Redefining bone metastasis imaging in breast cancer: whole body low-dose computed tomography compared with skeletal
Lipton Mitra1, Ankur Goyal2, Nivedita Kundu3
1Departments of Surgical Disciplines.
Background:
Skeletal scintigraphy is standard imaging to detect bone metastasis in breast cancer. Nuclear medicine facilities are limited in availability. As an alternative diagnostic modality, we evaluated whole-body low dose computed tomography (WBLDCT) scan for detection of bone metastasis.
Methods:
This cross-sectional exploratory study was conducted from November 2021 to May 2023 with an aim to study the clinical applicability of WBLDCT for detecting bone metastasis in patients with breast cancer. Patients with primary tumor measuring 5 cm or more, pathologically proven axillary lymph node metastasis, Stage III/IV disease, symptoms attributable to metastasis and suspected disease recurrence were included. Patients underwent WBLDCT and bone scan within 2 weeks. WBLDCT was done during the same time as conventional dose CT scan done as part of metastatic workup. Image analysis was performed by radiology and nuclear medicine experts in blinded fashion. Agreement amongst WBLDCT, bone scan and combination of these was calculated using inter-rater agreement.
Results:
One hundred seven patients underwent WBLDCT and bone scan. The mean age was 48.5 years and three-fourth had Stage III disease. Both bone scan and WBLDCT detected bone metastasis in 19 patients. Bone scan picked up additional metastasis in two patients. WBLDCT detected bone metastasis additionally in three patients. Specificity of bone scan and WBLDCT was 87.5 and 91.7%, respectively. Concordance rate of bone scan and WBLDCT with the combination was 0.889 and 0.945, respectively.
Conclusion:
WBLDCT can be used as an alternative imaging modality to detect bone metastasis in breast cancer patients.
