Impact of Thyroid Hormones on Serum Prostate Specific Antigen Level in Patients with Benign Thyroid Disorders

Objective: The aim of the present study was to evaluate whether thyroid hormone levels in benign thyroid disorders resulting in hypothyroidism or hyperthyroidism had an impact on the levels of serum prostate specific antigen (PSA). Materials and Methods: A total of 50 male patients aged between 40 and 75 years who had newly diagnosed benign thyroid disorders were enrolled in this study. Patients with hypothyroidism (n=19) were enrolled as group 1 and patients with hyperthyroidism (n=31) as group 2. Before the initiation of medical treatment, levels of serum total, free PSA, and thyroid hormones were measured. Patients then received appropriate medical treatment for their thyroid disease. Once patients were noted to have achieved normal thyroid function tests in the second month following treatment initiation, serum total and free PSA levels were once again measured. Results: The mean age of the patients was 56.7 years. The mean pretreatment serum total PSA levels in group 1 and 2 were 1.5 and 2.6 ng/mL, respectively (p=0.03). Although group 1 patients had lower posttreatment mean serum total PSA levels (1.7 ng/mL) compared to group 2 (2.5 ng/ mL), the difference was not statistically significant (p=0.15). In the comparisons of pre and posttreatment serum total PSA, free PSA and free/total PSA (%) levels in both groups, no statistically significant difference was found (p>0.05). Conclusion: Our results showed that decreased serum thyroid stimulating hormone and increased serum T3 and T4 levels were associated with increased serum PSA levels. It was also observed that there was no alteration in serum PSA level in relationship to medical treatment received.