RT-PCR for PSA as a prognostic factor for patients with clinically localized prostate cancer treated with radiotherapy.
OBJECTIVE
To study prospectively the prognostic significance of the reverse transcriptase-polymerase chain reaction (RT-PCR) assay for patients with prostate cancer treated definitively with external beam radiotherapy. The RT-PCR assay for prostate-specific antigen (PSA) has been used to detect circulating prostate cancer cells in the serum of patients with prostate cancer.


METHODS
In prospective fashion, serum RT-PCR testing was performed before and/or after definitive therapy, with the results scored as positive or negative. The results were analyzed for 161 patients, and the RT-PCR result was correlated with the treatment outcome.


RESULTS
The median follow-up was 29 months. The pretreatment RT-PCR result was not predictive of biochemical relapse-free survival (bRFS) or clinical disease-free survival (DFS). Of 25 patients with T3-T4 tumors, those with a negative pretreatment RT-PCR result had better bRFS and a trend was noted toward better DFS compared with those with a positive result. Among patients with Gleason score 8 to 10 tumor who underwent pretreatment testing (n = 19), those with a negative RT-PCR result had better bRFS and DFS compared with those with a positive result. A trend toward better bRFS was seen for patients with negative versus positive post-treatment RT-PCR results. The DFS was better for patients with negative versus positive post-treatment RT-PCR results.


CONCLUSIONS
RT-PCR, when obtained before radiotherapy, may be predictive of outcome for patients with more advanced stages or higher Gleason scores. Post-treatment testing predicted for clinical relapse. Additional study is needed before RT-PCR is used regularly in clinical practice.
Gewanter
Richard M
RM
Department of Radiation Oncology, Columbia University College of Physicians and Surgeons, New York, New York 10032, USA.
Katz
Aaron E
AE
Olsson
Carl A
CA
Benson
Mitchell C
MC
Singh
Arun
A
Schiff
Peter B
PB
Ennis
Ronald D
RD
D000726:Androgen Antagonists / Q000627:therapeutic use; D017024:Chemotherapy, Adjuvant / Q000379:methods; D018572:Disease-Free Survival; D006801:Humans; D008297:Male; D009364:Neoplasm Recurrence, Local / Q000097:blood / Q000175:diagnosis; D009367:Neoplasm Staging; D009360:Neoplastic Cells, Circulating / Q000737:chemistry; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood / Q000175:diagnosis / Q000473:pathology / Q000532:radiotherapy*; D011879:Radiotherapy Dosage; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods*
D000726:Androgen Antagonists; D017430:Prostate-Specific Antigen