Bone marrow biopsy in diffuse large B-cell lymphoma: useful or redundant test?

To determine the additional value of bone marrow biopsy (BMB) in the standard staging work-up of patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL), in terms of risk assessment and treatment planning.

A total of 113 consecutive patients with newly diagnosed DLBCL who had undergone standard pretreatment evaluation, including serum lactate dehydrogenase measurement, Eastern Cooperative Oncology Group performance status assessment, computed tomography or (18)F-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography, and BMB, were retrospectively included. National Comprehensive Cancer Network International Prognostic Index (NCCN-IPI) score and treatment strategy were determined in each patient, once without and once with taking into account BMB results. Numbers and percentages of BMB-induced changes on NCCN-IPI-based risk stratification (i.e. formation of low, low-intermediate, high-intermediate, and high risk groups) and choice of treatment were calculated, along with 95% confidence intervals (CIs).

BMB was positive in 18 of 113 patients (15.9%, 95% CI 10.2-23.9 %). BMB-induced changes on NCCI-IPI-based risk stratification occurred in 9 of 113 patients (8.0%, 95% CI 4.1-14.6%). Five patients were upstaged from low-intermediate to high-intermediate risk, and four patients were upstaged from high-intermediate to high risk. BMB findings changed treatment planning in none of the 113 patients (0.0%, 95% CI 0.0-4.0%).

Although BMB results upstaged the NCCN-IPI-based risk stratification in a small number of cases, this did not have any therapeutic implications in our patient series. These findings support the omission of BMB from routine staging of newly diagnosed DLBCL in the current risk stratification and treatment era.