The role of molecular analysis in cutaneous lymphomas.

Dec 2012

Deonizio JM, Guitart J.

Source

Department of Dermatology, Northwestern University, Chicago, IL.

Abstract

The purpose of this review is to summarize the most important molecular techniques for the diagnosis of cutaneous lymphomas. When making a diagnosis, we are looking for the solid clinicopathological correlation. Molecular analysis includes immunophenotyping and clonality analysis, and is important for 2 principal reasons: (1) to confirm the diagnosis in cases where the clinical and/or pathological presentations are nondiagnostic, and (2) to further characterize the nature of the lymphoma. More specifically, we are trying to discern whether the lymphoma is primarily cutaneous or systemic with secondary skin involvement, and we are also attempting to subclassify the tumor. Recently, many techniques have provided a more accurate diagnosis of cutaneous lymphomas and some prognostic implications, including polymerase chain reaction, fluorescence in situ hybridization, and flow cytometry. Fluorescence in situ hybridization is not routinely used in the diagnosis of cutaneous lymphoma, but many studies have shown potential future applications in various areas. Other techniques, such as comparative genomic hybridization, are still confined to the research arena, but have added some insight into the molecular pathogenesis of cutaneous T-cell lymphoma.

PubMed

A case of recurrent pseudolymphomatous folliculitis: A mimic of cutaneous lymphoma

A case of recurrent pseudolymphomatous folliculitis: A mimic of cutaneous lymphoma
J Am Acad Dermatol. 2009 Jun

Kwon EJ, Kristjansson AK, Meyerson HJ, Fedele GM, Tung RC, Sellheyer K, Tuthill RJ, Honda KS, Gilliam AC, McNiff JM.

Department of Dermatology, Case Western Reserve University, Cleveland, Ohio, USA.

Pseudolymphomatous folliculitis is a rare entity. We present a 62-year-old man with a recurrent solitary nodule on his nose requiring multiple excisions. Microscopic examination of the excisions showed a dense lymphocytic infiltrate containing numerous histiocytes and S100+, CD1a+ dendritic cells that surrounded and infiltrated hypertrophic hair follicles. Diffuse sheets of CD3+ T cells and nodular clusters of CD20+ B cells were also seen. There was normal reactive pattern of follicular centers. Light chain restriction was not detected. T-cell receptor and immunoglobulin heavy chain gene rearrangements by polymerase chain reaction revealed negative findings. A diagnosis of pseudolymphomatous folliculitis was made based on the hypertrophic hair follicles, periadnexal S100+ and CD1a+ dendritic cells, and negative clonal gene rearrangement study findings. This case of recurrent pseudolymphomatous folliculitis is instructive because of the resemblance to cutaneous lymphomas and cutaneous lymphoid hyperplasias, and the need for correct diagnosis to avoid overtreatment of this indolent condition.

Elsevier/ScienceDirect

Lymphomatoid papulosis in childhood: six case reports and a literature review

Lymphomatoid papulosis in childhood: six case reports and a literature review
Ann Dermatol Venereol. 2008 Oct

Bories N, Thomas L, Phan A, Balme B, Salameire D, Thurot-Guillou C, Dalle S.

Service de dermatologie, hôpital Hôtel-Dieu, 1 place de l'Hôpital, Lyon cedex 02, France.

BACKGROUND: Lymphomatoid papulosis (LyP) is a rare lymphoproliferative disorder. It is now included in the World Health Organisation (WHO) classification of cutaneous lymphomas. Although frequently described in adults, there have been only a few reported cases of LyP in children; diagnosis is often difficult in this population and no clear guidelines have been established regarding management or monitoring. In this article we report six new cases of LyP in children.

PATIENTS AND METHODS: This is a retrospective study of six children, aged between two and 11 years, seen at the Hôtel-Dieu Hospital in Lyon and at the Grenoble Hospital Centre between 2005 and 2008. Each child underwent skin biopsy for histological and immunohistochemical analysis.

RESULTS: All six children presented papulonodular lesions on the limbs and trunk, in some cases necrotic, present for different times and developing in episodes. Histology and immunolabelling announces in all six cases militated in favour of LyP type A, with large CD30+ and CD15- cells dispersed in an inflammatory dermal infiltrate made up for the most part of lymphocytes, polynuclear neutrophils, eosinophils and a small number of histiocytes.

DISCUSSION: Only around 60 cases of LyP have so far been reported in children, principally type A. Association with malignant lymphoma occurs, with high risk in relation to the general population of the same age. Clinical diagnosis is confirmed histopathology and immunolabelling. There is currently no consensus regarding therapeutic management. First-line treatment generally comprises therapeutic abstention or dermal corticosteroids. Methotrexate and phototherapy constitute possible alternatives but should be used only in very disseminate or debilitating forms of the disease.

CONCLUSION: The presentation and course of LyP of childhood differs very little from the adult form. Cases of associated lymphoma have been reported. Although regular clinical monitoring is recommended, there is no call for routine laboratory testing.

EMConsulte