Incidence of low bone mineral density in patients with advanced prostate cancer before hormonal manipulation

Abstract

Background: Prostate cancer is the second most commonly diagnosed cancer in men with an estimated 1.3 million cases diagnosed in 2018 according to the most recent International Agency for Research on Cancer (IARC) report.A large proportion of men still present with advanced disease and in this situation androgen deprivation therapy (ADT) is the mainstay of treatment.Prostate cancer is largely androgen-dependent and responds to endocrine therapy. ADT is an effective treatment modality which decreases the rate of disease progression, alleviates symptoms, and prolongs patients’ survival. ADT can be achieved through surgery (i.e., bilateral orchidectomy) or medical therapy (gonadotropin releasing hormone agonists, antagonists and antiandrogens).Methods: With the approval from institutional ethic committee, a case control study was planned at the urology outpatient department (OPD) at SMS Hospital from April 2019 to March 2020. Based on inclusion and exclusion criteria, 44 patients with newly diagnosed advanced prostate cancer and requiring hormone manipulation were enrolled in study. Age matched control (age±2 years) was selected from patients attending urology clinics with conditions other than prostate cancer. Ratio of cases and control was kept 1:1. Written consent was taken from all participants.Results: Total 88 patients were enrolled in study, 44 in each group. The age of patients ranged from 57 to 86 years among the case group and 55–85 among the control group. Mean age of cases was 65.24±6.8 and control was 64.98±7.6 years (p=0.25). Body mass index which is calculated with standard formula (weight in kg/height in meter square) was significantly high among controls (24.20±2.46) in comparison to cases (23.42±2.84). Statistically significant difference was observed among case and control groups for PSA (p=0.0001) and serum calcium (p=0.005) however difference for alkaline phosphatase (ALP), parathyroid hormone (PTH) and vitamin D was found insignificant (p>0.05).Conclusions: Low bone mineral density in patients with advanced prostate cancer before hormonal manipulation is nearly 50%. PSA and serum calcium level were significant different among case and control however this difference was not found for ALP, PTH and vitamin D. Consideration should be given to performing BMD studies in these men before initiating treatment, to avoid or minimize potential bone-related complications in these patients.