Prostagram magnetic resonance imaging in a screening population: Prostate Imaging-Reporting and Data System or Likert?

OBJECTIVE: To compare biopsy recommendation rates and accuracy of the Prostate Imaging-Reporting and Data System, version 2 (PI-RADSv2) with the Likert scale for detection of clinically significant and insignificant prostate cancer in men screened within the Imperial Prostate 1 Prostate Cancer Screening Trial Using Imaging (IP1-PROSTAGRAM). PATIENTS AND METHODS: Men aged 50-69 years were screened with Prostagram MRI. Scans were prospectively reported using both PI-RADSv2 (excluding dynamic contrast-enhanced sequence score) and 5-point Likert scores by expert uro-radiologists. Systematic and targeted transperineal biopsy was recommended if the scan was scored ≥ 3, based on either reporting system. The proportion of patients recommended for biopsy and detection rates for Grade Groups (GGs) 1 and ≥ 2 were compared. Receiver operating characteristic (ROC) analysis was performed to compare performance. RESULTS: A total of 406 men underwent Prostagram MRI. The median (interquartile range) age and prostate-specific antigen level were 57 (53-61) years and 0.91 (0.56-1.74) ng/mL, respectively. At MRI score ≥ 3, more patients were recommended for biopsy based on Likert criteria (94/406; 23%, 95% confidence interval [CI] 19.2%-27.6%) compared to PI-RADSv2 (72/406; 18%, 95% CI 14.2%-21.9%; P = 0.03). For MRI scores ≥ 4, PI-RADSv2 and Likert scales led to 43/406 (11%, 95% CI 7.9%-14.1%) and 35/406 (9%, 95% CI 6.2%-11.9%) men recommended for biopsy (P = 0.40). For GG ≥ 2 detection, PIRADSv2 and Likert detected 22% (95% CI 11.4%-30.8%, 14/72) and 16% (95% CI 9.5%-25.3%, 15/94), respectively (P = 0.56). For GG1 cancers detection these were 11% (95% CI 4.3%-19.6%, seven of 72) vs 11% (95% CI 4.7%-17.8%, nine of 94; P = 1.00). The accuracy of PI-RADSv2 and Likert scale was similar (area under the ROC curve 0.64 vs 0.65, P = 0.95). CONCLUSIONS: In reporting non-contrast-enhanced Prostagram MRI in a screening population, the PI-RADSv2 and Likert scoring systems were equally accurate; however, Likert scale use led to more men undergoing biopsy without a subsequent increase in significant cancer detection rates. To improve reporting of Prostagram MRI, either the PI-RADSv2 or a modified Likert scale or a standalone scoring system should be developed.

An Evaluation of Screening Pathways Using a Combination of Magnetic Resonance Imaging and Prostate-specific Antigen: Results from the IP1-PROSTAGRAM Study.

BACKGROUND: The use of prostate-specific antigen (PSA) testing to screen for prostate cancer has been fraught with under- and overdiagnosis. Short, noncontrast magnetic resonance imaging (MRI) might detect more grade group ≥2 cancers with similar rates of biopsy. OBJECTIVE: To evaluate strategies that combined PSA and MRI to select men based in the community for a prostate biopsy. DESIGN, SETTING, AND PARTICIPANTS: IP1-PROSTAGRAM was a prospective, population-based, paired cohort study of 408 men aged 50-69 yr conducted at seven UK primary care practice and two imaging centres (from October 10, 2018 to May 15, 2019). INTERVENTION: All participants underwent screening with a PSA test, MRI (T2-weighted and diffusion), and transrectal ultrasound (b-mode and elastography). If any test was screen positive, a systematic 12-core biopsy was performed. Additional image-fusion targeted biopsies were taken if the MRI or ultrasound was positive. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: We conducted an analysis, set out in the statistical plan a priori, comparing 13 different pathways including PSA-alone, MRI-alone, and a range of PSA thresholds and MRI scores. The performance of each pathway was evaluated focusing on the trade-offs between biopsy referral rates and detection of grade group ≥2 cancers. A targeted biopsy was performed only where the PROSTAGRAM MRI showed a lesion score of 3, 4, or 5. RESULTS AND LIMITATIONS: The standard PSA pathway (PSA ≥3 ng/ml + systematic biopsy) would lead to 10% of men being referred for a biopsy and a 1.0% detection rate of grade group ≥2 cancers. Pathways that relied on MRI alone set at a threshold score of 3 for a biopsy led to higher biopsy rates, but with benefit of high cancer detection rates. The pathway that combined an initial low PSA threshold (≥1.0 ng/ml) and MRI score ≥4 accurately identified a high rate of grade group ≥2 cancers (2.5%, 95% confidence interval 1.3-4.6) while recommending fewer patients for a biopsy (7.1%, 95% confidence interval 4.9-10.2). The results are pertinent to only one screening round, the impact of repeat screening rounds is not evaluated, and the required MRI capacity is currently lacking. CONCLUSIONS: Our results highlight the trade-off that exists between reducing excessive numbers of biopsies and maintaining grade group ≥2 cancer detection rates. A pathway that combines PSA ≥1 ng/ml and MRI score ≥4 maintains the detection of grade group ≥2 cancers while recommending fewer men for biopsies and would be the preferred strategy to evaluate in future studies at the first screening round. PATIENT SUMMARY: The IP1-PROSTAGRAM study shows that PROSTAGRAM magnetic resonance imaging in men with a prostate-specific antigen level of ≥1.0 ng/ml could be a promising pathway to evaluate in future screening trials.

