Implications Of Circulating Chromogranin A In Prostate Cancer

Objective. To evaluate whether measurement of circulating chromogranin A (CgA) levels provides clinicopathological and prognostic information in prostate cancer. Material and methods. Plasma CgA levels were measured in 57 patients with histologically confirmed prostate cancer ( stage B or less, n = 22; stage C, n = 10; stage D1, n = 2; hormone-naive D2, n = 12; hormone-refractory D2, n = 11) and in 22 with undetected prostate cancer using an enzyme-linked immunoabsorbent assay. Results. Median plasma CgA levels were significantly higher in patients with prostate cancer than in those with undetected cancer ( p = 0.0271). Higher stage ( p<0.0001) and higher grade ( p = 0.0412) tumours were also significantly associated with higher plasma CgA levels. Above-normal CgA levels were also detected in 4/27 patients (15%) who underwent radical prostatectomy. Postoperative clinical failure was not reported in the prostatectomy patients; however, prostate-specific antigen (PSA) failure was reported in 44% of patients after a median follow-up period of 20.3 months. Multivariate analysis revealed that the pathological stage of the tumour was the only independent predictive variable for postoperative PSA failure ( p = 0.0494). Preoperative plasma CgA levels had no impact on postoperative PSA failure in the subgroup ( prostatectomy patients). Elevated plasma CgA levels were associated with a poor survival prognosis in patients with stage D2 prostate cancer after a median follow-up period of 22.5 months ( p = 0.0416). Conclusions. It was demonstrated in this study that plasma CgA levels in prostate cancer increase with the severity of the disease, especially for progressive hormone-refractory prostate cancer (HRPC), after hormone therapy. Although this cross-sectional study involved only a small number of patients, we believe that plasma CgA levels may effectively predict HRPC status and prognosis in metastatic cases.