Comparison of Whole-Body MRI, CT, and Bone Scintigraphy for Response Evaluation of Cancer Therapeutics in Metastatic Breast Cancer to Bone

Abstract

Background: CT and bone scintigraphy have limitations in evaluating systemic anticancer therapy (SACT) response in bone metastases from metastatic breast cancer (MBC).Purpose: To evaluate whether whole-body MRI enables identification of progressive disease (PD) earlier than CT and bone scintigraphy in bone-only MBC. Materials and Methods:This prospective study evaluated participants with bone-only MBC between May 2016 and January 2019 (ClinicalTrials.gov identifier: NCT03266744). Participants were enrolled at initiation of first or subsequent SACT based on standard CT and bone scintigraphy imaging. Baseline whole-body MRI was performed within 2 weeks of entry; those with extraosseous disease were excluded. CT and whole-body MRI were performed every 12 weeks until definitive PD was evident with one or both modalities. In case of PD, bone scintigraphy was used to assess for bone disease progression. Radiologists independently interpreted images from CT, whole-body MRI, or bone scintigraphy and were blinded to results with the other modalities. Systematic differences in performance between modalities were analyzed by using the McNemar test.Results: Forty-five participants (mean age, 60 years 6 13 [standard deviation]; all women) were evaluated. Median time on study was 36 weeks (range, 1-120 weeks). Two participants were excluded because of unequivocal evidence of liver metastases at baseline whole-body MRI, two participants were excluded because they had clinical progression before imaging showed PD, and one participant was lost to follow-up. Of the 33 participants with PD at imaging, 67% (22 participants) had PD evident at whole-body MRI only and 33% (11 participants) had PD at CT and whole-body MRI concurrently; none had PD at CT only (P , .001, McNemar test). There was only slight agreement between whole-body MRI and CT (Cohen k, 0.15). PD at bone scintigraphy was reported in 50% of participants (13 of 26) with bone progression at CT and/or whole-body MRI (P , .001, McNemar test). Conclusion:Whole-body MRI enabled identification of progressive disease before CT in most participants with bone-only metastatic breast cancer. Progressive disease at bone scintigraphy was evident in only half of participants with bone progression at whole-body MRI.

Clinical Impact of FDG-PET/CT Compared with CE-CT in Response Monitoring of Metastatic Breast Cancer

“…On the other hand, whole body MRI revealed a comparable diagnostic accuracy to PET/CT regarding the detection of bone metastasis [13,38], and it has been shown that whole body MRI could detect the progression earlier than CE-CT in patients with boneonly MBC [39]. Therefore, whole body MRI could be considered as a potential alternative strategy in the response monitoring of MBC patients, while future prospective studies are needed to compare the clinical impact of all three modalities through comparable groups.…”

Lipid metabolism within the bone micro-environment is closely associated with bone metabolism in physiological and pathophysiological stages

“…ROS thereafter attacks the cell membrane and induces cell lysis and death. This is exacerbated by aging, where bone mass declines and lipid and cholesterol concentrations increase, especially in postmenopausal women [ 43 ]. When the bone marrow is saturated with lipids and cholesterol, it is more likely to experience an increase in ferroptosis.…”

Whole-body magnetic resonance imaging: technique, guidelines and key applications

“…The recent Response Evaluation of Cancer Therapeutics (RESPECT) study [75] monitored treatment response in a cohort of 44 women with metastatic BC using bone scintigraphy, CT and WB-MRI at 12-week intervals. Amongst the 33 patients who arrived at radiological progression during the study, all were seen with WB-MRI at time of first appearance of progression, but only 11 of these were evident on the CT of the corresponding time-point.…”