The incidence of advanced prostate cancer in California rose markedly in the decade since doctors stopped routinely screening all men for the disease, according to a new study by UC San Francisco.

After declining for many years, the death rate from the disease also plateaued in most regions across the state.

The findings reinforce the need for screening that can identify potentially fatal tumors without raising false alarms about ones that pose no threat to the patient.

The study appears Jan. 27 in JAMA Network Open.

“This overall rising trend is alarming and has occurred across age groups, regions of California, races and ethnicities,” said lead author Erin L. Van Blarigan, ScD, UCSF associate professor of Epidemiology & Biostatistics and Urology.

“Our data point to how urgent this problem is,” said Van Blarigan, who is also with the UCSF Helen Diller Family Comprehensive Cancer Center. “Figuring out the best way to screen for prostate cancer continues to be a challenge for researchers and doctors. Without screening, the number of men diagnosed with advanced prostate cancer — when treatments are less effective — increases fast.”

The challenge of screening for prostate cancer

Among men in the U.S., prostate cancer is the most common cancer and second-leading cause of cancer deaths. While some tumors are aggressive and can lead to death, the majority are low-grade and never spread.

The most frequently used screening tool is PSA testing (prostate specific antigen), which does not differentiate between aggressive or non-aggressive tumors, leading many men to be diagnosed with cancers that would not hurt them in the long run.

On the other hand, if screening isn’t done, timely diagnosis of more advanced cancers can be missed — those cancers might have been successfully treated if found early.

After years of screening all men for prostate cancer, the U.S. Preventative Services Task Force stopped recommending it in 2012. They hoped to prevent unnecessary and potentially harmful interventions, like surgery, for men whose disease was not serious.

In 2018, they began recommending that men between the ages of 55 and 69 discuss possible benefits and harms of screening with their doctors. But, as the authors note, this may not always be happening.

Prostate cancer mortality stops falling

UCSF researchers analyzed data involving nearly 388,000 men with prostate cancer in California between 2004 and 2021. Almost 28,000 (7.2%) had advanced disease, which has a five-year survival rate of just 37%. During the study timeframe, there were 58,754 deaths from prostate cancer.

Investigators looked at 10 regions spanning the state to see if rates in certain areas were increasing faster or slower.

They found that serious disease, which had been stable or dropping until 2010, grew 6.7% a year from 2011 to 2021. By contrast, national rates grew by 4.5% a year from 2011 to 2019. The lowest annual increase was in the Southern San Joaquin Valley (2.3%), the highest was in the Central Coast (9.1%).

Prostate cancer mortality dropped by 2.6% a year between 2004 and 2012; but after that, it plateaued in 7 out of 10 regions in the state. Mortality was highest in the Inland Empire followed by San Diego-Imperial and North Coast. It was lowest in the San Francisco Bay Area.

“It’s important to continue monitoring prostate cancer trends both in California and nationally as we learn more about the impact of screening guidelines on different populations,” said senior author Scarlett L. Gomez, PhD, MPH, UCSF professor in the Department of Epidemiology & Biostatistics.