Change of serum prostate specific antigen values after radiation therapy in prostate cancer

Han, Tae Suk; Kim, Hyung Jin

Abstract

We studied the change or serum prostate specific antigen in 12 men of prostate cancer including 9 or stage C and 3 or stage D1 to monitor patients with adenocarcinoma of the prostate after radiation therapy. All patients had a pre-treatment prostate specific antigen level above 100ng/ml Median patient followup was 18 months (range 9 to 28 months) and serum prostate specific antigen levels were determined at 1 month and then 3 to 6 month intervals after radiation therapy. Initially, all patients had a decrease in prostate specific antigen within 6 months after treatment. Of 10 patients who had a decreasing prostate specific antigen to normal values, 1 patient had an increasing prostate specific antigen value at 21 months but 2 patients, a decrease in prostate specific antigen that never approaches normal had an increasing prostate specific antigen values at 12 months and 18 months. 3 patients(clinical stage D1/poorly differentiated ; 2 cases, clinical stage C/poorly differentiated; 1 case) who had an increasing prostate specific antigen values had a bone metastases. These observations indicate that patients who had a decreasing prostate specific antigen to normal values were low risk in disease progression and an increasing prostate specific antigen values after radiation therapy were correlated with progression to metastatic disease. We concluded that serial post-irradiation prostate specific antigen values may be useful in the early identification ofrecurrence and disease progression after radiation therapy for prostate cancer.