BONE-MARROW AND PERIPHERAL-BLOOD INVOLVEMENT IN MANTLE CELL LYMPHOMA

The peripheral blood smears. bone marrow aspirates and biopsies of 46 patients with mantle cell lymphoma were reviewed. The diagnosis of man tle cell lymphoma was established in all cases on extramedullary tissu e samples using standard morphologic, phenotypic and molecular genetic criteria, 27/35 patients (77%) had circulating lymphoma cells (median 20% of all circulating white blood cells; range 5-90%) identified by morphology at some point during the course of their disease. No statis tical difference in survival was detected in patients with or without peripheral blood involvement. Lymphoma was identified in bone marrow a spirate specimens from 33/40 patients (83%) and in bone marrow biopsy specimens from 39/43 patients (91%). The pattern of marrow biopsy invo lvement was nodular (31 cases: 82%), interstitial (19 cases; 50%), par atrabecular (17 cases, 45%) and diffuse (12 cases; 32%). Although the median survival of patients with greater than or equal to 50% bone mar row involvement was 13 months, and the median survival of patients wit h less than or equal to 50% was 49 months, no statistically significan t differences between these small subgroups were observed. Mantle cell lymphoma frequently involves the peripheral blood and bone marrow. It s appearance is distinctive but variable, and immunophenotypic studies as well as morphologic confirmation by a biopsy of tissue other than bone marrow is still required for diagnosis.