Background: The bone marrow examination is an important Procedure in the
diagnosis of malignant lymphoma and in the initial staging of patients with malignant
lymphoma. The purpose of this study was to investigate the incidence and pattern of
the bone marrow involvelnent of malignant lymphoma. Also the discordance in the
morphology of lymphoma cells between lymph node and bone marrow was evaluated.
Methods: One hundred ninety four non-Hodgkin lymphoma cases and twenty two
cases of Hodgkin disease at Korea Cancer Center Hospitial from January 1991 to
August 1993 were examined. Peripheral blood smears, bone marrow aspiration smears
and biopsy sections of these cases were evaluated.
Results: The overall incidence of bone marrow involvement by non-Hodgkin
lymphoma was 28.9% and by Hodgkin disease was 27.2%. Diffuse large cell type was
most frequently seen in non-Hodgkin lymphoma(39.7%). The interstitial patters and
packed marrow pattern were most frequently observed in the bone marrow biopsy. The
subtypes of non-Hodgkin lymphoma which showed frequent bone marrow involvement
were follicular mixed type, lymphoblastic type, and small noncleaved cell type. Mixed
cellularity was most frequently seen in Hodgkin disease(59.1%). The rate of discordance
in the morphology of lymphoma cells between lymph node and bone marrow was 47.6%.
Conclusion: It would be necessary to examine the morphology of lymphoma cells and
the pattern of involvement in the marrow examination and further study on the
relationship between these factors and the prognosis of the patients would be necessary.

Keywords: Bone marrow involvement, Malignant lymphoma