Opportunistic osteoporosis screening using routine computed tomography images to identify bone loss in gynecologic cancer survivors

Objective Cancer treatment-induced bone loss is a known side effect of cancer therapy. Computed tomography (CT) bone mineral density screening is a novel tool for identifying bone loss. This study aims to use routine CT images to determine long-term bone mineral density changes and osteoporosis risk among women with gynecologic cancers. Methods Bone loss was evaluated in a retrospective cohort of women <= 65 years old with gynecologic cancer who underwent oophorectomy from January 2010 to December 2014. Opportunistic CT-based bone mineral density measurements (Hounsfield units, HU) were performed at baseline and intervals up to 5 years after cancer diagnosis. Osteoporosis risk was categorized by HU. Bivariate and multivariate analyses were performed to compare baseline to follow-up bone mineral density at 1, 3, and 5 years and to identify predictors of bone loss following diagnosis. Results A total of 185 patients (median age 53 years, range 23-65 years, 78.1% ovarian cancer) were included. Bone mineral density significantly decreased between baseline and 1 year (p<0.001), 3 years (p<0.001), and 5 years (p<0.001). Half with normal bone mineral density at baseline had risk for osteopenia or osteoporosis at 5 years. Four percent had osteoporosis risk at baseline compared with 1 year (7.4%), 3 years (15.7%), and 5 years (18.0%). Pre-treatment bone mineral density was a significant predictor at 1 and 5 years (1 year: p<0.01; 5 years: p<0.01). History of chemotherapy predicted bone loss at 1 year (p=0.03). More lifetime chemotherapy cycles were associated with increased risk of osteoporosis at 1 year (p=0.03) and 5 years (p=0.01). Conclusions Women with gynecologic cancers may experience accelerated cancer treatment-induced bone loss. Routine CT imaging is a convenient screening modality to identify those at highest risk for osteoporosis who warrant further evaluation with dual-energy X-ray absorptiometry. Routine bone mineral density assessments 1 year following oophorectomy for cancer treatment may be warranted in this population.