Modern PSA screening reduces the risk of cancer returning

This study examined the outcome of patients treated with radical prostatectomy (surgical removal of the prostate) whose cancer had spread to the seminal vesicles (glands positioned below the bladder; stage T3b).

The risk of dying from prostate cancer is low because the cancer usually grows very slowly. The risk increases if the cancer has begun to spread through the prostate and into nearby areas such as the seminal vesicles.

Prostate-specific antigen (PSA) is a protein produced by the prostate; its levels are elevated in patients with prostate cancer. Since 1987 PSA screening has been used to follow the progression of the cancer in patients. If the PSA levels increase after surgery it is known as biochemical recurrence. As a result of PSA screening the number of patients with cancer that has spread to the seminal vesicles has decreased to less than 10%. However, the outcome of these patients since PSA screening was introduced remains unclear.

This study included 229 men who underwent surgery for prostate cancer that had spread to the seminal vesicles. The patients were divided into two groups: 113 patients in group 1 (early PSA screening era; 1987-1997) and 116 patients in group 2 (modern PSA screening era; 1998-2008). The microscopic appearance of the patients’ cancer was graded using the Gleason grade (the lower the grade the less likely it is the tumor will spread).

Patients in the modern PSA screening era were diagnosed at a younger age, had lower PSA levels, had lower cancer grade, used less radiation therapy and used more hormone therapy.

The risk of the cancer returning decreased by 85% in patient from the modern PSA screening group compared to early PSA screening. The risk of biochemical recurrence decreased by 51% in patients from the modern PSA screening group.

Overall, the Gleason grade was the biggest statistical predictor of cancer returning and patient survival. A Gleason grade of 8 or more increased the risk of death by 2 fold compared to a score of 6 or less. It also increased the risk of the cancer returning by 5.1 fold and of biochemical recurrence by 3.5 fold. 

The authors concluded that prostate surgery offered long-term cancer control for patients with cancer cells in the seminal vesicles. They also concluded that the Gleason grade was the best predictor of overall survival and of cancer returning for these patients.

This was a retrospective study which may limit how generalizable the results are.