George Boris Rodrigues MD, Presenter: Nothing to Disclose

Fred Yoon, Abstract Co-Author: Nothing to Disclose

Jonathan Izawa, Abstract Co-Author: Nothing to Disclose

David D'Souza, Abstract Co-Author: Nothing to Disclose

Michael Lock, Abstract Co-Author: Nothing to Disclose

Donald Downey, Abstract Co-Author: Nothing to Disclose

To determine the prognostic value of trans-rectal ultrasound (TRUS) detected extraprostatic disease for prostate cancer (PCa) in patients receiving radical external beam radiation therapy (EBXRT).

A chart review of 187 patients treated with radical EBXRT for PCa was conducted. Twenty-eight (15.0%) patients had non palpable disease (T1), 112 (60.0%) patients had clinically palpable organ-confined disease (T2), 32 (17.0%) patients had extra-capsular disease (T3a, T3b), 14 (7.5%) patients had seminal vesicle involvement and 1 (0.5%) patient had bladder (T4a) involvement. The median radiation dose delivered to the prostate was 66 Gy (range 53-70 Gy) in 33 fractions (range 20-39 fractions). Median follow-up time for all patients was 6.5 years. Relapse of disease occurred in 57% of patients, with median time to relapse of 2.0 years.

All patients underwent TRUS assessment by one radiologist. TRUS extra-capsular (T3a or T3b) and seminal vesicle (T3c) involvement were found in 66 (36%) and 12 (6%) patients at diagnosis, respectively. Eleven (24%) of 46 patients with clinical T3 disease had disease downstaging with TRUS ultrasound (i.e. no extracapsular disease noted). Thirty-five (26%) of 136 patients with clinical T1-T2 disease had upstaging of disease by TRUS (extracapsular disease detected). For relapse rate, Gleason score (P = 0.033) and TRUS staging (P = 0.013) were found to be independent prognostic factors. For time to relapse, Gleason score (P = 0.031) and TRUS staging (P = 0.018) were also found to be independent prognostic factors.

We were able to demonstrate a difference in the prognosis between a TRUS stage T3 and a TRUS stage T1 or T2. The prognostic value of TRUS may depend on the definition of T3 disease, in terms of extension to the capsule. We recommend that TRUS T3 should only include tumors that spread through the capsule, in order to provide optimal discriminative power for this imaging modality. Using this definition, PCa staged by an experienced genitourinary radiologist to be a T3 on TRUS, but staged to be a T1-T2 on DRE, should be considered to be a T3 cancer.

Rodrigues, G, Yoon, F, Izawa, J, D'Souza, D, Lock, M, Downey, D, Transrectal Ultrasound Can Provide Prognostic Information for Patients Undergoing External Beam Radiation Therapy for Prostate Cancer.  Radiological Society of North America 2004 Scientific Assembly and Annual Meeting, November 28 - December 3, 2004 ,Chicago IL. http://archive.rsna.org/2004/4403799.html