RESUMO
Anaplastic large cell lymphoma (ALCL) is classified as a CD30 positive non-Hodgkin lymphoma. Systemic ALCL (S-ALCL) is further subdivided into two subgroups based on anaplastic lymphoma kinase (ALK) expression. In systemic ALCL, positive ALK expression correlates with a favorable prognosis, whereas negative ALK expression correlates with poorer overall survival. By definition, primary cutaneous ALCL (cut-ALCL) is limited to the skin and is uniformly ALK-negative. Cut-ALCL closely resembles LyP with regards to its benign clinical course and CD30 positivity. We describe a unique case of ALK-negative (ALK-) S-ALCL presenting with cutaneous disseminated dome-shaped papules.
Assuntos
Linfoma Anaplásico de Células Grandes/enzimologia , Linfoma Anaplásico de Células Grandes/patologia , Receptores Proteína Tirosina Quinases/análise , Pele/patologia , Quinase do Linfoma Anaplásico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Medula Óssea/patologia , Ciclofosfamida/administração & dosagem , Dexametasona/administração & dosagem , Diagnóstico Diferencial , Evolução Fatal , Humanos , Linfócitos/patologia , Linfoma Anaplásico de Células Grandes/diagnóstico , Linfoma Anaplásico de Células Grandes/tratamento farmacológico , Linfoma Anaplásico Cutâneo Primário de Células Grandes/diagnóstico , Linfoma Anaplásico Cutâneo Primário de Células Grandes/enzimologia , Linfoma Anaplásico Cutâneo Primário de Células Grandes/patologia , Masculino , Pessoa de Meia-Idade , Terapia de Salvação , Neoplasias Cutâneas/enzimologia , Neoplasias Cutâneas/patologiaRESUMO
BACKGROUND: Aberrant expression of microRNAs (miRNAs) has been implicated in oncogenesis of various tumors and primary cutaneous T cell lymphomas. Dicer, a ribonuclease III-like enzyme is essential for miRNA processing. OBJECTIVE: We initiated a retrospective study to characterize the alterations in the expression profile of Dicer in patients with primary cutaneous T cell lymphomas (CTCL). METHODS: A total of 50 consecutive patients with primary CTCL were studied, with the majority having mycosis fungoides (n=34). Five patients had primary cutaneous CD 30+ anaplastic large cell lymphoma, four patients each had lymphomatoid papulosis and primary cutaneous CD4-positive small/medium T-cell lymphoma, one primary cutaneous γδ T cell lymphoma, one Sézary syndrome and another subcutaneous panniculitis-like T cell lymphoma of αß-phenotype. Immunohistochemistry was performed on paraffin sections using a commercially available antibody against Dicer. Intensity of expression was correlated with clinical parameters including disease specific survival (DSS) and time to progression (TTP). RESULTS: After a median follow-up of 74 months (range: 1-271), 12/50 patients (24%) have died. Univariate and multivariate analysis for disease-specific survival showed Dicer expression and stage as a negative predictive factor in the sole group of MF patients (n=34) as well as in the heterogeneous group of patients (n=50), but not gender, histological subtype, primary localization of disease, age and recurrence of lymphoma (p>0.05). CONCLUSION: Our data suggest Dicer expression as a possible molecular marker in patients with MF and apparently indicate that miRNA(s) might be of clinical relevance in CTCL.