Opportunistic Evaluation of Bone Mineral Density By Pet-Ct in Hodgkin Lymphoma Patients

Abstract

Objective: Bone density loss and increased risk for osteoporosis are of concern in Hodgkin lymphoma (HL) patients. Routinely performed positron emission tomography-computed tomography (PET-CT) scans could be informative in assessing bone mineral density (BMD). Methods: This retrospective study included 80 adults with newly diagnosed HL treated with standard first-line chemotherapy regimens. PET-CT scans performed at diagnosis (PET-CT1), at the end of chemotherapy (PET-CT2), and at follow-up after remission (PET-CT3) were used to assess BMD changes by measuring lumbar vertebrae CT attenuation. A CT attenuation threshold of 160 Hounsfield units was used to define abnormal BMD. Results: Following chemotherapy, comparison of PET-CT2 with PET-CT1 revealed a mean (standard deviation) 14.2% (10.4%) BMD reduction (P<.001). On PET-CT3 performed at 14.6 (3.25) months after the last course of chemotherapy, a slight improvement (4.6% [10.4%]) in comparison to PET-CT2 was noted. Twelve patients (15%) converted from normal baseline BMD on PET-CT1 to abnormal BMD after chemotherapy on PET-CT2. Age, baseline BMD, and steroid cumulative dose were associated with BMD decline and risk for abnormal BMD after chemotherapy. No clinical fractures were reported, and only one rib fracture was incidentally captured (1.25%). Conclusion: HL patients treated with common first-line chemotherapies demonstrate a significant decline in bone density on routine PET-CT scans. Opportunistic use of PET-CT scan has the potential to detect HL patients at high risk for developing osteoporosis and to guide clinicians regarding monitoring and intervention. Abbreviations: BMD = bone mineral density; CT = computed tomography; DXA = dual-energy X-ray absorptiometry; HL = Hodgkin lymphoma; HU = Hounsfield units; L = lumbarvertebra; PET-CT = positron emission tomography-computed tomography; T = thoracic vertebra.