Role of bone marrow biopsy in staging of patients with classical Hodgkin's lymphoma undergoing positron emission tomography/computed tomography

Several studies suggested that staging bone marrow biopsy (BMB) could be omitted in patients with classical Hodgkin's lymphoma (cHL) when a positron emission tomography/computed tomography (PET/CT) is performed at baseline. To address the concordance between BMB and PET/CT in the detection of bone marrow involvement (BMI) and the BMB role in determining the Ann Arbor stage, we retrospectively collected data on 1244 consecutive patients with cHL diagnosed from January 2007 to December 2013. One thousand eighty-five patients who had undergone both BMB and PET/CT were analyzed, comparing the Ann Arbor stage assessed with PET/CT only to that resulting from PET/CT combined with BMB. One hundred sixty-nine patients (16%) showed at least one focal skeletal lesion (FSL) at PET/CT evaluation. Only 55 patients had a positive BMB (5.1%); 34 of them presented at least one FSL at PET/CT. To the contrary, 895 out of 1030 patients with a negative BMB did not show any FSL (86.9%). Positive and negative predictive values of PET/CT for BMI were 20 and 98%, respectively; sensitivity and specificity were 62 and 87%, respectively. Fifty-four out of 55 patients with a positive BMB could have been evaluated as an advanced stage just after PET/CT; only one patient (0.1%) would have been differently treated without BMB. Our data showed a very high negative predictive value of PET/CT for BMI and a negligible influence of BMB on treatment planning, strengthening the recent indications that BMB could be safely omitted in cHL patients staged with PET/CT.