Central nervous system involvement in non-Hodgkin's lymphomas: value of lumbar puncture as initial staging procedure.

To identify the subgroups of patients with malignant non-Hodgkin's lymphomas who might benefit from prophylactic therapy to prevent CNS relapse, lumbar puncture was routinely performed among the other staging procedures from January 1976 to October 1979 in 76 patients with diffuse lymphomas. The study also takes into consideration 32 patients who came to out observation during the same period and who were studied with lumbar puncture performed in case of suspicious CNS involvement or along with other procedures during restaging the acquire further information on prognostic factors related to CNS involvement. Cerebrospinal fluid (CSF) cytology was positive in 3 of 76 patients studied with initial lumbar puncture; however, only 2 (2.6%) were asymptomatic. Within the group of 32 patients in whom lumbar puncture was performed during the course of the disease, all 17 patients with suspicious CNS involvement were found to have a positive CSF cytology with the exception of 1 patients with multiple focal involvement of brain parenchyma. Clinical signs of CNS involvement associated with CNS positivity were all found in patients with diffuse histology. In these patients bone marrow invasion or a leukemic picture was frequently associated with CNS relapse. In 47% of patients CNS disease developed while they were in clinical remission. In this series cranio-spinal irradiation associated with intrathecal chemotherapy provided the best results, even in survival was not primarily dependent upon the control of their CNS involvement but related to progressive systemic disease in other sites. On the basis of the clinico-prognostic parameters examined, some guidelines for early diagnosis and treatment of CNS lymphomatous involvement are provided.