{"product_id":"prostate-cancer-screening-in-young-men-why-combining-two-biopsy-methods-improves-detection-results-from-the-probase-trial","title":"Prostate Cancer Screening in Young Men: Why Combining Two Biopsy Methods Improves Detection — Results from the PROBASE Trial","description":"\u003cp\u003eProstate cancer screening in younger men (ages 45–54) is challenging because standard MRI-targeted biopsies may miss clinically significant cancers. This study from the German PROBASE trial followed 525 men with elevated PSA levels and found that using only two targeted biopsy cores per MRI lesion missed 33% of clinically significant prostate cancers, while adding systematic (12-core) biopsies reduced missed cases to 16%. The researchers conclude that additional systematic cores—or more thorough sampling around suspicious MRI areas—are valuable complements to targeted biopsy in this age group, particularly in younger men with smaller prostates.\u003c\/p\u003e\n\n\u003ch1\u003eProstate Cancer Screening in Young Men: Why Combining Two Biopsy Methods Improves Detection — Results from the PROBASE Trial\u003c\/h1\u003e\n\n\u003ch2\u003eTable of Contents\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"#ddn-key-points\"\u003eKey Points\u003c\/a\u003e\u003c\/li\u003e\n\n  \u003cli\u003e\u003ca href=\"#background\"\u003eBackground: The Challenge of Prostate Cancer Screening in Young Men\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"#methods\"\u003eStudy Methods: How the Research Was Conducted\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"#key-findings\"\u003eKey Findings: Cancer Detection Rates by Biopsy Method\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"#discrepancies\"\u003eDetailed Breakdown: When Systematic and Targeted Biopsies Disagreed\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"#why-missed\"\u003eWhy Cancers Were Missed on Targeted Biopsy\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"#clinical-implications\"\u003eClinical Implications: What This Means for Patients\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"#limitations\"\u003eStudy Limitations: What This Study Could Not Prove\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"#recommendations\"\u003eRecommendations for Patients and Doctors\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"#ddn-faq\"\u003eFrequently Asked Questions\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"#source\"\u003eSource Information\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003c!-- ddn:keypoints:start --\u003e\n\u003ch2 id=\"ddn-key-points\"\u003eKey Points\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eIn 525 men aged 44–54, targeted biopsy alone missed 33% of clinically significant prostate cancers, versus 16% for systematic biopsy.\u003c\/li\u003e\n\u003cli\u003eSystematic biopsy detected 26% of significant cancers that targeted biopsy completely missed, showing the two methods are complementary.\u003c\/li\u003e\n\u003cli\u003eHalf of high-risk cancers were upgraded based on systematic biopsy cores, so combining methods improves accurate grading.\u003c\/li\u003e\n\u003cli\u003eMRI-visible lesions were often small (10 mm), and poor image quality contributed to out-of-field misses.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- ddn:keypoints:end --\u003e\n\n\n\u003ch2 id=\"background\"\u003eBackground: The Challenge of Prostate Cancer Screening in Young Men\u003c\/h2\u003e\n\n\u003cp\u003eProstate cancer is the most common cancer in men, and finding it early can save lives. For decades, the standard approach to screening has been a blood test for prostate-specific antigen (PSA), followed by a systematic biopsy if the PSA level is elevated. In this approach, doctors take tissue samples (cores) from throughout the prostate gland—typically 12 cores—using ultrasound guidance.\u003c\/p\u003e\n\n\u003cp\u003eWhile this strategy has been shown to reduce prostate cancer–related deaths, it comes with a major downside: a high rate of \u003cstrong\u003eoverdiagnosis\u003c\/strong\u003e—finding slow-growing, low-risk cancers that would never have caused harm. This leads to numerous unnecessary biopsies and can cause anxiety, pain, and complications.