Ackerman Academy of Dermatopathology

Melanoma may mimic a variety of skin lesions clinically and histopathologically, and presents diagnostic challenges. In this article, we describe a case of melanoma in an 89-year-old man with a very rare histopathologic presentation, namely the presence of pleomorphic and multinucleated giant cells with abundant cytoplasm, highly resembling an atypical fibroxanthoma. The differential diagnoses in conjunction with the findings in immunohistochemical study are also discussed.

Acquired perforating dermatoses (APDs) are a group of diverse skin disorders in patients with systemic disease, most commonly chronic renal failure and diabetes mellitus. APD induced by medication has seldom been reported. Anti-PD-1 monoclonal antibody has recently been used as a broad-spectrum, effective, durable, and relatively safe antitumor therapy for various malignancies. Thus far, known side effects involving skin have included rash, pruritus, and vitiligo. Here, we present a rare case of a unilateral linear eruption with histopathologic features of APD in a 36-year-old man during treatment with Terepril monoclonal antibody. To the best of our knowledge, APD induced by the PD-1 inhibitor has not been described in the medical literature.

The histology of erythema (chronicum) migrans (ECM) is classically described as a nonspecific perivascular infiltrate with a variable number of plasma cells and eosinophils. However, deviations from this pattern were described, such as focal interface changes or spongiosis, potentially posing a clinicopathological challenge. In this study, cases submitted with a serologically confirmed, clinically unequivocal, or highly suspicious diagnosis of ECM/Lyme disease between January 01, 2016, and September 01, 2018, were retrieved from the electronic database system and reviewed to delineate the histopathologic features of ECM. The series consisted of 14 cases. A superficial perivascular lymphocytic infiltrate was noted in all biopsies, accompanied by a deep and/or interstitial inflammatory infiltrate in 9 cases (64%). The inflammation ranged from relatively sparse to dense and prominent. At least focal interface changes were noted in 12 biopsies (86%). Eosinophils and plasma cells were noted in 7 (50%) and 10 (71%) cases, respectively. From a histologic standpoint, ECM is a protean entity and may manifest with a variable density of perivascular and/or interstitial lymphocytic infiltrate admixed with eosinophils and/or plasma cells and accompanied by focal interface dermatitis. Within the appropriate clinical context, ECM should be considered in the differential diagnosis of focal interface and/or sparse perivascular dermatitis.

Ackerman Academy of Dermatopathology, New York, NY. Correspondence: Ali Rashidbaigi, MD (e-mail: [email protected]). The authors declare no conflicts of interest.

Hailey-Hailey disease (familial benign chronic pemphigus) is a genodermatosis with a typical clinical presentation of macerated plaques involving intertriginous areas of the body and affects multiple family members. Epidermal acanthosis, incipient, and completed acantholysis of many of the spinous keratinocytes of the epidermis and foci of dyskeratosis are well-recognized histologic findings. We have observed solitary lesions on the "scalp" of patients having a Hailey-Hailey-like pattern, and not the suprabasilar clefting of pemphigus represents the first manifestation of pemphigus vulgaris, which was confirmed with direct immunofluorescence in all our patients.

Kazlouskaya, Viktoryia MD, PhD; Ugorji, Rex MD; Heilman, Edward MD; Gottesman, Silvija P. MD Author Information

Ackerman Academy of Dermatopathology, New York, NY. Correspondence: Ali Rashidbaigi, MD (e-mail: [email protected]). The authors declare no conflicts of interest.

Angiolymphoid hyperplasia with eosinophilia (ALHE) is an uncommon, idiopathic vascular disorder. It manifests as dermal or subcutaneous red to brown papules or nodules, most commonly on the head and neck; other less common sites include the trunk, extremities, genitalia, lips, and oral mucosa. Although ALHE is a benign disease, lesions are often persistent and difficult to eradicate. ALHE occurs more frequently in Asian young and middle-aged women. Histologically, it is characterized by a florid vascular proliferation with hobnail epithelioid endothelial cells surrounding by lymphocytic and eosinophilic infiltrate. Here, we reported congenital ALHE in a 2-year-old girl. Unilateral lesions had a blaschkoid segmental distribution in the anogenital region and were successfully treated with the Nd:YAG laser.