Fig 1.
Patient’s flowchart.
Table 1.
Characteristics of breast cancer patients.
Table 2.
Distribution of fractures by body region.
Fig 2.
Deming regression between CT attenuation at L1 vertebral body and DXA T-score.
Table 3.
Diagnostic performance of L1 vertebral attenuation on chest CT for osteoporosis defined as DXA T-score ≤-2.5.
Fig 3.
Kaplan–Meier survival curves for fracture-free survival in patients with breast cancer.
(A) For comparison, patients were divided into two groups based on the L1 CT attenuation at a 90 HU threshold. Fracture-free survival curves were estimated for each group (L1 attenuation > 90 HU, gray line; L1 attenuation ≤ 90 HU, black line). There was a significant difference in fracture-free survival between the two groups (P < .001). (B) Patients were divided into two groups based on the T-score obtained from dual-energy X-ray absorptiometry (DXA) at a -2.5 threshold for comparison. Fracture-free survival curves were estimated for each group (T-score >-2.5, blue line; T-score ≤-2.5, green line). There was a significant difference in fracture-free survival between the two groups (P < .001).
Fig 4.
Compression fracture in T8 vertebral body in a 61-year-old woman with breast cancer.
(A-B) Chest computed tomography (CT) scan showed a markedly decreased L1 trabecular attenuation in 2013 (73 HU, A) and 2014 (64 HU, B). (C-D) Dual-energy X-ray absorptiometry (DXA) was interpreted as osteopenia with a T-score of -2.0 in 2013 (C) and a T-score of -1.7 in 2014 (D). (E-G) Chest CT scan showed no fracture in 2013 (E). Sagittal CT scan (F) in 2014 and bone scan (G) showed a compression fracture in the T8 vertebral body. The diagnosis discrepancy between DXA and CT in this case suggests that DXA was falsely negative given the subsequently-identified fracture.
Table 4.
Cox proportional hazards model for fracture-free survival in patients with breast cancer.