ECTS Abstracts (2015) 1 P84

Prevalence of primary hyperparathyroidism in patients with prostate cancer

Francesco Minisola1, Alessandro Sciarra1, Magnus von Heland1, Stefano Salciccia1, Alessandro Gentilucci1, Jessica Pepe2, Cristiana Cipriani2, Sara Belcastro2, Emanuela Anastasi3, Sara Piemonte2, Luciano Nieddu4 & Salvatore Minisola2

1Department of Gynecology-Obstetrics and Urology, “Sapienza” University of Rome, Rome, Italy; 2Department of Internal Medicine and Medical Disciplines, “Sapienza” University of Rome, Rome, Italy; 3Department of Molecular Medicine, “Sapienza”; University of Rome, Rome, Italy; 4UNINT-Rome University of International Studies, Rome, Italy.

The prevalence of primary hyperparathyroidism (PHPT) in patients with prostate cancer has not been investigated. We consecutively enrolled 69 men (aged 51-87) with histologically confirmed prostate cancer (31 were candidate to radical prostatectomy, radiotherapy or hormone therapy, HT; 7 were in active surveillance and 31 already had radical prostatectomy while on HT). Eight patients had skeletal metastases. After clinical evaluation, we measured serum PSA (total and ratio), chromogranin A, S-100, ionised calcium, parathyroid hormone, 25(OH)D, bone alkaline phosphatase, collagen type I C-terminal cross-linked telopeptide, intact and C terminal fibroblast growth factor (FGF) 23. The protocol was approved by the “Sapienza” University of Rome Ethics Committee. We found a high prevalence of PHPT among cancer patients (n=9, 13%). We stratified the population on the basis of Gleason Score (GS) [≤7(3+4) and ≥7(4+3)], PSA (<4 ng/ml, between 4 and 10, and >10) and HT (yes/no) and used a generalised linear model with a logit link to predict the probability of developing PHPT. The model showed that only GS, C-terminal FGF-23 and HT had a significant effect (p<0.05). After controlling for other variables, we observed that the rise in FGF-23 increases the odds of developing PHPT by 2% (p<0.02), and higher values of GS are associated with a higher probability of developing PHPT (log-odds=3.6, p <0.01). Conversely, higher GS in association with HT play a significant protective role (p<0.01), decreasing the odds of developing PHPT by 8%. The prospective investigation shows a remarkable prevalence of PHPT in men with prostate cancer. The multivariate analysis demonstrates that more aggressive prostate cancer, as determined by GS, is a significant predictor of increased risk of PHPT, suggesting a possible causative relationship rather than a simple association between the two disorders. A thorough biochemical evaluation of mineral metabolism parameters is therefore mandatory in patients with prostate cancer.

Disclosure: The authors declared no competing interests.