PRIMARY CUTANEOUS MEDIUM AND LARGE-CELL LYMPHOMAS OTHER THAN MYCOSIS-FUNGOIDES - AN IMMUNOHISTOLOGICAL AND FOLLOW-UP-STUDY ON 54 CASES

Primary cutaneous medium and large cell lymphomas (MLCL) other than my cosis fungoides (MF) are rare, and their prognosis and treatment are c ontroversial. The clinical, immunohistological and follow-up data of 5 4 well-documented cases of primary cutaneous MLCL other than MF, seen in our institutions over a 14-year period, were retrospectively review ed, in order to determine the prognostic factors related to these lymp homas, and to analyse the results obtained with different treatment re gimens. Forty-six patients presented with a solitary tumour or with lo calized lesions, and eight had disseminated cutaneous lesions, Accordi ng to the updated Kiel classification, 45 cases (83%) corresponded to B-cell lymphomas: centroblastic lymphomas, 32 cases; centroblastic-cen trocytic lymphomas, 11 cases; immunoblastic lymphomas, two cases. Nine cases (17%) were classified as T-cell lymphomas: pleomorphic medium a nd large cell lymphomas, eight cases; anaplastic large cell lymphoma, one case. Four of eight patients with disseminated skin lesions had a T-cell lymphoma, whereas 41 of 46 patients with a solitary tumour had a B-cell lymphoma. Patients with disseminated skin lesions and elevate d serum lactate dehydrogenase (LDH) levels had a poor prognosis. Compa rison of patients' overall survival, depending on immunohistological s ubtype, showed that the median survival of patients with pleomorphic T -cell lymphoma was 2.5 years, whereas it was not reached at 12 years f or patients with centroblastic-centrocytic and centroblastic lymphoma. The eight patients with disseminated skin lesions were treated with p olychemotherapy. Most patients with a solitary tumour or with localize d lesions of low tumour bulk were treated by surgical excision or radi otherapy alone, and nine other patients with localized lesions of high tumour bulk were treated with initial polychemotherapy. Clinical pres entation (i.e. solitary or disseminated lesions), serum LDH levels, an d the immunohistological subtype, are important prognostic factors in cutaneous MLCL. Patients with disseminated skin lesions have a poor pr ognosis, and should be treated with intensive polychemotherapy regimen s, whereas those with a solitary tumour, or with localized lesions of low tumour bulk, are adequately treated by radiotherapy.