Transrectal ultrasound in the diagnosis and staging of local disease after I125 seed implantation for prostate cancer.
A study was undertaken to assess the ability of transrectal ultrasound (TR/US), digital rectal examination (DRE), and Prostate Specific Antigen (PSA), to diagnose persistent prostate cancer following an I125 seed implant (SI). Twenty-six patients formed the study group. The median follow-up time was 38 months, and the range was 20 to 60 months. Eighty-eight percent (23/26) had suspicious lesions on TR/US, followed by ultrasound-guided biopsies. Biopsies were performed only on those patients having suspicious lesions on TR/US. Histologically proven adenocarcinoma was found in 81% (21/26) of the patients. Statistical evaluation was done using tissue obtained at biopsy as the "gold standard." The sensitivities for the DRE and PSA were 33% and 76%, respectively. The specificities for DRE and PSA were 50% and 0%, respectively. The positive predictive values for cancer were 91% by TR/US, 100% by DRE, and 89% by PSA. The negative predictive values were 13% for DRE and 0% for PSA. Overall detection rates (N = 26) were 81% for TR/US, 27% for DRE, and 62% for PSA. We conclude that ultrasound criteria for the presence of cancer are the same for both the post-irradiated prostate and the untreated prostate, and that TR/US is the most sensitive test for the diagnosis of persistent local cancer following I125 seed implantation.
Lee
F
F
Department of Radiology, St. Joseph Mercy Hospital, Ann Arbor, Michigan 48106.
Torp-Pedersen
S
S
Meiselman
L
L
Siders
D B
DB
Littrup
P
P
Dorr
R P
RP
Pauli
F J
FJ
D000368:Aged; D000951:Antigens, Neoplasm / Q000032:analysis; D001918:Brachytherapy; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis* / Q000473:pathology; D009367:Neoplasm Staging / Q000379:methods; D010173:Palpation; D017430:Prostate-Specific Antigen; D011471:Prostatic Neoplasms / Q000532:radiotherapy*; D012007:Rectum; D014463:Ultrasonography / Q000379:methods*
D000951:Antigens, Neoplasm; D007457:Iodine Radioisotopes; D017430:Prostate-Specific Antigen