[Splenic marginal zone B-cell lymphoma with epidermotropic skin involvement]. / Linfoma B esplénico de la zona marginal con afectación cutánea epidermotropa.

Marginal zone B-cell lymphoma (MZL) is subclassified into extranodal MZL of mucosa-associated lymphoid tissue (including cutaneous lymphomas), splenic MZL, and nodal MZL. We report the case of a 68-year-old man with erythematous-violaceous plaques and nodules. Skin biopsy showed an epidermotropic lymphocytic infiltration and cytology and immunohistochemistry were consistent with MZL. The workup revealed disease in the peripheral blood and bone marrow and massive splenomegaly. Splenectomy confirmed the diagnosis of splenic MZL and led to resolution of the skin lesions. Cutaneous recurrence was treated successfully with chemotherapy and rituximab but caused fatal hepatitis due to hepatitis B virus reactivation. Skin involvement by splenic MZL is uncommon; this form of the disease can present epidermotropism, a very rare finding in primary cutaneous MZL. Treatment consists of splenectomy, which may be associated with chemotherapy and/or rituximab; this treatment may lead to reactivation of latent hepatitis B infection and screening for hepatitis should therefore be performed prior to starting therapy.

[Primary cutaneous CD30+ lymphoproliferative disorders]. / Síndrome linfoproliferativo CD30+ cutáneo primario.

CD30+ lymphoproliferative disorders are the most common group of cutaneous T-cell lymphomas after mycosis fungoides and its subtypes. This group includes lymphomatoid papulosis and CD30+ anaplastic large-cell lymphoma; these 2 entities are the extremes of a spectrum with numerous intermediate varieties in which it is not possible to establish a clear diagnosis based on clinical and histopathologic criteria. CD30+ lymphoproliferative disorders must be differentiated from other lymphoproliferative diseases with CD30+ cells in the tumor infiltrates, such as mycosis fungoides or Hodgkin disease, and also from other inflammatory conditions or nonhematological neoplasms that can include this cell type, such as pityriasis lichenoides et varioliformis acuta or certain mesenchymal tumors (CD30+ pseudolymphomas). In contrast to their systemic homologues, which arise in the lymph nodes, CD30+ lymphoproliferative disorders generally have a good prognosis. It is very important to exclude the presence of a lymphoma of systemic origin with extralymphatic spread, as the prognosis and treatment are different.