Will bone marrow biopsies be a thing of the past some day?...maybe

Here is a look at using PET/CT for detecting bone marrow involvement. They find that PET/CT always finds it but biopsy frequently misses it. This is hardly surprising since the biopsy can only take a sample from where the stick the needle in (the hip unusually). That is not much good if your bone marrow lymphoma is in a different bone. Maybe one day we will do away with BMB's altogether.


PET-CT staging of DLBCL accurately identifies and provides new insight into the clinical significance of bone marrow involvement.

Khan AB, Barrington SF, Mikhaeel NG, Hunt AA, Cameron L, Morris T, Carr R.

Source:
Department of Haematology, Guy's and St Thomas' Foundation Trust, London, United Kingdom.

Abstract:
We investigated whether positron emission tomography combined with computed tomography (PET-CT) identifies clinically important bone marrow involvement by diffuse large B-cell lymphoma (DLBCL) with sufficient accuracy to replace routine staging bone marrow biopsy. All patients from a single centre diagnosed as DLBCL since 2005 had data extracted from staging PET-CT, marrow biopsy, and treatment records. Of 130 patients, 35 (27%) were judged to have marrow involvement; 33 were identified by PET-CT compared with 14 by marrow histology. PET identified all clinically important marrow lymphoma, while biopsy did not upstage any patient. Sensitivity and specificity were 94% and 100% for PET-CT and 40% and 100% for marrow biopsy. As a secondary aim, we compared the prognosis of marrow involvement, as detected by PET-CT or biopsy. Cases with marrow deposits identified by PET-CT but not biopsy had progression-free survival (PFS) and overall survival similar to stage IV disease without involved marrow. Positive biopsy conferred significantly inferior PFS (P = .003); these cases frequently had other markers of poor-risk disease. These data confirm that in experienced hands PET-CT has a high level of accuracy for identifying marrow disease in DLBCL, and provide new insight into the nature and clinical significance of marrow involvement.

h/t Greg Dafoe