Biopsy after external beam radiation therapy for adenocarcinoma of the prostate: correlation with original histological grade and current prostate specific antigen levels.
We obtained post-irradiation biopsies in 37 men with initially stage T3 prostatic adenocarcinoma treated by external beam radiotherapy. Eligibility for post-irradiation biopsy included no clinical local failure, interval since treatment of 24 months or more and no endocrine therapy. Of the 37 patients 23 (62%) had negative biopsies while 14 (38%) had positive biopsies. Of 23 patients whose original cancer was well or moderately differentiated 18 (78%) had negative biopsies, compared to only 5 of 14 (36%) of those with poorly differentiated cancer (p less than 0.03). Among 19 patients whose current serum prostate specific antigen (PSA) value is less than 2.5 ng./ml. 15 (79%) had negative biopsies, compared to only 4 of 14 (29%) with a PSA level of greater than 2.5 ng./ml. (p less than 0.02). These results strongly suggest that there is a low probability of positive post-irradiation biopsy regardless of its significance in men with a normal prostate by palpation and a normal serum PSA value. However, short followup since biopsy precludes analysis of the predictive value of post-irradiation biopsy on long-term local and distant disease status.
Dugan
T C
TC
Department of Radiation Oncology, Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston.
Shipley
W U
WU
Young
R H
RH
Verhey
L J
LJ
Althausen
A F
AF
Heney
N M
NM
McManus
P L
PL
Abraham
E H
EH
D000230:Adenocarcinoma / Q000097:blood / Q000401:mortality / Q000473:pathology* / Q000532:radiotherapy; D000951:Antigens, Neoplasm / Q000097:blood*; D014408:Biomarkers, Tumor / Q000097:blood*; D001707:Biopsy, Needle; D003037:Cobalt Radioisotopes / Q000627:therapeutic use*; D006801:Humans; D015993:Life Tables; D008297:Male; D011467:Prostate / Q000000981:diagnostic imaging / Q000276:immunology / Q000473:pathology* / Q000528:radiation effects; D017430:Prostate-Specific Antigen; D011471:Prostatic Neoplasms / Q000097:blood / Q000401:mortality / Q000473:pathology* / Q000532:radiotherapy; D011867:Radioisotope Teletherapy; D011879:Radiotherapy Dosage; D013997:Time Factors; D014463:Ultrasonography
D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D003037:Cobalt Radioisotopes; D017430:Prostate-Specific Antigen