Significance of Serum Calcitonin Gene-Related Peptide Levels in Prostate Cancer Patients Receiving Hormonal Therapy

Abstract

Background: Calcitonin gene-related peptide (CGRP) is one of the neuroendocrine markers. The serum CGRP levels in untreated prostate cancer (PCa) patients reportedly reflect the tumor volume and aggressiveness. However, the detailed evaluation of the serum CGRP levels in the PCa patients treated with hormonal therapy (HT) has never been reported. We measured the serum CGRP levels in PCa patients receiving HT to elucidate its clinical significance. Materials and Methods: We used serum samples from 129 PCa patients. Thirty-six patients had never received any treatment, and 93 had been treated with HT. The serum CGRP was measured by immunoradiometric assay, and we analyzed the correlation between the serum CGRP level and the clinicopathological factors. Results: The serum CGRP levels in the patients with higher clinical stages and histological grades were significantly higher than in those with lower stages and grades. Although in the patients treated with HT, the serum CGRP levels significantly correlated with clinical stage, these levels did not correlate with histological grade and the kind of HT. The highest serum CGRP level was observed in the stage D1 and stage D2 patients, not in the stage D3 patients treated with HT. Conclusion: The serum CGRP levels were significantly elevated in the PCa patients with high grade or high stage. However, in PCa patients receiving HT, various clinical factors influence the CGRP levels. Thus, evaluation of the levels should be careful.