Korean J Clin Oncol.  2020 Jun;16(1):39-45. 10.14216/kjco.20007.

Risk of osteoporosis and fracture in long-term breast cancer survivors

• Go J
• Park S
• Kim KS
• Kang MC
• Ihn MH
• Yun S
• Kim SH
• Hong SH
• Lee JE
• Han SW
• Kim SY
• Kim Z
• Hur SM
• Lee J

• KMID: 2504532
• DOI: http://doi.org/10.14216/kjco.20007

Abstract

Purpose
High incidence of osteoporosis has been reported in breast cancer patients due to early menopause triggered by adjuvant treatment and temporary ovarian function suppression. In this study, we sought to determine whether long-term breast cancer survivors had an elevated risk of low bone density compared to the general population.
Methods
Long-term breast cancer survivors who had been treated for more than 5 years were selected for this study. Data were obtained from medical records and using a questionnaire from the Korea National Health and Nutrition Examination Survey (KNHANES). An agematched non-cancer control group was selected from the KNHANES records. Incidence of fracture and bone mineral density (BMD) were compared between the two groups.
Results
In total, 74 long-term breast cancer survivors and 296 non-cancer controls were evaluated. The incidence of fracture did not differ between the two groups (P=0.130). No differences were detected in lumbar BMD (P=0.051) following adjustment for body mass index, while hip BMD was significantly lower in breast cancer survivors (P=0.028). Chemotherapy and endocrine treatment were not related to low BMD in breast cancer survivors. In more than half of the survivors, the 10-year risk of osteoporotic fracture was less than 1%.
Conclusion
Long-term breast cancer survivors had low bone density but a comparable risk of fracture compared to non-cancer agematched controls. Further studies on the factors related to low bone density in long-term breast cancer survivors are required.

Keyword

Breast neoplasms; Survivorship; Osteoporosis; Osteoporotic fracture