Perceived patient burden and acceptability of MRI in comparison to PSA and ultrasound: results from the IP1-PROSTAGRAM study.

BACKGROUND: The IP1-PROSTAGRAM study showed that a short, non-contrast MRI detected more significant cancers with similar rates of biopsy compared to PSA. Herein, we compare the expected and perceived burden of PSA, MRI and ultrasound as screening tests. METHODS: IP1-PROSTAGRAM was a prospective, population-based, paired screening study of 408 men conducted at seven UK primary care practices and two imaging centres. The screening tests were serum PSA, non-contrast MRI and ultrasound. If any test was screen-positive, a prostate biopsy was performed. Participants completed an Expected Burden Questionnaire (EBQ) and Perceived Burden Questionnaire (PBQ) before and after each screening test. RESULTS: The overall level of burden for MRI and PSA was minimal. Few men reported high levels of anxiety, burden, embarrassment or pain following either MRI or PSA. Participants indicated an overall preference for MRI after completing all screening tests. Of 408 participants, 194 (47.5%) had no preference, 106 (26.0%) preferred MRI and 79 (19.4%) preferred PSA. This indicates that prior to screening, participants preferred MRI compared to PSA (+6.6%, 95% CI 4.4-8.4, p = 0.02) and after completing screening, the preference for MRI was higher (+21.1%, 95% CI 14.9-27.1, p < 0.001). The proportion of participants who strongly agreed with repeating the test was 50.5% for ultrasound, 65% for MRI and 68% for PSA. A larger proportion of participants found ultrasound anxiety-inducing, burdensome, embarrassing and painful compared to both MRI and PSA. CONCLUSIONS: Prostagram MRI and PSA are both acceptable as screening tests among men aged 50-69 years. Both tests were associated with minimal amounts of anxiety, burden, embarrassment and pain. The majority of participants preferred MRI over PSA and ultrasound. REGISTRATION: This study was registered on clinicaltrials.gov at https://clinicaltrials.gov/ct2/show/NCT03702439 .

Direct mail from primary care and targeted recruitment strategies achieved a representative uptake of prostate cancer screening.

BACKGROUND AND OBJECTIVES: Prostate cancer screening studies has previously not been able to reflect a diverse group of participants. We evaluated a range of recruitment strategies and their ability to recruit from the Black population and areas of deprivation. METHODS: IP1-PROSTAGRAM was a prospective, population-based, paired screening study of 408 participants conducted at seven UK primary care practices and two imaging centres. All participants underwent screening with a prostate specific antigen (PSA) test, magnetic resonance imaging (MRI), and transrectal ultrasound. A number of recruitment strategies were embedded including direct mail, media campaigns, and a targeted recruitment strategy to increase participation among harder-to-reach groups. RESULTS: A total of 1,316 expressions of interest were received (20th September 2018 to 15th May 2019). The direct mail strategy generated 317 expressions of interest from 1707 invitation letters. Overall 387 expressions of interest were received following the targeted strategy and 612 from media campaigns. The recruitment target was met 19 months ahead of the schedule. Of the 411 participants, ethnicity was White (38.0%), Black (32.4%), Asian (23.0%), and Other/Mixed (4.4%) ethnic groups. This higher recruitment of Black men was driven by the targeted recruitment strategy. A comparison of recruitment methods showed marked differences between ethnicities recruited (P < 0.001). The proportion of Black participants recruited by direct mail (8%) was similar to the prevalence of Black local population (9%) whereas, targeted recruitment was 88% (115) and media recruitment 1.7% (1). The Index of Multiple Deprivation (IMD) distribution was similar to the local population with marginal higher recruitment from more deprived areas; proportion increasing from 26% to 40% from least to most deprived IMD quintiles (Quintiles 4/5 vs. 1/2). Direct mail recruited a close-to-normal distribution for deprivation with targeted recruitment trending towards recruiting from most deprived areas. CONCLUSION: Direct mail and targeted strategies designed to engage a diverse population can achieve a representative uptake from Black participants and those from a lower socioeconomic group.

