San Diego, CA—Bone mineral density testing is underutilized in women with BRCA mutations who undergo risk-reducing salpingo-oophorectomy (RRSO). In a review of health surveillance data from a single institution, only about half of these women were screened for osteoporosis using dual-energy x-ray absorptiometry (DEXA) scan, despite being at significantly increased risk for the disease, said Emily Prendergast, MD, at the 2016 meeting of the Society of Gynecologic Oncology. The review also demonstrated that significant bone loss is common and develops rapidly following RRSO in women who carry the BRCA mutation.
“We need to do a better job determining how to better counsel these women who have BRCA mutations and undergo the risk-reducing surgery,” said Dr Prendergast, a second-year fellow at Cedars-Sinai Medical Center, Los Angeles, CA. “We do an absolutely great job at telling them how to reduce their cancer risk, but then we don’t adequately prepare them for what comes after that. It was interesting to find out that a lot of our own providers didn’t know what to do as far as screening goes.”
Significant Bone Loss Seen
The retrospective review was conducted of 192 women who carried the BRCA1/2 mutation and who underwent RRSO at Cedars-Sinai. Forty-six percent of the women had breast cancer, and 28% had exposure to either chemotherapy, a selective estrogen receptor modulator (SERM), or an aromatase inhibitor. The primary outcome was the number of women who had a DEXA scan following RRSO.
At a median follow-up of 6.5 years from the date of surgery, DEXA scanning was performed in 97 (51%) women following RRSO, of which 48 patients had ≥1 tests. Age, preoperative menopausal status, use of hormone replacement therapy (HRT), and length of follow-up were comparable between those who had DEXA scans and those who did not.
Fifty-eight (60%) of the women had osteopenia and 19 (20%) had osteoporosis. The median time to abnormal bone density was 24 months. Ten (5%) patients suffered fracture.
Thirty-five (46%) women who underwent DEXA surveillance used HRT. Compared with women who did not use HRT, those who did had lower frequencies of osteopenia (74% vs 83%, respectively) and osteoporosis (.06% vs 22%, respectively), although this difference did not achieve significance (P = .09).
Outcomes were no different between patients exposed to chemotherapy, SERMs, or aromatase inhibitors and those not exposed.
In women <50 years, osteopenia and osteoporosis were present in 66% and 11%, respectively, compared with 50% and 31% in postmenopausal women (P = .08). “The osteopenia rate was high even in women who were premenopausal. The median age difference between the premenopausal and the postmenopausal group was 15 years, but they had similar bone profiles,” said Dr Prendergast. “To me, it spoke volumes to the fact that oophorectomy probably played a huge role in that, and we didn’t do a very good job at prevention.”
Screening Guidelines Needed
Underscreening the population of BRCA carriers who undergo RRSO may, in part, be attributed to the lack of guidelines that address this at-risk group, she said. “A lot of providers extrapolate screening guidelines from the US Preventive Services Task Force or the National Osteoporosis Foundation, which doesn’t take into account oophorectomy at all and how that might weigh in,” she said.
Formation of such guidelines awaits prospective data elucidating bone loss in a larger population of BRCA carriers following RRSO. Until then, it would not be unreasonable to recommend a baseline DEXA scan at 24 months after surgery, Dr Prendergast said, based on these data and other data obtained from women who have oophorectomy to reduce their risk of breast cancer.
Prendergast EN, Green M, Zakhour M, et al. Bone density testing underutilized in BRCA population following risk-reducing salpingo-oophorectomy. Presented at: 47th Annual Meeting of the Society of Gynecologic Oncology; March 19-22, 2016; San Diego, CA. Abstract 22. www.sgo.org/wp-content/uploads/2016/03/SGO_2016-AM_Abstracts_FINAL2.pdf. Accessed March 29, 2016.