Morphometric vertebral fractures in patients with castration-resistant prostate cancer undergoing treatment with radium-223: a longitudinal study in the real-life clinical practice

Prediction of fragility fractures in men with prostate cancer under androgen deprivation therapy: the importance of a multidisciplinary approach using a mini-invasive diagnostic tool

Bone fragility in men who are treated with androgen deprivation therapy (ADT) has a complex pathophysiology that differs from that of primary and post-menopausal osteoporosis. Fracture risk assessment based on bone mineral density (BMD) and Fracture Risk Assessment Tool (FRAX) score might not be effective in this patient setting, since high frequency of fragility fractures has been reported even in subjects with low FRAX risk and normal BMD. In this paper we want to emphasize the importance in the individual assessment of bone fragility and prediction of fractures by measuring parameters of bone quality, assessing morphometric vertebral fractures and evaluating body composition that in subjects under hormone-deprivation therapies can play a crucial role. Noteworthy, a single mini-invasive diagnostic tool, i.e., the dual energy x-ray absorptiometry (DXA) scan, offers the opportunity to evaluate reliably parameters of bone quality (e.g., trabecular bone score) and body composition, besides measurement of BMD and assessment of vertebral fractures by a morphometric approach. This article highlights the values and cost-effectiveness of this mini-invasive tool in the context of multidisciplinary approach to subjects with prostate cancer under ADTs.

Prediction of vertebral fractures in cancer patients undergoing hormone deprivation therapies: reliability of who fracture risk assessment tool (frax) and bone mineral density in real-life clinical practice

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In females under estrogen-deprivation therapies, risk of vertebral fractures was associated with FRAX score for major fractures, with the best therapeutic threshold of 6.5%.

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In males under androgen-deprivation therapy, risk of vertebral fractures was high when BMD T-score was lower than −1.0 SD or when subjects were treated with abiraterone.

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High body mass index was an independent risk factor for vertebral fractures in males exposed to androgen-deprivation therapy.

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In the setting of hormonal deprivation therapies, FRAX and BMD thresholds were lower than those used in post-menopausal osteoporosis and primary male osteoporosis.

Background and Objective

Prediction of fractures in cancer survivors exposed to hormone-deprivation therapies (HDTs) is a challenge since bone loss is rapid and severe, and determinants of fractures in this setting are still largely unknown. In this study we investigated reliability of the WHO Fracture Risk Assessment Tool (FRAX) and bone mineral density (BMD) to identify subjects developing vertebral fractures during HDTs.

Design

Five-hundred-twenty-seven consecutive subjects (429 females with breast cancer, 98 males with prostate cancer; median age 61 years), under HDTs for at least 6 months, were evaluated for vertebral fractures by a radiological and morphometric approach, in relationship with FRAX score, body mass index (BMI), BMD, age and duration of HDTs.

Results

Vertebral fractures were found in 140 subjects (26.6%) and spine deformity index was significantly associated with duration of HDTs (rho 0.38; p < 0.001). Only in females, vertebral fractures were significantly associated with FRAX score for major fractures [OR 1.08; P < 0.001]. The best cut-off of FRAX score for major fractures, as calculated by receiving operating characteristic (ROC) analysis was 6.35%. In males, however, vertebral fractures were significantly and independently associated with BMI ≥ 25 Kg/m² (OR 17.63; P < 0.001), BMD T-score below −1.0 SD at any skeletal site (OR 7.79; P < 0.001) and gonadotropin-releasing hormone agonists (GnRHa) plus abiraterone treatment (OR 11.51; P = 0.001).

Conclusions

FRAX and BMD may be useful for predicting vertebral fractures in subjects undergoing HDTs, but the thresholds seem to be lower than those used in the general population. High BMI is a determinant of vertebral fractures in males under HDT.

Associations between osteoporosis and drug exposure: A post-marketing study of the World Health Organization pharmacovigilance database (VigiBase®)

BACKGROUND

Bone remodeling is a complex process, and many conditions (including drug exposure) lead to osteoporosis. Here, we sought to detect new disproportionality signals for drugs associated with osteoporosis.

METHODS

We performed a disproportionality analysis of the World Health Organization's VigiBase® pharmacovigilance database through April 12, 2020. The frequency of reports on osteoporosis for all identified drug classes was compared with that for all other drugs and quoted as the reporting odds ratio (ROR) [95% confidence interval (CI)].

RESULTS

Of the 7,594,968 cases spontaneously recorded to VigiBase®, 4758 concerned osteoporosis. New disproportionality signals with a pharmacologically plausible mechanism were found for drugs used in neurology (levodopa (ROR [95%CI]: 10.18 [4.33-25.10]), selective serotonin agonists (4.22 [2.34-7.00]) and memantine (4.10 [1.56-8.93])), hematology (romiplostim (4.93 [1.15-21.10])), pulmonology (macitentan (3.02 [1.84-4.90])), ophthalmology (ranibizumab (3.31 [1.00-10.51])) and rheumatology (tofacitinib (3.65 [3.00-4.40])). The robustness of these new results is supported by the significant RORs for the vast majority of drugs already known to induce osteoporosis and/or increase the fracture risk, namely glucocorticoids, gonadotropin-releasing hormone analogs, anti-aromatases, androgen receptor blockers, thyroid hormones, proton pump inhibitors, thiazolidinediones, vitamin K antagonists, loop diuretics, protease inhibitors, nucleoside and nucleotide reverse transcriptase inhibitors, and enzyme-inducing antiepileptics including barbiturates and derivatives, hydantoin derivatives, carboxamide derivatives and fatty acid derivatives.

CONCLUSION

We established up a comprehensive list of drugs potentially associated with osteoporosis and highlighted those with pharmacologically plausible mechanisms leading to bone fragility. Our results might pave the way for additional exploration of these mechanisms.

Skeletal health in patients with differentiated thyroid carcinoma

Osteoporosis and fractures are important comorbidities in patients with differentiated thyroid cancer (DTC), with potential negative impact on quality of life and survival. The main determinant of skeletal fragility in DTC is the thyrotropin (TSH)-suppressive therapy, which is commonly recommended to prevent disease's recurrence, especially in patients with structural incomplete response after thyroid surgery and radio-iodine therapy. TSH-suppressive therapy can stimulate bone resorption with consequent bone loss, deterioration of bone microstructure and high risk of fragility fractures. The skeletal effects of TSH-suppressive therapy may be amplified when thyroid cancer cells localize to the skeleton inducing alterations in bone remodelling, impairment of bone structure and further increase in risk of fractures. The management of skeletal fragility in DTC may be challenging, since prediction of fractures is a matter of uncertainty and data on effectiveness and safety of bone-active agents in this clinical setting are still scanty. This review deals with pathophysiological, clinical and therapeutic aspects of skeletal fragility of patients with DTC.