[Polymyositis as a paraneoplastic syndrome in a case of non-Hodgkin lymphoma].

The authors describe the case of a patient with NHL, who had undergone a series of clinical and laboratory investigations for the presence of pain, oedema and functional deficiency of the lower limbs associated with generalized weakness. From the data of the literature in cases of myositis, labelled as paraneoplastic disorders, no histological classification or phenotypic characterization have been provided, with exception of a case diagnosed as K1 positive lymphoma. A meta-analysis of case control studies and cohort of myositis and neoplasia do not show an increased incidence of cancer before a diagnosis of polymyositis (PM), although it seems to be an increased risk following diagnosis. The association of PM with a neoplasia, compared with that of dermatomyositis (DM) with a neoplasia, seems less frequent. In view of these considerations, of the usefulness of a diagnosis of neoplasia concurrently or in association with a neoplasia with a PM/DM, and furthermore in order to better define the frequency of a particular phenotype in the subsequent lymphoproliferative disorders, we have described a case of polymyositis, admitted in one hospital and subsequently recognized as being associated with a diffuse follicular non-Hodgkin lymphoma with small B lymphocytes.