Updated results of a Swedish screening study (GOTEBORG-2), reported in The New England Journal of Medicine by Hugosson et al, indicate that omitting biopsy among individuals with negative magnetic resonance imaging (MRI) results eliminated a high proportion of diagnoses of clinically insignificant prostate cancer.
Study Details
In the population-based trial that began in 2015, men in Gothenburg between the ages of 50 and 60 were invited to undergo prostate-specific antigen (PSA) screening. Men were randomly assigned to the systemic biopsy group (n = 6,578) or the MRI-targeted biopsy group (n = 6,575).
In the systemic biopsy group, men with a PSA level ≥ 3 ng/mL were invited to undergo MRI of the prostate followed by systemic biopsy irrespective of MRI results; targeted biopsy was performed if MRI revealed suspicious lesions. In the MRI-targeted therapy group, men with a PSA ≥ 3 ng/mL were invited to undergo prostate MRI, with MRI followed by targeted biopsy if suspicious lesions were observed. Men were invited for repeat screening 2, 4, or 8 years later, depending on their PSA level.
The primary outcome measure was detection of clinically insignificant prostate cancer, defined as International Society of Urological Pathology (ISUP) grade 1 disease.
Key Findings
After a median follow-up of 3.9 years, clinically insignificant disease had been detected in 185 of 6,575 men (2.8%) in the MRI-targeted biopsy group vs 298 of 6,578 men (4.5%) in the systemic biopsy group (relative risk [RR] = 0.43, 95% confidence interval [CI] = 0.32–0.57, P < .001). Relative risks at two subsequent screening rounds were 0.49 and 0.25.
Clinically significant cancer (ISUP grade ≥ 2) was observed in 117 men (1.8%) in the MRI-targeted biopsy group vs 139 (2.1%) in the systemic biopsy group (RR = 0.84, 95% CI = 0.66–1.07). Advanced or high-risk cancers (metastatic or ISUP grade 4 or 5) were detected in 15 men in the MRI-targeted biopsy group and 23 men in the systemic biopsy group (RR = 0.65, 95% CI = 0.34–1.24).
The investigators concluded: “In this trial, omitting biopsy in patients with negative MRI results eliminated more than half of diagnoses of clinically insignificant prostate cancer, and the associated risk of having incurable cancer diagnosed at screening or as interval cancer was very low.”
Jonas Hugosson, MD, PhD, of the Department of Urology, Sahlgrenska Academy, University of Gothenburg, is the corresponding author for The New England Journal of Medicine article.
Disclosure: The study was funded by the Karin and Christer Johansson’s Foundation and others. For full disclosures of the study authors, visit nejm.org.