\u003c\/p\u003e\n\n\u003cp\u003eIn recent years, \u003cstrong\u003emultiparametric magnetic resonance imaging (mpMRI)\u003c\/strong\u003e has emerged as an essential tool in the prostate cancer diagnostic pathway. Current guidelines recommend MRI before biopsy for men with elevated PSA. If the MRI shows a suspicious area (scored using the \u003cstrong\u003eProstate Imaging-Reporting and Data System, or PI-RADS\u003c\/strong\u003e, on a scale of 1 to 5), doctors can perform a \u003cstrong\u003etargeted biopsy (TBx)\u003c\/strong\u003e, directing needles specifically at the suspicious lesion, often using software that fuses the MRI images with real-time ultrasound images.\u003c\/p\u003e\n\n\u003cp\u003eHowever, the role of MRI-guided biopsy in screening younger men—particularly those aged 45 to 55—remains unclear. MRI reading in young men is challenging because the prostate is smaller and MRI results depend heavily on the reader's experience. This study, from the large German \u003cstrong\u003ePROBASE trial\u003c\/strong\u003e, was designed to answer a critical question: does adding systematic biopsy to targeted biopsy meaningfully improve the detection of \u003cstrong\u003eclinically significant prostate cancer (csPC)\u003c\/strong\u003e—cancers that are aggressive enough to potentially threaten life?\u003c\/p\u003e\n\n\u003cp\u003eThe research team had previously reported initial results comparing the two biopsy methods and received an accompanying editorial raising concerns about the relatively low detection rate with targeted biopsy alone. This paper provides a more detailed analysis to explain those differences and to investigate potential reasons why targeted biopsy might miss aggressive cancers in younger men.\u003c\/p\u003e\n\n\u003ch2 id=\"methods\"\u003eStudy Methods: How the Research Was Conducted\u003c\/h2\u003e\n\n\u003ch3\u003eTrial Design and Participants\u003c\/h3\u003e\n\n\u003cp\u003eThe PROBASE trial is a large, multicenter, prospective screening study conducted in Germany. Between February 2014 and December 2019, \u003cstrong\u003e46,495 eligible participants aged 45 years\u003c\/strong\u003e were recruited from the general population. They were randomized in a 1:1 ratio into two screening groups:\u003c\/p\u003e\n\u003col\u003e\n  \u003cli\u003e\n\u003cstrong\u003eImmediate screening arm:\u003c\/strong\u003e PSA testing at age 45 years\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eDeferred screening arm:\u003c\/strong\u003e First PSA testing delayed until age 50 years\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003cp\u003eParticipants with a confirmed elevated PSA level of \u003cstrong\u003e3.0 ng\/ml or higher\u003c\/strong\u003e were recommended to undergo MRI followed by biopsy. From the overall cohort, \u003cstrong\u003e722 men (1.6%)\u003c\/strong\u003e had undergone biopsy by August 2023. After excluding repeat biopsies, cases with external MRI or external biopsy performed outside the study centers (67 men, primarily because the targeted cores and reports could not be traced), the final study cohort consisted of \u003cstrong\u003e525 participants\u003c\/strong\u003e—all of whom had a primary mpMRI and combined targeted plus systematic biopsy at one of four study sites.\u003c\/p\u003e\n\n\u003cp\u003eThe final cohort had a \u003cstrong\u003emedian age of 50 years (range 44–54)\u003c\/strong\u003e. Baseline characteristics included:\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003eMedian PSA level: \u003cstrong\u003e3.98 ng\/ml\u003c\/strong\u003e (interquartile range [IQR] 3.45–5.09)\u003c\/li\u003e\n  \u003cli\u003eMedian prostate volume: \u003cstrong\u003e36 ml\u003c\/strong\u003e (IQR 28–46)\u003c\/li\u003e\n  \u003cli\u003eMedian PSA density (PSAD, the PSA level divided by prostate volume): \u003cstrong\u003e0.12 ng\/ml²\u003c\/strong\u003e (IQR 0.09–0.16)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eImportantly, \u003cstrong\u003ePSAD was significantly higher and prostate volume was significantly lower\u003c\/strong\u003e in the group with a positive biopsy compared to the group with a negative biopsy (\u003cem\u003ep\u003c\/em\u003e \u0026lt; 0.001). This means that men who were found to have cancer tended to have smaller prostates and higher PSA density.