RESUMEN
Immunocytomas represent low grade B cell lymphomas related to marginal zone lymphoma but with a predominance of cells having plasmacytic features. Eleven patients presented with lesions compatible with primary cutaneous immunocytoma. The expression of CD2, CD3, CD5, CD20, CD21, CD23, CD43, CD56, CD79, and bcl-2 was analyzed immunohistochemically and of lambda and kappa light chains by an in situ hybridization assay. There were 6 men and 5 women ranging in age from 43 to 76 years. The most common clinical presentation was as extremity based clustered erythematous brown papules. Therapy with local irradiation or Rituximab resulted in lesional resolution. Underlying illnesses included Sjögren's syndrome, hepatitis C, ulcerative colitis, autoimmune thyroid disease, and rheumatoid arthritis. Four patients were taking medications previously associated with immune dysregulation. In two patients in whom a paraproteinemia was uncovered. The most common pattern light microscopically was perivascular small lymphocytic and plasmacellular infiltrates mimicking architecturally a reactive process. Phenotypic studies revealed a marginal zone (MZL) phenotype amid the small atypical lymphocytic infiltrate and highlighted a reactive background population of non-neoplastic T and B cells; light chain restriction was seen amid the plasma cells. In one case there was EBER staining of plasma cells while in another case in whom there was hepatitis C seropositivity staining of plasma cells for hepatitis C associated RNA transcripts was observed. Primary cutaneous immunocytoma appears to arise from a pre-existing state of reactive lymphoid hyperplasia. latrogenic and endogenous immune dysregulation including in the context of lymphotropic viral infections is implicated.
Asunto(s)
Leucemia Linfocítica Crónica de Células B/patología , Neoplasias Cutáneas/patología , Adulto , Anciano , Antígenos CD/metabolismo , Femenino , Genes de Inmunoglobulinas , Hepacivirus/genética , Hepacivirus/aislamiento & purificación , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/aislamiento & purificación , Humanos , Inmunohistoquímica , Hibridación in Situ , Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/inmunología , Leucemia Linfocítica Crónica de Células B/virología , Masculino , Persona de Mediana Edad , Fenotipo , ARN Viral/genética , ARN Viral/aislamiento & purificación , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/inmunología , Neoplasias Cutáneas/virologíaRESUMEN
To investigate reliability of calculating percentage of myeloblasts by flow cytometric method, data were obtained from 74 hematologic patients (76 paired data). Myeloblast counts obtained by manual count versus flow cytometry were compared. Our data show that the percentage of myeloblasts in the bone marrow obtained with flow cytometric method correlates well with manual count (correlation coefficient is 0.9912). A very high correlation coefficient means that reliable percentage of myeloblasts in the bone marrow can be obtained by either method alone. Flow cytometry is a useful adjunct (or quality control) to validate manual myeloblast count and vice versa.