Our results also indicate that measuring serum ferritin and/or total PSA levels can provide even higher sensitivity when testing elderly patients (> 65 years of age) with hyperferritinemia (serum ferritin > 400 ng/ml), which suggests that serum ferritin and total PSA levels may be particularly valuable for diagnosing prostate cancer in elderly men. The gene discussed is KLK3; the disease is isolated hyperferritinemia.