\u003c\/p\u003e\n\n\u003ch3\u003eMRI Performance\u003c\/h3\u003e\n\n\u003cp\u003eAll MRI scans were performed on \u003cstrong\u003e3-Tesla (3T) MRI scanners\u003c\/strong\u003e, the highest-strength scanners commonly used in clinical practice. The imaging protocol followed international recommendations and included:\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003eT2-weighted turbo spin-echo sequences in three planes\u003c\/li\u003e\n  \u003cli\u003eDiffusion-weighted imaging (DWI) with b values of 0\/50, 500, and 1000, plus a calculated high b-value of 1400 s\/mm²\u003c\/li\u003e\n  \u003cli\u003eDynamic contrast enhancement after intravenous administration of a gadolinium-based contrast agent at a dose of \u003cstrong\u003e0.1 mmol per kilogram of body weight\u003c\/strong\u003e, with a temporal resolution of 5–9 seconds\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eMRI scans were read by board-certified radiologists at each of the four study locations. The likelihood of clinically significant cancer was rated using \u003cstrong\u003ePI-RADS version 2.1\u003c\/strong\u003e. Of note, there was \u003cstrong\u003eno centralized review of MRI scans before biopsy\u003c\/strong\u003e—meaning biopsy decisions were based on each local radiologist's interpretation. This is important context for understanding some of the findings.\u003c\/p\u003e\n\n\u003ch3\u003eBiopsy Procedure\u003c\/h3\u003e\n\n\u003cp\u003eAll biopsies were performed by trained urologists using \u003cstrong\u003esoftware-guided MRI\/ultrasound fusion biopsy\u003c\/strong\u003e. This technology combines pre-biopsy MRI images with real-time transrectal ultrasound images to guide the biopsy needle to suspicious areas. Commercially available systems included Koelis, BiopSee, and UroNAV.\u003c\/p\u003e\n\n\u003cp\u003eThe biopsy procedure consisted of two components:\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eTargeted biopsy (TBx):\u003c\/strong\u003e A maximum of four MRI lesions (according to PI-RADS) were defined for targeting, with a \u003cstrong\u003emedian of two cores taken per target lesion\u003c\/strong\u003e.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSystematic biopsy (SBx):\u003c\/strong\u003e A scheme based on prostate size was used, consisting in most cases of \u003cstrong\u003e12 independent systematic cores\u003c\/strong\u003e taken from throughout the prostate gland.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eBiopsies were performed either \u003cstrong\u003etransrectally\u003c\/strong\u003e (through the rectum) or \u003cstrong\u003etransperineally\u003c\/strong\u003e (through the skin between the scrotum and anus), depending on the approach chosen at each center.\u003c\/p\u003e\n\n\u003cp\u003eAll tissue samples were analyzed locally, and then \u003cstrong\u003ecentrally reviewed by an experienced genitourinary pathologist with 20 years of experience\u003c\/strong\u003e. Cancers were classified using the \u003cstrong\u003eInternational Society of Urological Pathology (ISUP) Grade Group (GG) system\u003c\/strong\u003e, which ranges from GG 1 (lowest risk) to GG 5 (highest risk). A cancer was defined as \u003cstrong\u003eclinically significant (csPC) if it was ISUP Grade Group 2 or higher\u003c\/strong\u003e.\u003c\/p\u003e\n\n\u003ch3\u003eDefining \"Missed\" Cancers\u003c\/h3\u003e\n\n\u003cp\u003eThe researchers used specific definitions to analyze discrepancies between the two biopsy methods:\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFusion failure:\u003c\/strong\u003e A case where systematic biopsy found cancer in the same area that MRI had flagged as suspicious, but the targeted biopsy of that area was negative.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eIn-field positive result:\u003c\/strong\u003e When MRI revealed a suspicious lesion (PI-RADS 3–5) and the systematic biopsy core was positive in that exact same area.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePenumbra positive result:\u003c\/strong\u003e When the positive systematic biopsy core was located next to the suspicious MRI area (in any spatial direction).\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eOut-of-field result:\u003c\/strong\u003e When positive systematic biopsy cores were found entirely outside the MRI target area.