[Reticulosis of the skin - a heterogenic group of diseases].

In terms "reticulosis of the skin" has been used preferentially in the German dermatological literature to designate an autonomous, irreversible, atypical, systemic proliferation of elements of the reticulohistiocytic system in the skin, different from mycosis fungoides, reactive hyperplasias (pseudolymphoma), true neoplasias (reticulo sarcoma) and storage dermatosis (histiocytosis X). They provide about 1/4 of the lymphoreticular proliferations of the skin, a frequency which is comparable with that of cutaneous T-cell-lymphomas (mycosis fungoides and Sézary's syndrome). Enzymecytochemical demonstration of hydrolytic enzymes, immunological (surface-markers for B- and T-lymphocytes, quantitative determination of tissue immunoglobulins) and electron-microscopic studies in 266 patients with lymphoreticular proliferations in the skin (65 of these were "reticuloses") have lead to the following results: 1. Most of the "reticulosis of the skin" belong to the B-cell lymphomas of low grade malignancy. 2. In the skin they show a typical histomorphological feature (B-cell-pattern of infiltrate). 3. Following the Kiel Classification further differentiation into centrocytic (36%), "immunocytic" (32%), centroblastic/centrocytic (18%) and lymphocytic (14%) lymphoma can be made. 4. "Skin-reticuloses" may represent early changes of malignant lymphoma and may precede late manifestation of systemic involvement for many years.