Incidence and Risk Factors of Bone Marrow Involvement by Non-Hodgkin Lymphoma
Janejira Kittivorapart MD*, Yingyong Chinthammitr MD*
Affiliation : * Division of Hematology, Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
Background : Since trephine bone marrow biopsy is an invasive procedure, the identification of a subgroup of patients with
Non-Hodgkin lymphoma (NHL) who have a minimal risk of bone marrow involvement would be helpful. This study is aimed
to determine the incidence of bone marrow involvement (BMI) by NHL and the predictors of no BMI to not only avoid this
invasive procedure but also decrease the cost of investigation.
Material and Method: Data from 320 patients with NHL at division of hematology between January 2008 and June 2009
were reviewed and analyzed.
Results : The cell types of NHL were classified as B-cell in 283 patients (88.4%), T-cell in 37 patients (11.6%) and incidence
of BMI is 24.4% and 18.9% in B- and T-cell, respectively. Factors significantly associated with BMI in univariate analysis
were the hepatic and splenic involvement (p = 0.03 and < 0.01, respectively), significant weight loss (p = 0.02), presence of
lymphadenopathy (LN) below diaphragm (p = 0.02), anemia (p = 0.001), low percent of blood neutrophil (p < 0.001), high
percent of blood lymphocyte (p < 0.001), low absolute neutrophil count (p = 0.002), high absolute lymphocyte count (p =
0.045), low platelet count (p < 0.001), high LDH (p = 0.026), and high alkaline phosphatase (p = 0.020). On the multivariate
analysis, factors associated with BMI included LN below diaphragm, anemia, low percent of blood neutrophil and low platelet
count. Excluding Burkitt lymphoma and mantle cell lymphoma, NHL patients with no LN below diaphragm, no hepatic &
splenic involvement, no significant weight loss, hemoglobin (Hb) >11 g/dL and platelet > 150,000/uL had BMI in 3/78
(3.8%).
Conclusion : The incidence of bone marrow involvement in NHL is 23.8%. Excluding Burkitt lymphoma and mantle cell
lymphoma, NHL patients with no LN below diaphragm, no hepatic & splenic involvement, no significant weight loss, Hb >
11 g/dL and platelet >150,000/uL had low risk of BMI.
Keywords : Bone Marrow, Non-Hodgkin Lymphoma
