Prostate Cancer Deaths Can Occur Despite Normal Initial PSA
MILAN—One quarter of all men with an initially normal PSA level will be diagnosed with PCa within 16 years, and many will have incurable disease, researchers reported at the 28th annual European Association of Urology congress. The findings raise questions about whether the currently used screening algorithm has adequate sensitivity, according to researchers.
Maria Frånlund, MD, of Sahlgrenska University Hospital in Gothenburg, Sweden, and colleagues studied 2,246 men aged 50-64 years randomized to biennial PSA screening in the Gothenburg Randomized Screening Trial. The men had a total PSA level of 1.0-2.99 ng/mL during an initial screening round in 1995-1996. Men with a total PSA level of 3.0 or higher were recommended for prostate biopsy. The last date o follow-up was December 31, 2011.
After a median follow-up of nearly 16 years, PCa was diagnosed in 524 men (cumulative detection rate of 26.8%), Dr. Frånlund told attendees. The mean age at diagnosis was 65.8 years. Of these, 201 had low-risk disease (cumulative detect rate of 10.9%). The mean age of these men was 67.6 years. Incurable PCa developed in 61 men with a mean age of 70 years (cumulative detection rate of 3.6%). Fifteen of these patients died from PCa. Only one third of patients with incurable cancers had a low initial free-to-total (F/T) PSA ratio. Of 42 men who had a total PSA level of 1.00-1.99 in the first screening round, 12 later died from PCa.
In addition, Dr. Frånlund said the F/T PSA ratio at baseline seems to have limited value in predicting who will develop incurable PCa.
The researchers defined low-risk cancer as stage T1, not N1 or M1; a Gleason score of 6 or less; and a total PSA level below 10. They defined incurable PCa as either histologic or radiologic evidence of metastases, death from PCa, initiation of hormonal treatment or relapse after curative treatment.