Monitoring of prostate-specific antigen during external beam radiotherapy for carcinoma of the prostate.
In 35 patients with histologically confirmed carcinoma of the prostate confined to the pelvis, the value of prostate-specific antigen (PSA) was evaluated during external beam radiotherapy to the prostate and draining pelvic lymph nodes. In eleven patients initial prostate-specific antigen levels were more than 10 ng/ml and in twelve patients between 4 and 10 ng/ml. In the remaining twelve, initial prostate-specific antigen levels were less than 4 ng/ml. In the course of radiotherapy we could see a significant decrease of the prostate-specific antigen, even in those with levels between 4 and 10 ng/ml. This decrease seems to follow a logarithmic course but, because only three measurements during radiotherapy were made, this needs further study. With higher levels (more than 20 ng/ml), we rarely saw a value of less than 10 ng/ml at the end of radiotherapy but had to wait for several months for lower values to be reached. In several cases prostate-specific antigen decrease took up to three months after the end of the radiation course. Our results indicate that prostate-specific antigen values actually start decreasing during the radiation course itself and may, therefore, be useful for monitoring response to radiotherapy.
van Eijkeren
M
M
Department of Radiotherapy and Nuclear Medicine, University Hospital, Gent, Belgium.
van Haelst
J P
JP
D000135:Acid Phosphatase / Q000097:blood; D000368:Aged; D000369:Aged, 80 and over; D000951:Antigens, Neoplasm / Q000032:analysis*; D014408:Biomarkers, Tumor; D002277:Carcinoma / Q000175:diagnosis / Q000276:immunology / Q000532:radiotherapy*; D004796:Clinical Enzyme Tests; D006801:Humans; D008297:Male; D008875:Middle Aged; D015166:Monitoring, Immunologic; D008991:Monitoring, Physiologic; D011467:Prostate / Q000201:enzymology / Q000276:immunology*; D017430:Prostate-Specific Antigen; D011471:Prostatic Neoplasms / Q000175:diagnosis / Q000276:immunology / Q000532:radiotherapy*; D011879:Radiotherapy Dosage; D011882:Radiotherapy, High-Energy; D013997:Time Factors
D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D000135:Acid Phosphatase; D017430:Prostate-Specific Antigen