Population-Based Prostate Cancer Screening With Magnetic Resonance Imaging or Ultrasonography: The IP1-PROSTAGRAM Study.

IMPORTANCE: Screening for prostate cancer using prostate-specific antigen (PSA) testing can lead to problems of underdiagnosis and overdiagnosis. Short, noncontrast magnetic resonance imaging (MRI) or transrectal ultrasonography might overcome these limitations. OBJECTIVE: To compare the performance of PSA testing, MRI, and ultrasonography as screening tests for prostate cancer. DESIGN, SETTING, AND PARTICIPANTS: This prospective, population-based, blinded cohort study was conducted at 7 primary care practices and 2 imaging centers in the United Kingdom. Men 50 to 69 years of age were invited for prostate cancer screening from October 10, 2018, to May 15, 2019. INTERVENTIONS: All participants underwent screening with a PSA test, MRI (T2 weighted and diffusion), and ultrasonography (B-mode and shear wave elastography). The tests were independently interpreted without knowledge of other results. Both imaging tests were reported on a validated 5-point scale of suspicion. If any test result was positive, a systematic 12-core biopsy was performed. Additional image fusion-targeted biopsies were performed if the MRI or ultrasonography results were positive. MAIN OUTCOMES AND MEASURES: The main outcome was the proportion of men with positive MRI or ultrasonography (defined as a score of 3-5 or 4-5) or PSA test (defined as PSA ≥3 µg/L) results. Key secondary outcomes were the number of clinically significant and clinically insignificant cancers detected if each test was used exclusively. Clinically significant cancer was defined as any Gleason score of 3+4 or higher. RESULTS: A total of 2034 men were invited to participate; of 411 who attended screening, 408 consented to receive all screening tests. The proportion with positive MRI results (score, 3-5) was higher than the proportion with positive PSA test results (72 [17.7%; 95% CI, 14.3%-21.8%] vs 40 [9.9%; 95% CI, 7.3%-13.2%]; P < .001). The proportion with positive ultrasonography results (score, 3-5) was also higher than the proportion of those with positive PSA test results (96 [23.7%; 95% CI, 19.8%-28.1%]; P < .001). For an imaging threshold of score 4 to 5, the proportion with positive MRI results was similar to the proportion with positive PSA test results (43 [10.6%; 95% CI, 7.9%-14.0%]; P = .71), as was the proportion with positive ultrasonography results (52 [12.8%; 95% CI, 9.9%-16.5%]; P = .15). The PSA test (≥3 ng/mL) detected 7 clinically significant cancers, an MRI score of 3 to 5 detected 14 cancers, an MRI score of 4 to 5 detected 11 cancers, an ultrasonography score of 3 to 5 detected 9 cancer, and an ultrasonography score of 4 to 5 detected 4 cancers. Clinically insignificant cancers were diagnosed by PSA testing in 6 cases, by an MRI score of 3 to 5 in 7 cases, an MRI score of 4 to 5 in 5 cases, an ultrasonography score of 3 to 5 in 13 cases, and an ultrasonography score of 4 to 5 in 7 cases. CONCLUSIONS AND RELEVANCE: In this cohort study, when screening the general population for prostate cancer, MRI using a score of 4 or 5 to define a positive test result compared with PSA alone at 3 ng/mL or higher was associated with more men diagnosed with clinically significant cancer, without an increase in the number of men advised to undergo biopsy or overdiagnosed with clinically insignificant cancer. There was no evidence that ultrasonography would have better performance compared with PSA testing alone.