Plasmocytomes cutanés primitifs multiples

Resume Introduction Les plasmocytomes cutanes primitifs (PCP) sont une forme rare de lymphome B cutane. Nous en rapportons un nouveau cas. Observation Un homme de 51 ans, sans antecedent notable, consultait devant l'apparition progressive, en deux ans, de plaques erythemateuses, papulo-nodulaires et infiltrees, sur l'ensemble du corps. L'analyse histologique d'une biopsie cutanee posait le diagnostic de plasmocytome cutane multiple, dont les explorations paracliniques permettaient d'affirmer le caractere primitif. L'abstention therapeutique etait decidee compte tenu du caractere primitif de l'atteinte cutanee et de l'absence de gene fonctionnelle. Il n'y a pas eu d'evolutivite apres quatre ans de surveillance reguliere. Discussion Le plasmocytome cutane primitif (PCP) est issu d'une proliferation clonale plasmocytaire uniquement cutanee. Les PCP multiples sont tres rares et ont ete traites dans la plupart des cas par de la chimiotherapie associee ou non a de la radiotherapie. Leur pronostic est mauvais, la survie a deux ans etant de 25 %. Cette observation est originale car c'est a notre connaissance la seule ou l'abstention therapeutique a ete suivie d'une absence d'evolutivite avec un recul de quatre ans. Il existe donc des formes peu evolutives de PCP ne justifiant pas d'emblee d'une chimiotherapie. ________________________________________ Summary Background Primary cutaneous plasmacytoma is a rare form of cutaneous B-cell lymphoma. Patients and methods A 51 year-old male with an unremarkable history gradually presented erythematous papulonodular lesions that had appeared gradually over the whole body throughout a two-year period and showing histologic and immunohistochemical features of cutaneous plasmacytoma. Staging investigations confirmed the primary character of the disease, and because of this and the absence of functional impairment, we opted for therapeutic abstention. No progression was noted after 4 years of regular monitoring. Discussion Primary cutaneous plasmacytoma (PCP) is characterized by clonal proliferation of plasma cells in skin. Multiple PCPs are extremely rare and to date have been treated in most cases by chemotherapy, either with or without radiotherapy. The prognosis is poor, with 2-year survival of only 25%. The present case is original, being the only one to our knowledge in which therapeutic abstention was followed by a lack of progression after 4 years of regular follow-up. Consequently, certain indolent forms of PCP do not warrant automatic institution of chemotherapy. Mots cles " Plasmocytome cutane multiple; " Traitement; " Abstention Keywords " Primary cutaneous plasmacytoma; " Treatment; " Therapeutic abstention