Pruritic cutaneous lesions mimicking dermatitis artefacta in the course of mediastinal gray-zone lymphoma

Unlike nodular sclerosis Hodgkin lymphoma (NSHL) and primary mediastinal B-cell lymphoma (PMBL) that are common types of lymphomas present in the mediastinum, mediastinal gray-zone lymphoma (MGZL) is extremely rare [1]. These tumours are called “gray zone” because of their overlapping morphological and immunophenotypic features [2]. In the case of MGZL, the surface immunoglobulin is not expressed, there is at least one B-cell marker expressed and the presence of other cell surface markers varies. These tumours can exhibit prominent expression of CD20, CD79a with a weaker or absent expression of CD15 and CD30 or vice versa. The minimum immunohistochemical panel, essential for establishing a correct diagnosis, includes CD20, PAX5, MUM1, CD30, CD15, and EBV by in situ hybridization. MGZL may present in one patient the PMBL-like morphology and NSHL-like immunophenotype or vice versa [3, 4]. Historically, these tumours were classified as “anaplastic large-cell lymphoma Hodgkin’s-like” [5].
MGZLs predominantly affect young men. MGZL is often present as a single mass in the mediastinum that grows to large sizes [6]. As a consequence it can cause chest pain, breath difficulties, fatigue or weight loss. The aetiology has not been well defined, although certain genetic mutations have been implicated. In recently published studies, the epigenetic profiles of these neoplasms are suggested to be crucial for the confirmation of diagnosis [3, 7]. According to Eberle et al., prediction of MGZL can be made on the basis of DNA methylation profiles (including such genes as HOXA5, MMP9, EPHA7, DAPK1) [7]. Their rarity and recent identification have led to uncertainty regarding the therapeutic strategy, clinical characteristics and treatment. NSHL and PMB are treated differently; therefore, the optimal treatment for gray zone lymphoma is unclear [8]. The condition is reported to have a poorer prognosis than both primary mediastinal large B-cell lymphoma and classical Hodgkin’s lymphoma [9].
To our knowledge, this is the first report about cutaneous lesions in the course of MGZL which were treated as dermatitis artefacta.
A 19-year-old woman presented with a 6-month history of intense pruritus followed by the eruption of erythematous papules on the lower and upper extremities (Figures 1–3). Pruritus exacerbated at night (after warming up of the body) and after a hot bath.
About 1 month after the onset of the...


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