Search

Background: Pachyderma is defined as severely thickened skin with deep folds and is occasionally observed with primary cutaneous NK and T-cell lymphoma (pCNKTCL), primary cutaneous B-cell lymphoma (pCBCL), and leukemia cutis (LC). Aim: To describe the clinical, histological, and therapeutic particularities of a series of pCNKTCL, pCBCL, and LC patients with pachyderma. Results: In a series of pCNKTCL (n = 70), pCBCL (n = 12), and LC (n = 2) patients followed up during 9 years, 6 cases of pachyderma were observed. Pachyderma occurred on the arms (n = 2), thighs (n = 1), forehead (n = 1), and face (n = 2). The mean age of the patients was 69 years (51–82). The stages were erythrodermic (T4) mycosis fungoides (MF) (n = 1), folliculotropic MF (FMF) (n = 2), classic (T2) MF (n = 2), and chronic myeloid leukemia (n = 1). The erythrodermic MF patient with acute pachyderma on the right arm responded rapidly to oral steroids. The other cases were indolent, appeared progressively, and were highly treatment resistant. Histology revealed dense dermal neoplastic infiltration. The immunohistological profile of the pachydermic lesions was similar to common MF and LC. Conclusion: Pachyderma is an atypical manifestation of MF and LC and may occur on the face (FMF) or the extremities (MF). The rapidly appearing pachyderma may be transitory and responds readily to oral steroids.

Pediatric Degos disease is rare, with only 36 cases reported in the medical literature. Classically the diagnosis has been established according to pathognomonic histopathologic findings, but when these features are not present, there may be a delay in diagnosis. We report the second congenital case of Degos disease, highlighting the clinical and dermoscopic findings.

Context.—Acral lentiginous melanoma is the most prevalent clinical presentation of melanoma in ethnic groups other than whites and also occurs in significant numbers in North America and Europe. Despite a clear-cut clinical picture, histologic findings seen in partial biopsies may be too subtle and deceive pathologists dealing with such cases. Objectives.—To make pathologists aware of the histologic findings during early phases of acral lentiginous melanoma (including the in situ phase), to compare those findings with what is seen in acral junctional nevus, and to highlight their similarities and differences. This review will also emphasize the important clinical and dermatoscopic findings to be considered when diagnosing acral lentiginous melanoma. Data Sources.—Review of published articles on the epidemiology; the clinical, dermatoscopic, and histopathologic findings; and the molecular biology of acral lentiginous melanoma as well as the personal experience of the authors when dealing with such cases. Conclusions.—Acral lentiginous melanoma is a clinicopathologic entity with a clear-cut clinical picture: a diameter larger than 0.7 mm; ill-defined, darkly pigmented, flat lesion with irregular borders on acral locations; and the presence of mostly single-cell proliferations of melanocytes along the dermo-epidermal junction. Along with a few additional criteria, these findings should be sufficient to allow the pathologist to make the diagnosis and to recommend complete excision. Fluent communication between clinician and pathologist will facilitate a correct diagnosis.