Men diagnosed with the least dangerous, localized Prostate cancer have only a minimal risk of dying from the disease over the following 20 years, one of the largest and longest studies on the issue found on Tuesday.

“These results do not support aggressive treatment of localized, low-grade Prostate cancer,” by surgery or radiation, the report from the University of Connecticut Health Center said.

 

“Surveillance is really the best option for those patients,” added physician Peter Albertsen, who led the study.

His research, which began with 767 men and covered more than 20 years, also found that the death rate from Prostate cancer across the board appears to remain stable beyond 15 years after diagnosis.

That contradicts a recent Swedish study which reported a three-fold increase in prostate cancer mortality rates for men who survive more than 15 years after the disease is found.

Albertsen, whose findings appeared in this week’s Journal of the American Medical Association, said the conflict might be due to differences in how the disease was classified in each patient and how the causes of death were determined.

The men in the Connecticut study were between the ages of 55 and 74 when diagnosed with low stages of Prostate cancer as far back as 1971, meaning that the tumor had not progressed outside the gland. But they had many grades of tumors, from the least dangerous to the most virulent.

The men with low-grade or least dangerous tumors at diagnosis had a low risk of disease progression even after more than 20 years, with 7 percent dying of prostate cancer. Most died from other identifiable or unknown causes and 12 percent were still alive 20 to 33 years after diagnosis.

He said both his and the Swedish study do agree that men with tumors rated at the lower end of the Gleason rating system, widely used in the United States to define prostate tumors, rarely die from their disease; but men with tumors rated at the higher end of that scale die from it within five to 10 years of diagnosis, often despite aggressive interventions.

How to advise men with tumors in the middle of the scale

who otherwise have a life expectancy of greater than 15 years “poses the greatest challenge,” he said.