA experts in clinical practice. This scale will better aid clinicians in appropriately assessing severity in patients with this common disease.
Background
Dermatologists play an important role in diagnosing and managing hospitalized patients with cutaneous abnormalities. Skin biopsies remain an indispensable tool for aiding dermatologists in ...accurate diagnosis and treatment. We aimed to determine the range of conditions, and the most common conditions, prompting skin biopsy by dermatology hospital consultation (HCON) services to aid in evaluation of hospitalized patients.
Methods
All hospitalized patients seen by a single tertiary care center dermatology HCON service between 2015 and 2018 who had associated skin biopsies were identified. Histologic features and clinical diagnoses of each patient were classified into 13 histologic reaction pattern categories.
Results
Eight hundred and thirty one inpatients evaluated by our dermatology HCON service had 914 skin biopsies. The most frequent diagnostic categories prompting biopsy were vasculopathic (17.6%), interface dermatitis (16.5%), infectious (12.6%), and spongiotic dermatitis (10.9%). The most frequent diagnostic categories included drug reaction (13.2%), leukocytoclastic vasculitis (8.5%), skin cancer (5.4%), graft‐vs‐host disease (3.5%), connective tissue disease (3.3%), and calciphylaxis (3.0%).
Conclusion
Our study suggests a variety of serious diseases affecting inpatients prompts biopsy by dermatology consultation services. Educational curricula for dermatology and pathology residents, fellows, and staff designed with these data may enhance knowledge that improves the quality of inpatient dermatology care.
Sentinel lymph node biopsy is used to stage Merkel cell carcinoma, but its prognostic value has been questioned. Furthermore, predictors of outcome in sentinel lymph node positive Merkel cell ...carcinoma patients are poorly defined. In breast carcinoma, isolated immunohistochemically positive tumor cells have no impact, but in melanoma they are considered significant. The significance of sentinel lymph node metastasis tumor burden (including isolated tumor cells) and pattern of involvement in Merkel cell carcinoma are unknown. In this study, 64 Merkel cell carcinomas involving sentinel lymph nodes and corresponding immunohistochemical stains were reviewed and clinicopathologic predictors of outcome were sought. Five metastatic patterns were identified: 1, sheet-like (n=38, 59%); 2, non-solid parafollicular (n=4, 6%); 3, sinusoidal, (n=11, 17%); 4, perivascular hilar (n=1, 2%) and 5, rare scattered parenchymal cells (n=10, 16%). At the time of follow-up, 30/63 (48%) patients had died with 21(33%) attributable to Merkel cell carcinoma. Patients with pattern 1 metastases had poorer overall survival compared with patients with patterns 2–5 metastases (p=0.03), with 22/30 (73%) deaths occurring in pattern 1 patients. 3 (10%) deaths occurred in patients showing pattern 5, all of whom were immunosuppressed. 4 (13%) deaths occurred in pattern 3 patients and 1 (3%) death occurred in a pattern 2 patient. In multivariable analysis, the number of positive sentinel lymph node (1 or 2 versus >2, p<.0001), age (<70 versus ≥70, p=.01), sentinel lymph node metastasis pattern (patterns 2–5 versus 1, p=.02), and immune status (immunocompetent versus suppressed, p=.03) were independent predictors of outcome, and could be used to stratify Stage III patients into 3 groups with markedly different outcomes. In Merkel cell carcinoma, the pattern of sentinel lymph node involvement provides important prognostic information and utilizing this data with other clinicopathologic features facilitates risk stratification of Merkel cell carcinoma patients that may have management implications.
Dermatitis artefacta is a psycho-cutaneous disorder characterized by self-inflicted cutaneous injuries, often in association with an underlying psychiatric disorder or as a response to external ...stressors. Cutaneous lesions suggestive of dermatitis artefacta are dependent on the means of injury and thus may be morphologically variable, but typically have geometric shapes, spare hard-to-reach anatomic areas, and are present in variable stages of evolution at any specific time. Although a dermatologist may be suspicious of dermatitis artefacta in a given patient, making a definitive diagnosis is extremely challenging. Patients often clinically evade questioning and deny creating skin lesions, and histopathologic evaluation of lesional biopsies usually reveals non-specific epidermal and dermal changes and inflammation. Thus, identification of clues that lend support to a diagnosis of dermatitis artefacta would be welcomed by both clinicians and pathologists. Here we present a case of dermatitis artefacta with a unique, yet previously reported, histopathological finding of multinucleated keratinocytes within the epidermis. Although probably uncommon and dependent on the etiology of cutaneous injury, we believe this finding is important for dermatopathologists to be aware of as a potential diagnostic clue when evaluating biopsies in patients suspected to have dermatitis artefacta.