Background Women with breast cáncer (BC) are at risk for the development of bone loss and osteoporosis (OP) mainly due to adjuvant therapies. Aromatase inhibitors (AI) therapy fully suppresses estrogen synthesis, further exacerbating the increased bone resorption and leading to an excess fracture risk. Thus, a close monitoring of bone mineral metabolism is recommended.

Objectives The aim of the present study was to analyze bone health status and clinical characteristics of women BC referred by oncologist to a specialized clinic and their outcomes during follow-up.

Methods Retrospective analysis of consecutive female patients with recent BC and low bone mineral density (BMD) referred to the osteoporosis outpatient clinic for assessment, as agreed with oncologists. A descriptive analysis of epidemiological, clinical, laboratory, imaging, and dual energy x-ray absorptiometry (DEXA) data is presented, both at baseline and last visit. 95% confidence intervals (95% CI) were estimated for rate of fragility fractures (FF) at baseline and during follow-up.

Results A total number of 156 female patients have been assessed up to January 2017; median aged 60.7 (SD±10.6) years old, 89% postmenopausal. BC was mainly non-methastasic (117; 75%), and 110 (70%) patients were on aromatase inhibitors (14 on anastrozole, 89 on letrozole, and 7 on exemestane). 36 patients (23%) were active smokers, and 17 (11%) had stopped smoking. At baseline, 37 patients (24.2%, 95CI% 20–37) had previous FF, mostly vertebral (19) or non-vertebral (13), and three cases had suffered from multiple FF. BMDs were at osteoporotic range at the lumbar spine (median T-score -2.6 p25/75 -2.2, -3.2) and osteopenic at both the femoral neck and hip (mediant T-score -1.9 p25/75 -1.1, -2.3). Regarding antiosteoporotic therapies, bisphosphonates were prescribed in 110 cases (70.5%), denosumab in 24 (15.3%), and raloxifene in two cases (1.2%); in the others (12.8%) only calcium plus vitamin D supplementation was recommended. A total of 107 patients were followed a median of 2.13 years (p25–75 1.23–3.18). During follow-up, new FF occurred in 13 patients (12.1%, 95% CI 6–19), that were vertebral in 8, non-vertebral in 4, both in one case, while no hip FF were detected.

Conclusions outcomes of a structured assessment of female patients with BC and low BMD are reported here. Despite this, 12% of cases developed a new FF, highlighting the need for special attention to this singular, secondary form of osteoporosis.

Disclosure of Interest None declared