Galina Y. Stetsenko

CD4+/CD56+ hematodermic neoplasm: report of a rare variant with a T-cell receptor gene rearrangement.

CD4+/CD56+ hematodermic neoplasm (HN), formerly known as a blastic natural killer (NK) cell lymphoma, is a rare subtype of a cutaneous dendritic cell neoplasm notable for highly aggressive behavior. The characteristic features are: expression of the T‐helper/inducer cell marker CD4 and the NK‐cell marker CD56 in the absence of other T cell or NK‐cell specific markers. In particular, CD3 (surface or cytoplasmic) and CD2 are not expressed. Although T‐cell receptor (TCR) genes are generally reported to be in a germline configuration, we present an unusual variant of a CD4+/CD56+ HN with a clonal rearrangement of TCR genes. This feature of a CD4+/CD56+ HN has been only rarely reported. Recognition of the presence of clonal TCR gene rearrangements in a small subset of CD4+/CD56+ HN is important to avoid misdiagnosis of this entity as an unusual variant of a cutaneous T‐cell lymphoma.

p63 Expression in Merkel Cell Carcinoma Predicts Poorer Survival yet May Have Limited Clinical Utility

OBJECTIVES To determine the clinical utility of p63 expression, which has been identified in several cohorts as a predictor of poorer prognosis in Merkel cell carcinoma (MCC). METHODS Immunohistochemistry was used to determine p63 expression on MCC tumors from 128 patients. RESULTS Of the patients, 33% had detectable p63 expression. p63 Positivity was associated with an increased risk of death from MCC (hazard ratio, 2.05; P = .02) in a multivariate Cox regression model considering stage at presentation, age at diagnosis, and sex. Although p63 expression correlated with diminished survival in this largest cohort reported thus far, the effect was weaker than that observed in prior studies. Indeed, within a given stage, p63 status did not predict survival in a clinically or statistically significant manner. CONCLUSIONS It remains unclear whether this test should be integrated into routine MCC patient management.

Unusual granulomatous variant of scleromyxedema

Scleromyxedema is notable for significant morbidity and mortality. A generalized eruption of waxy papules in the absence of thyroid disease with histologic findings of mucin deposition, increased fibroblast proliferation, and fibrosis are the characteristic features of scleromyxedema. We report a case of scleromyxedema that, on histology, was associated with interstitial granuloma annulare-like features. Based on our literature review, this is a rare presentation of this disease. Familiarity with the histologic aspects of scleromyxedema, as described in this report, can help to improve the accuracy of this diagnosis, particularly in atypical presentations.

Subungual Bowen disease in a patient with epidermodysplasia verruciformis presenting clinically as longitudinal melanonychia.

Epidermodysplasia verruciformis (EV) is a rare autosomal-recessive condition associated with a predisposition to infection with specific types of human papillomaviruses. A spectrum of wart-like lesions on the face, dorsa of the hands, and legs are characteristic clinical findings. Lesions usually develop in early childhood, persist, and may eventuate in cutaneous squamous cell carcinoma, usually in sun-exposed areas. These lesions are locally destructive and sometimes metastasize. We present a case of a 34-year-old African American woman with EV with a 9-month history of a right index finger ungual longitudinal pigmented band and nail splitting. Biopsy showed hyperkeratotic and parakeratotic subungual epithelium with verrucous hyperplasia. The superficial keratinocytes showed koilocytic changes. In addition, there was extensive, focally full-thickness keratinocyte dysmaturation with variable nuclear atypia and numerous mitotic figures, without apparent invasion. An associated melanocytic hyperplasia (confirmed by Melan-A stain), composed of large, pigment-laden dendritic melanocytes, was present without appreciable atypia or pagetoid spread. The findings are of a squamous cell carcinoma in situ arising in association with EV with incidental melanocytic hyperplasia. To the best of our knowledge, this is first report of a subungual presentation of this condition with associated melanonychia.

Granulomatous scleromyxedema: case report and literature review.

Scleromyxedema is a rare and frequently disabling disease characterized by generalized waxy papules, skin induration, and cardinal histological features of dermal fibroblastic proliferation, thickened collagen, and mucin deposition. A monoclonal gammopathy is almost always present with rare progression to multiple myeloma. We describe the case of a 54-year-old man who presented with a rash in the setting of a new medication and histological features suggesting a granulomatous drug reaction. Despite discontinuation of the medication, the rash persisted and a second biopsy confirmed an interstitial granulomatous pattern. Serum protein electrophoresis identified the presence of a biclonal gammopathy leading to a diagnosis of granulomatous scleromyxedema. Review of the medical literature reveals only a handful of well-documented similar cases of this rare variant. It is important for pathologists and clinicians to be familiar with this condition to facilitate timely diagnosis and optimal clinical management of these patients.

Cutaneous presentation of disseminated histoplasmosis as a solitary peri-anal ulcer. Case report and discussion.

Disseminated histoplasmosis has a diverse and non‐specific range of clinical signs and symptoms. In a significant minority of patients, cutaneous lesions are apparent at the time of initial presentation, affording an opportunity to establish the diagnosis from a skin biopsy. The most frequently reported clinical scenario in immunocompromised patients with cutaneous involvement is that of multiple papulo‐nodular lesions on the face, trunk or extremities. The following report features an immunocompetent patient who presented with a solitary ulcerated plaque on the buttocks close to the anal verge. This case presentation underscores the broad spectrum of clinical presentations as well as the potential for diagnostic confusion with protozoa such as Leishmania or Trypanosoma species during histopathologic examination if special stains for fungal organisms are not performed.