Prostate Cancers in the Prostate-specific Antigen Interval of 1.8–3 ng/ml: Results from the Göteborg-2 Prostate Cancer Screening Trial

Background Magnetic resonance imaging (MRI) and targeted biopsies reduce overdiagnosis of prostate cancer (PC). It is uncertain how this strategy performs for low prostate-specific antigen (PSA) levels. Objective To investigate the Prostate Imaging Reporting and Data System (PI-RADS) distribution, frequency, and characteristics of screen-detected PC with PSA of 1.8–<3 ng/ml and 3–<10 ng/ml. Design, setting, and participants In the population-based Göteborg-2 screening study, 17974 men choose to participate by having a PSA test (2015–2020). One-third of the participants (n = 6006) were randomized to arm 3, men with a PSA value of ≥1.8 ng/ml were recommended for MRI. Men with positive MRI (PI-RADS 3–5) had four targeted biopsies from each MRI-visible lesion. Outcome measurements and statistical analysis Clinically significant PC was defined as Gleason score ≥3 + 4. Results and limitations A total of 6006 men were included. The median age was 55.9 yr (interquartile range [IQR] 52.6–59.6). Of them, 4929 (82%) had PSA of <1.8 ng/ml, 670 (11%) had PSA of 1.8–<3 ng/ml (low-PSA group, median PSA 2.1 ng/ml [IQR 1.9–2.5]), and 377 (6.3%) had PSA of 3–<10 ng/ml (high-PSA group, median PSA 3.9 ng/ml [IQR 3.3–5.0]). PI-RADS scores of 3, 4, and 5 were observed in 7.8%, 15%, and 1.0% of men in the low-PSA group, and in 6.9%, 17%, and 5.3% of men in the high-PSA group, respectively. PC was found in 64 men (41%, 95% confidence interval [CI] 0.33–0.49) with positive MRI findings in the low-PSA group, of whom 33 (21%) had Gleason 6 (insignificant PC) and 31 (20%) had Gleason ≥7 (significant PC). In the high-PSA group, PC was detected in 61 men (56%, 95% CI 0.46–0.66), of whom 26 (24%) had Gleason 6 (insignificant PC) and 35 (32%) had Gleason ≥7 (significant PC). Limitations include results from only a single screening round. Conclusions A non-negligible number of men with PSA 1.8–3 ng/ml have clinically significant PC. Whether a delay in the diagnosis of these tumors until they reached PSA ≥3 ng/ml would impair their chance of cure remains to be evaluated. Patient summary We studied screening using prostate-specific antigen (PSA) and magnetic resonance imaging in men with PSA 1.8–3 ng/ml. We found a non-negligible number of potentially harmful prostate cancers in these men.