Primary cutaneous centrofollicular lymphoma with a good response to radiotherapy.

Primary cutaneous lymphomas have different clinical behavior and prognosis than systemic lymphomas of similar histological subtype. About 30% of non-Hodgkin lymphomas involve extranodal tissues, the skin being the second most affected body organ after the gastrointestinal tract (approximately 18%). According to the EORTC (European Organization for Research and Treatment of Cancer) classification, the lymphoma centrofollicular is indolent, since the lesions increase in size slowly over the years and spread to extracutaneous sites is uncommon.

Isomorphic phenomenon of Koebner: facts and controversies.

Heinrich Koebner (1838-1904) presented in a meeting in 1872 and reported in 1877 the emergence of psoriatic lesions following trauma to healthy skin areas of patients with psoriasis. Since then, the Koebner phenomenon has been the subject of research, as it offers a unique opportunity in the investigation of the disease, especially in experimental studies, when this dermatosis may be observed in all its phases. Establishing the differences between Koebner, Wolf, Renbök, reverse Koebner, pseudo-Koebner phenomena, and pathergy is sometimes unclear.