Third component of PCa score improves test accuracy

In addition to the two cell patterns that help determine the Gleason score, if a third, small area of highly aggressive cancer is seen on biopsy, it is associated with a worse prognosis for men with otherwise moderately aggressive disease, according to a study from Brigham and Women’s Hospital published in JAMA (2007; 298:1533-8).

“Currently, if a minor component of aggressive disease is found within a prostate cancer biopsy specimen, it is not uniformly included in the report of the Gleason score,” said Abhijit Patel, MD, PhD, the study’s lead author. “However, this research indicates that because this minor component of aggressive disease affects prognosis, it can alter treatment decisions, and should always be reported if present.”

Dr. Patel and colleagues explored the relationship between the presence or absence of a tertiary highly aggressive cell pattern of grade 5 and the time to PSA failure. For more than 4 years, they followed 2,370 men with localized or locally advanced prostate cancer who were treated with radical prostatectomy, radiation therapy, or radiation therapy with 6 months of androgen suppression therapy.

The team found that men with a Gleason score of 7 and a highly aggressive tertiary grade of 5 had a shorter time to disease recurrence compared with men with a Gleason score of 7 without a tertiary grade 5. Men with a Gleason score of 7 and tertiary grade 5 had an average of 5 years to recurrence compared with men who had a Gleason score of 7 without tertiary grade 5, who experienced recurrence within an average of 6.7 years. In addition, time to recurrence for men with a score of 7 and tertiary grade of 5 is comparable to men with a Gleason score between 8 and 10.

“There is no consensus about the optimal treatment for men with Gleason score 7 prostate cancer,” Dr. Patel said. “However, this study suggests that if the biopsy specimens of such men show a minor component of highly aggressive, grade 5 cancer, more than radiation or surgery alone will be needed to reduce recurrence rates in the majority of these men.”