Another Prostate Cancer Screening Candidate Outperforms Standard PSA Testing

— Multiparametric Stockholm3 prevented even more unneeded biopsies without compromising level of sensitivity

by
Charles Bankhead,

Senior Editor, MedPage Today

January 28, 2024

SAN FRANCISCO– A multiparametric blood test for prostate cancer revealed possible to prevent over half of unneeded biopsies without compromising precision, a big potential research study revealed.

In a contrast versus the present PSA screening requirement of ≥ 4 ng/mL, the Stockholm3 biomarker, which integrates a PSA cutoff of 15 ng/mL with other proteins and genomic details, would have spared 56% of guys from biopsies for grade group (GG) 1 or benign illness. The basic PSA cutoff would have prevented 19% of unneeded biopsies, reducing to 10% with a cutoff of ≥ 3 ng/mL.

Level of sensitivity, uniqueness, and predictive worths with the multicomponent test either estimated or exceeded those attained with traditional PSA screening, reported Scott Eggener, MD, of the University of Chicago, at the Genitourinary Cancers Symposium

“Stockholm3 has the possible to decrease unneeded damages of prostate cancer screening,” stated Eggener. “Stockholm3 has appealing attributes in this varied accomplice, and [demonstrated] effective recruitment of a big associate of males from generally underrepresented minorities. The Stockholm3 needs to be offered in the early part of 2024.”

Throughout a conversation that followed the discussion, an audience following online asked how the Stockholm3 compared to other tests, such as the 4Kscore and the Prostate Health Index

“It’s a hectic area, the secondary biomarker area, and the concern constantly turns up is how they compare head to head,” stated Eggener. “They’re all based upon excellent science. All of them have great research studies revealing their worth. For a range of factors that you all most likely understand, it’s unusual for them to go head to head, so we actually do not understand.”

In action to another concern, Eggener kept in mind that the 16% rate of MRI usage in the research study was lower than may be anticipated in a population-based examination, most likely due to the fact that majority of the blood specimens were archival from a biobank.

“It would be fascinating to see if potential regular usage of MRI would alter the operating attributes,” he stated.

A last concern associated to detectives’ capability to hire a racially/ethnically varied population, as Asian, Black, and Hispanic clients represented a bulk of the blood specimens. Eggener stated detectives looked for taking part websites that have varied client populations.

Stockholm3: The Basics

The Stockholm3 includes proteins (overall and complimentary PSA plus 3 cancer-related proteins– GDF15, KLK2, and PSP94), polygenic danger utilizing 101 single-nucleotide polymorphisms, and client medical information. The test has a multiplex algorithm that utilizes the multiparametric information to anticipate the possibility of GG ≥ 2 prostate cancer. A threat rating ≥ 11 is thought about a sign of prostate cancer.

An preliminary research study carried out in Sweden revealed usage of the test minimized benign biopsies and medical diagnosis of medically irrelevant prostate cancers. In a subsequent research studyusage of the test decreased MRI treatments and recommendations for prostate biopsy. Racial and ethnic representation in prostate cancer trials is usually bad, Eggener kept in mind. Private investigators in the SEPTA research study looked for to deal with that problem by examining Stockholm3 efficiency metrics in a varied North American population, including 17 centers in the U.S. and Canada.

Qualified individuals were ages 45-75, had no recognized prostate cancer however a medical sign for prostate biopsy, and self-identified as Asian, Black/African American, Hispanic/Latino nonwhite, or white. All individuals had actually blood drawn prior to prostate biopsy.

The main endpoint was GG ≥ 2, and the essential secondary endpoints were GG 1 prostate cancer or benign illness. A main goal was to assess the relative level of sensitivity of Stockholm3 (PSA ≥ 15) and PSA ≥ 4 for finding GG ≥ 2. A 2nd goal was to compare the relative uniqueness of Stockholm3 and PSA ≥ 4 for preventing GG 1 cancer or benign illness.

SEPTA consisted of 912 males hired from the 17 getting involved websites plus 1,217 guys who had actually been biopsied and had actually biobanked blood. Research study individuals had an average age of 63 and a mean PSA of 6.1 ng/mL. A 4th of the clients had an irregular digital rectal test, 20% had a household history of prostate cancer, and 20% had a previous unfavorable biopsy. The mean Stockholm3 rating was 17, and 16% of the clients had actually gone through MRI-targeted biopsies.

Secret Findings

Detectives attained the ethnic variety they looked for, as 16% of clients were Asian, 24% were Black, 14% were Hispanic, and 46% were white. Biopsy outcomes revealed benign illness in 57% of cases, GG 1 prostate cancer in 14%, and GG ≥ 2 in 29%. Analysis of biopsy findings by ethnic culture revealed that Asian and Hispanic guys had more benign illness (69% and 60%, respectively) and Black guys had less benign medical diagnoses (49%). Detection of GG 1 was comparable throughout the groups (11-17%). Black males had more GG ≥ 2 (37%) and Asians had less (21%).

Biopsy outcomes revealed that a PSA ≥ 3 ng/mL identified 97% of GG ≥ 2, followed by PSA ≥ 4 (92%) and Stockholm3 (88%). Usage of Stockholm3 prevented practically 3 times as lots of unneeded biopsies as a PSA cutoff of ≥ 4 ng/mL and nearly 6 times more than a cutoff of ≥ 3.

As compared to PSA cutoffs of ≥ 3 or ≥ 4 ng/mL, the Stockholm3 test attained the following worths:

• Uniqueness: 56% vs 10% vs 19%, respectively
• Unfavorable predictive worth (NPV): 92% vs 91% vs 85%
• Level of sensitivity: 88% vs 97% vs 92%
• Favorable predictive worth (PPV): 44% vs 31% vs 31%

Reducing the Stockholm3 cutoff to ≥ 11 ng/mL caused somewhat much better NPV, level of sensitivity, and PPV, however at the cost of 18% more biopsies for low-risk and benign illness.