Bone densitometric assessment and management of fracture risk in Indian men of prostate cancer on androgen deprivation therapy: Does practice pattern match the guidelines?

Fracture risk and assessment in adults with cancer

Individuals with cancer face unique risk factors for osteoporosis and fractures. Clinicians must consider the additive effects of cancer-specific factors, including treatment-induced bone loss, and premorbid fracture risk, utilizing FRAX score and bone mineral densitometry when available. Pharmacologic therapy should be offered as per cancer-specific guidelines, when available, or local general osteoporosis guidelines informed by clinical judgment and patient preferences. Our objective was to review and summarize the epidemiologic burden of osteoporotic fracture risk and fracture risk assessment in adults with cancer, and recommended treatment thresholds for cancer treatment-induced bone loss, with specific focus on breast, prostate, thyroid, gynecological, multiple myeloma, and hematopoietic stem cell transplant. This narrative review was informed by PubMed searches to July 25, 2022, that combined terms for cancer, stem cell transplantation, fracture, bone mineral density (BMD), trabecular bone score, FRAX, Garvan nomogram or fracture risk calculator, QFracture, prediction, and risk factors. The literature informs that cancer can impact bone health in numerous ways, leading to both systemic and localized decreases in BMD. Many cancer treatments can have detrimental effects on bone health. In particular, hormone deprivation therapies for hormone-responsive cancers such as breast cancer and prostate cancer, and hematopoietic stem cell transplant for hematologic malignancies, adversely affect bone turnover, resulting in osteoporosis and fractures. Surgical treatments such as hysterectomy with bilateral salpingo-oophorectomy for gynecological cancers can also lead to deleterious effects on bone health. Radiation therapy is well documented to cause localized bone loss and fractures. Few studies have validated the use of fracture risk prediction tools in the cancer population. Guidelines on cancer-specific treatment thresholds are limited, and major knowledge gaps still exist in fracture risk and fracture risk assessment in patients with cancer. Despite the limitations of current knowledge on fracture risk assessment and treatment thresholds in patients with cancer, clinicians must consider the additive effects of bone damaging factors to which these patients are exposed and their premorbid fracture risk profile. Pharmacologic treatment should be offered as per cancer-specific guidelines when available, or per local general osteoporosis guidelines, in accordance with clinical judgment and patient preferences.

Osteoporosis-Related Health Behaviors in Men With Prostate Cancer and Survivors: Exploring Osteoporosis Knowledge, Health Beliefs, and Self-Efficacy

This descriptive study aimed to (a) determine the extent of osteoporosis knowledge, perceived health beliefs, and self-efficacy with bone healthy behaviors in men with prostate cancer and survivors and (b) identify how dietary bone healthy behaviors are associated with these psychobehavioral and psychosocial factors. Three different questionnaires were used to measure osteoporosis knowledge, health beliefs, and self-efficacy in a group of men with prostate cancer and survivors. Bone health was assessed via dual-energy X-ray absorptiometry and calcium intake using a diet history. The prevalence of osteoporosis and low bone mass was high at over 70%. Participants had inadequate osteoporosis knowledge with a mean score of 43.3% ( SD = 18%) on the Facts on Osteoporosis Quiz. Participants scored low on the subscale measuring barriers to exercise (median = 11; interquartile range [IQR] = 6.5), indicating minimal barriers to exercise participation, and the subscale measuring the benefits of exercise scored the highest (median = 24; IQR = 3.5) compared with the other subscales. Men with prostate cancer and survivors were highly confident in their exercise and calcium self-efficacy (83.0%, IQR = 24.0% and 85.7%, IQR = 27.0%, respectively). Participants did not meet their calcium requirements or consume enough dairy products for optimum bone health. Men with prostate cancer and survivors have poor osteoporosis knowledge, but are confident in their self-efficacy of undertaking bone healthy behaviors. This confidence did not translate to specific dietary behaviors as they did not meet their calcium or dairy intake requirements. Implications for cancer survivors is that there is a need for bone health education programs among prostate cancer survivors. These programs should go beyond education and empowerment to provide practical guidance to maximize uptake of bone healthy behaviors.

Prevalence of osteoporosis in prostate cancer survivors: a meta-analysis

Androgen deprivation therapy (ADT), which is used in the treatment of prostate cancer (PCa), is associated with increased morbidity. Severe bone loss is a major consequence of androgen ablation and with an increasing number of patients undergoing this treatment, the incidence of osteoporosis and fractures can be expected to increase with a significant impact on healthcare. To evaluate the prevalence of osteoporosis, we conducted a review of the literature on bone health in men with PCa undergoing ADT. A meta-analysis was conducted using the quality effects model, and sources of heterogeneity were further explored by consideration of discordant effect sizes of included studies in the meta-analysis and examining reasons thereof. Our analyses indicate that the prevalence of osteoporosis varies between 9 and 53 % with this variation partially explained by treatment duration, disease stage, ethnicity and site of osteoporosis measurement. While it is well known that a rapid decline in bone health amongst men with PCa on ADT occurs, this meta-analysis documents the high prevalence of osteoporosis in this population and reinforces the need of preventative approaches as part of usual care of PCa patients.

Optimal bone health management strategies in patients with prostate cancer

Bone health is affected in patients with prostate cancer, both by the disease and its treatment. Metastases to bone leads to pain, fractures, and spinal cord compression; bone loss due to androgen deprivation therapy (ADT) leads to osteoporosis and its complications. Both these scenarios are a major cause of morbidity and adversely affect the quality of life of these patients. Maintaining an optimum bone health throughout the natural course of prostate cancer is an important aspect in the management of this disease. An understanding of the complex interplay between osteoclasts, osteoblasts, receptor activator of nuclear factor κB (RANK), and various other tyrosine kinases involved in the pathophysiology of bone metastases is essential. Zoledronic acid (ZA), an intravenously administered bisphosphonate, and Denosumab, a subcutaneously administered inhibitor of nuclear factor B ligand (RANKL), have already been approved by Food and Drug Administration (FDA) for their use in treatment of bone metastases. This article discusses the pathophysiology of bone metastases and bone loss due to ADT in prostate cancer, role of biomarkers, newer modalities of imaging, World Health Organization (WHO)/FRAX nomogram in evaluation of these patients, utility of currently available drugs and evidence supporting their use, and newer therapeutic agents like alpha-emitting Radium-223, endothelin-A receptor antagonists (Atrasentan and Zibotentan) and the proto-oncogene tyrosine-protein kinase (SRC) inhibitor, Dasatinib.