Invasive methods unnecessary for PCa radiation therapy planning

Modern 3-D computed tomography is effective for locating the prostatic apex for radiation therapy treatment planning in prostate cancer patients because it eliminates the need for an invasive procedure and related side effects, according to a study in the International Journal of Radiation Oncology Biology Physics (2008; 71:51-7).

Researchers at the University of Texas Health Science Center, San Antonio, conducted the study to determine whether knowledge of the anatomic relationships of the prostatic base and the prostatic apex along with modern 3-D CT planning could be used as a substitute for retrograde urethrography. Fifteen patients underwent CT simulation both with and without bladder, urethral, and rectal contrast.

The prostatic base and apex were identified easily and consistently on both scans by taking a side view of the patient and drawing a line from the pubic bone straight down to the floor of the pelvis. The process was repeated and confirmed in another 57 patients, leading researchers to determine that it is not necessary to subject a patient to a urinary catheter for contrast delivery.

“By using CT scans to find the prostatic apex, patients are happier and we have the same results,” said co-author Gregory Swanson, MD. “I stopped doing contrast in 1995 or 1996 when I realized that I knew where the prostate was without using invasive methods. I have been successful in using CT since then.”