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eStatistical comparisons of detection rates between the two biopsy approaches were performed using \u003cstrong\u003eMcNemar tests\u003c\/strong\u003e with rate differences and 95% confidence intervals, as described by Tango. Statistical significance was set at \u003cem\u003ep\u003c\/em\u003e \u0026lt; 0.05.\u003c\/p\u003e\n\n\u003ch2 id=\"key-findings\"\u003eKey Findings: Cancer Detection Rates by Biopsy Method\u003c\/h2\u003e\n\n\u003ch3\u003eOverall Cancer Detection\u003c\/h3\u003e\n\n\u003cp\u003eAmong the 525 men in the study, \u003cstrong\u003eprostate cancer was detected in 209 men (39% of the cohort)\u003c\/strong\u003e. The distribution of cancers by Grade Group was:\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003eGG 1 (low-risk): 61 patients (29%)\u003c\/li\u003e\n  \u003cli\u003eGG 2: 106 patients (51%)\u003c\/li\u003e\n  \u003cli\u003eGG 3: 26 patients (12%)\u003c\/li\u003e\n  \u003cli\u003eGG 4: 11 patients (5.3%)\u003c\/li\u003e\n  \u003cli\u003eGG 5: 5 patients (2.4%)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eA substantial majority of cancers were clinically significant: \u003cstrong\u003e148 of 209 cases (71%) were GG 2 or higher\u003c\/strong\u003e.\u003c\/p\u003e\n\n\u003cp\u003eThe number of suspicious lesions seen on MRI varied among patients: one suspicious area was seen in 216 cases, two areas in 198 cases, three areas in 96 cases, and four areas in 15 cases.\u003c\/p\u003e\n\n\u003ch3\u003eDetection Rates: Systematic vs. Targeted Biopsy\u003c\/h3\u003e\n\n\u003cp\u003eThe two biopsy methods performed very differently in their ability to catch clinically significant cancers:\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003e\u003cstrong\u003eSystematic biopsy detected clinically significant prostate cancer in 139 of 148 cases (94%)\u003c\/strong\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003cstrong\u003eTargeted biopsy detected clinically significant prostate cancer in 109 of 148 cases (74%)\u003c\/strong\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eIn other words, \u003cstrong\u003eSBx missed 24 of 148 csPC cases (16%)\u003c\/strong\u003e, while \u003cstrong\u003eTBx missed 49 of 148 csPC cases (33%)\u003c\/strong\u003e—more than double the miss rate. The risk of missing csPC on targeted biopsy did not significantly differ by biopsy route (transrectal versus transperineal).\u003c\/p\u003e\n\n\u003cp\u003eEven more striking was the breakdown of who detected what:\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003e39 clinically significant cancers (26% of all csPC cases) were found ONLY on systematic biopsy\u003c\/strong\u003e — targeted biopsy was negative in these men.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003e9 clinically significant cancers (6%) were diagnosed ONLY via targeted biopsy\u003c\/strong\u003e — systematic biopsy was negative in these men.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eThis 26% unique detection rate for systematic biopsy represents a substantial proportion of aggressive cancers that would have been completely missed if only targeted biopsy had been used.\u003c\/p\u003e\n\n\u003ch3\u003eLow-Risk Prostate Cancer Detection\u003c\/h3\u003e\n\n\u003cp\u003eFor low-risk (GG 1) prostate cancer, systematic biopsy found more cases than targeted biopsy: \u003cstrong\u003e51 cases on SBx versus 26 cases on TBx\u003c\/strong\u003e—25 more low-risk cancers detected by the systematic approach. This highlights the trade-off in prostate cancer diagnosis: while systematic biopsy catches more clinically significant cancers, it also catches more low-risk cancers that might never need treatment.\u003c\/p\u003e\n\n\u003ch3\u003eDetection of High-Risk Cancers (GG 3–5)\u003c\/h3\u003e\n\n\u003cp\u003eOne-fifth of all prostate cancer cases (\u003cstrong\u003e42 of 209 cases, 20%\u003c\/strong\u003e) were classified as high-risk, meaning they had a Grade Group of 3, 4, or 5. These are the cancers most likely to threaten a man's life, so detecting them reliably is critical.\u003c\/p\u003e\n\n\u003cp\u003eOf these high-risk cancers:\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003e7 cases (16.7%) were detected exclusively via targeted biopsy\u003c\/strong\u003e — including 4 GG 3 cases, 2 GG 4 cases, and 1 GG 5 case.