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A clinician points to a model of the human prostate gland to a person out of frame but with their palms crossed on the desk beside a keyboard.
Some prostate cancers are clinically insignificant because they do not become symptomatic even when left untreated.
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Multistep Screening Detects Prostate Cancer Effectively

The new screening method in trials includes two blood tests and an MRI scan of the prostate, if necessary

Tampere University

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Published:Apr 10, 2024
|2 min read
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The ProScreen trial coordinated by Tampere University, Finland, and the University of Helsinki investigated the performance of a three-step prostate cancer screening method. The aim was to analyze whether the new method would efficiently reduce mortality while decreasing the major adverse effect of previous screening methods: overdiagnosing insignificant prostate cancers.

Some prostate cancers are clinically insignificant because they do not become symptomatic even when left untreated: Such cancers are frequently detected during autopsy. Thus, treating cancer with a good prognosis can still harm the patients’ quality of life.

The screening method used in the ProScreen study includes two blood tests and, if necessary, an MRI scan of the prostate. The previously studied screening method is based only on one blood test, the prostate-specific antigen test (PSA).

In the ProScreen study, both blood tests were positive in 7 percent of the participants and they were invited to an MRI of the prostate. In about half of these men, a suspicious area was detected by MRI and a prostate biopsy was taken.

Cancer was eventually found in about 2 percent of the participants. Clinically insignificant cancers were diagnosed in 4 in 1,000 men. “We have previously demonstrated that PSA screening can decrease prostate cancer mortality to some extent. However, PSA screening produces so many unnecessary cancer diagnoses that the harms outweigh the benefits. The new results show that the new three-step method produces fewer insignificant cancer diagnoses than PSA screening,” says professor of epidemiology Anssi Auvinen, MD, PhD, from Tampere University.

Overdiagnosing clinically insignificant cancers

Some prostate cancers are clinically insignificant, i.e., they will not progress to the symptomatic stage or cause any harm. The co-lead investigator of the project, professor of urology Antti Rannikko, MD, PhD, from the University of Helsinki, points out that detecting such latent cancers does not bring any benefits and should not even be diagnosed. 

“The vast majority of tumors found with the previous PSA screenings are low-risk cases that are likely to represent overdiagnosis. Most of them do not progress to the symptomatic stage even when left untreated. If a prostate cancer with a good prognosis is diagnosed, the primary treatment is always active surveillance,” Rannikko says.

Local prostate cancer is usually treated surgically or with radiation therapy. The common side effects of treatment include erectile dysfunction, urinary incontinence, and bowel symptoms.

Reducing cancer-associated mortality

The study included over 60,000 men aged 50–63 years, randomly allocated for either the three-step screening or a control group without intervention.

The study population will expand to include the neighboring municipalities of Tampere and Helsinki in Finland. Men who have already participated will be invited to a new screening after two to six years based on the outcomes of their first screening.

Population-level screening programs haven’t been launched in Finland or most other European countries but there is an ongoing health policy debate. According to the researchers, only preliminary evidence of the benefits of the new screening model is available so far. However, the results seem to indicate that major benefits could potentially be achieved in the future. The benefits can only be estimated after a 10-year follow-up when the effects on prostate cancer mortality have been analyzed.

“The aim of cancer screening is always to reduce mortality. The main criterion for decisions on cancer screening should always be the reduction of mortality,” Auvinen says. “The ProScreen study, due to its large size and randomized design, can produce the research evidence needed to justify screening decisions,” he adds.

- This press release was originally published on the Tampere University website