Younger women treated for uterine or ovarian cancer are at increased risk for decreased bone mineral density and osteoporosis, especially in the first year after diagnosis, and they should be screened for bone changes, investigators advise.
This recommendation is based on results from a retrospective study of women, age 65 years and younger, all of whom underwent oophorectomy and most of whom received chemotherapy. Half of the women who had normal bone mineral density (BMD) at baseline were at risk for osteopenia or osteoporosis 5 years after diagnosis.
Rates of patients at risk for osteoporosis roughly doubled each year for the first 3 years of follow-up, reported study author Janelle Sobecki, MD, of the University of Wisconsin–Madison, and colleagues.
Their research is detailed in an abstract that had been slated for presentation at the Society of Gynecologic Oncology’s Annual Meeting on Women’s Cancer. The meeting was canceled because of the COVID-19 pandemic.
“Clinicians should follow current National Comprehensive Cancer Network guidelines regarding bone mineral density screening in women under 65 years old with cancer who have undergone therapy affecting their ovarian function [ovarian removal and/or antiestrogen therapies],” Dr. Sobecki said in an interview.
“Our findings indicate women with gynecologic cancer undergoing ovarian removal and chemotherapy may warrant sooner bone density evaluation, as early as 1 year following treatment. Bone loss screening in this population is feasible using opportunistic CT imaging,” she added.
Current guidelines recommending routine BMD evaluation every 2 years in women who received treatments impairing ovarian function are based largely on data in breast cancer patients, but there is a paucity of data on women who undergo oophorectomy and cancer therapies, both of which are known risk factors for bone loss, Dr. Sobecki noted.
“Bone loss is an important issue for women’s cancer survivorship, particularly for women who we expect to have long survival,” she said. “Identifying bone loss early is important for long-term bone health and prevention of osteoporosis in cancer survivors.”
Patient analysis
To get a better picture of long-term BMD changes and osteoporosis risk in younger patients, Dr. Sobecki and colleagues conducted a retrospective cohort study of women with uterine or ovarian cancers who underwent oophorectomy from 2010 to 2015.
The investigators calculated CT-based L1 trabecular attenuation BMD measurements (Hounsfield units, HU) on CT scans performed at baseline and at 1 year, 3 years, 5 years, and beyond 5 years after cancer diagnosis.
Osteoporosis risk was defined based on HU. Less than 100 HU was deemed “concerning” for osteoporosis, 100-150 HU was suggestive of osteopenia, and more than 150 HU indicated normal BMD.
The investigators reviewed scans for 185 patients with a median age of 55 years and a mean body mass index of 32 kg/m2. Each patient had at least a baseline scan and one additional CT scan during follow-up.
The majority of patients (78.1%) had ovarian cancer, 78.1% underwent chemotherapy, and 17.1% were treated with external beam radiation. As of 2019, 118 patients (63.6%) were still alive.
Results and next steps
The investigators found that BMD decreased from a mean of 179.4 HU at baseline to 146.5 HU at 1 year, a significant decline (P < .001), and to 123.63 HU beyond 5 years (P < .001). As noted before, half of the patients with normal BMD at baseline were at risk for osteopenia or osteoporosis at 5 years.
The proportion of patients at risk for osteoporosis at baseline was 4.3%, compared with 7.4% at 1 year, 15.7% at 3 years, 18% at 5 years, and 23.3% beyond 5 years. BMD at baseline was a significant predictor for bone loss at all time points. In multivariate analysis, chemotherapy predicted bone loss at 1 year (P = .03), and current smoking predicted BMD decrease at 5 years (P < .01).
“We plan to further investigate the role of chemotherapy in bone loss in gynecologic cancer patients, including chemotherapy dose-related bone loss,” Dr. Sobecki said. “We also plan to investigate bone loss in older women [over the age of 65] undergoing treatment for gynecologic cancer as they may be at greater risk than their baseline age-related risk.”
This study was internally funded. Dr. Sobecki reported no conflicts of interest.
SOURCE: Sobecki J et al. SGO 2020, Abstract 130.