Disseminated cutaneous B-cell lymphoma mimicking pseudolymphoma over a period of six years.

We describe a patient with a disseminated nodular cutaneous B-cell lymphoma, whose diagnosis was finally made after a long series of biopsies in different institutions in Europe and the United States. The differential diagnosis between lymphoma and pseudolymphoma was the recurrent problem throughout the patient's history because histologic and immunophenotypic criteria alone were not sufficient for differentiation. Molecular biology inconsistently detected clonal immunoglobulin rearrangements, which proves that careful clinicopathologic correlation remains mandatory. In contrast to a claimed "high-grade" malignant histology, this lymphoma responded with remission to PUVA therapy combined with intralesional corticosteroids, which is uncommon in the management of cutaneous B-lymphomas

Optical investigations to avoid the disturbing influences of furrows and wrinkles quantifying penetration of drugs and cosmetics into the skin by tape stripping

Furrows and wrinkles, as typical structures of human skin, represent a reservoir for topically applied substances. This reservoir can influence penetration experiments of topically applied substances into the stratum corneum by tape stripping. Optical methods such as laser-scanning microscopy, optical coherent tomography, and the microscopical investigation of histological sections obtained by biopsies were used to check a special protocol, which avoids these potential disturbances. The use of a transparent adhesive film with high flexibility and the realization of an intense contact to the stretched skin by pressing the tape with a roll, moved laterally on the tape, are the prerequisites to obtain correct data. The application of this experimental technique and the performance of tape stripping allow the determination of the horny layer profile and the local distribution of topically applied substance, undisturbed by the characteristic structure of the natural skin. These results demonstrate that the presented tape stripping procedure is a valuable tool to determine, quantitatively, the penetration and the bioavailability of drugs and cosmetics inside the human stratum corneum, in relation to the horny layer profile. © 2005 Society of Photo-Optical Instrumentation Engineers

Analysis of VH genes rearranged by individual B cells in dermal infiltrates of patients with mycosis fungoides

In patients with cutaneous T cell lymphomas such as mycosis fungoides B cells can frequently be detected in the lymphocytic dermal infiltrate. To analyse their immunoglobulin heavy chain gene repertoire, single B cells were obtained from tissue sections of two typical patients with mycosis fungoides using hydraulic micromanipulation followed by specific amplification of the respective gene segments by single-cell polymerase chain reaction (PCR) technique. A total of 21 VHDJH genes was sequenced. From each individual B cell a single productive VHDJH rearrangement was obtained. There was no clonal relationship detected between any of these rearrangements suggesting polyclonality of the infiltrating B cells. The representation of VH families was in accordance with the germ-line complexity. A remarkably high number of VH genes (5/13 in patient 1; 3/8 in patient 2) was completely or nearly germ-line-identical. Five of seven VH4 family genes were nearly unmutated. On the other hand, most of the VH3 gene family members were somatically mutated in an antigen-driven manner. The proportion of germ-line-identical VH genes, the usage of individual VH, D, JH gene elements, and the pattern of somatic mutations found in the B cells infiltrating skin lesions of patients with mycosis fungoides resembles the peripheral blood repertoire, suggesting a bystander role of these cells