Outcome of Bone Marrow Biopsy in Patients with Diffuse Large B-Cell Lymphoma Patients Staged by Combined 18 FGD-PET/CT Scan

DLBCL represents 1/3 of non-Hodgkin lymphoma, in 60% of the cases the disease presented in advanced stage (III-IV). Extranodal organs are involved in 40% of cases; BM involvement in 11% to 27% of cases. BMB is an invasive procedure, & it also could represent false negative result in patients with patchy pattern of involvement or if involvement else where the routine biopsy site. Study included 102 patients, above the age of 18 years, confirmed to have newly diagnosed DLBCL with no any other malignancy. Every patient had a baseline PET-Ct, bone marrow biopsy. PET-CT detected BM infiltration in 23 patients, i.e 22.5%. BMB were positive in 20 patients, while PET-CT showed BM involvement in 23 patients.- 94 patients had concordant negative ( 75 patients ) or positive ( 19 patients), PET-CT & BMB results. One patient had positive BMB and negative PET-CT. All patients with stage I & II had concordant PET-CT & BMB results One patient graded stage III by PET-CT showed 1-2% BM infiltration & upstaged to stage IV. Of the 49 patients graded stage IV by PET-CT, 3 had positive BM involvement PET-CT and negative BMB. the sensitivity of PET-CT was 95%, the specificity of PET-CT was 96.2%. the PPV was 86.4% & the NPV was 98.7%. PET-CT showed 95.9% accuracy. Our results suggest PET-CT as a powerful tool to evaluate BM infiltration in patients with DLBCL, with overall concordance exceeding 94% (100%for stage I & II ). For patients with advanced stage IV disease, PET-CT was able to retrieve patients with BM involvement & false negative BMB.