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003e22 cases (52%) were upgraded to high-risk based on systematic biopsy cores\u003c\/strong\u003e — including 17 GG 3, 4 GG 4, and 1 GG 5 cases.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eThis means that in more than half of the high-risk cancers, the systematic biopsy was responsible for revealing the true aggressive nature of the disease.\u003c\/p\u003e\n\n\u003ch2 id=\"discrepancies\"\u003eDetailed Breakdown: When Systematic and Targeted Biopsies Disagreed\u003c\/h2\u003e\n\n\u003cp\u003eTo fully understand how the two biopsy methods complement each other, the researchers analyzed 209 total cancer cases and compared the Grade Group results from each method.\u003c\/p\u003e\n\n\u003ch3\u003eAgreement Between Methods\u003c\/h3\u003e\n\n\u003cp\u003eIn \u003cstrong\u003e74 of 209 cases (35%)\u003c\/strong\u003e, both biopsy methods returned the same Grade Group:\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003e16 cases were GG 1 on both\u003c\/li\u003e\n  \u003cli\u003e48 cases were GG 2 on both\u003c\/li\u003e\n  \u003cli\u003e5 cases were GG 3 on both\u003c\/li\u003e\n  \u003cli\u003e3 cases were GG 4 on both\u003c\/li\u003e\n  \u003cli\u003e2 cases were GG 5 on both\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhen Systematic Biopsy Found Higher-Grade Cancer (94 cases)\u003c\/h3\u003e\n\n\u003cp\u003eIn \u003cstrong\u003e94 cases, systematic biopsy detected a higher Grade Group than targeted biopsy\u003c\/strong\u003e. Breaking this down:\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eIn 74 cases, TBx was completely negative (no cancer found): these included 35 GG 1 cases, 28 GG 2 cases, 9 GG 3 cases, 1 GG 4 case, and 1 GG 5 case found on SBx.\u003c\/li\u003e\n  \u003cli\u003eIn 10 cases, TBx found GG 1 while SBx found GG 2 (9 cases) or GG 3 (1 case).\u003c\/li\u003e\n  \u003cli\u003eIn 10 cases, TBx found GG 2 while SBx found GG 3 (7 cases) or GG 4 (3 cases).\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhen Targeted Biopsy Found Higher-Grade Cancer (41 cases)\u003c\/h3\u003e\n\n\u003cp\u003eIn \u003cstrong\u003e41 cases, targeted biopsy detected a higher Grade Group than systematic biopsy\u003c\/strong\u003e:\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eIn 19 cases, SBx was completely negative: these included 10 GG 1 cases, 6 GG 2 cases, 1 GG 3 case, 1 GG 4 case, and 1 GG 5 case found on TBx.\u003c\/li\u003e\n  \u003cli\u003eIn 15 cases, SBx found GG 1 while TBx found GG 2.\u003c\/li\u003e\n  \u003cli\u003eIn 4 cases, SBx found GG 2 while TBx found GG 3 (3 cases) or GG 4 (1 case).\u003c\/li\u003e\n  \u003cli\u003eIn 3 cases, SBx found GG 3 while TBx found GG 4 (2 cases) or GG 5 (1 case).\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eThe researchers also examined a subset of 49 cases where systematic biopsy upgraded the cancer to clinically significant status. In \u003cstrong\u003e38 of these 49 cases (78%), more than one suspicious area or lesion was identified on MRI\u003c\/strong\u003e—suggesting that when multiple lesions are present, systematic biopsy becomes even more valuable for catching all aggressive areas.\u003c\/p\u003e\n\n\u003ch2 id=\"why-missed\"\u003eWhy Cancers Were Missed on Targeted Biopsy\u003c\/h2\u003e\n\n\u003cp\u003eThe central question of this study was: \u003cem\u003ewhy does targeted biopsy miss so many clinically significant cancers when MRI has already identified suspicious areas?\u003c\/em\u003e The researchers found two main explanations.\u003c\/p\u003e\n\n\u003ch3\u003eReason 1: Targeting Inaccuracy (In-Field and Penumbra Misses)\u003c\/h3\u003e\n\n\u003cp\u003eIn \u003cstrong\u003e57 of 89 cases (64%)\u003c\/strong\u003e where systematic biopsy detected a higher Grade Group than targeted biopsy (including GG 1 cases), the positive systematic biopsy core was located within the same area identified on pre-biopsy MRI, or directly adjacent to it (penumbra). The median maximum lesion diameter on MRI for these cases was \u003cstrong\u003e10 mm (IQR 8–13 mm)\u003c\/strong\u003e—very small lesions that are inherently difficult to hit accurately with a biopsy needle.\u003c\/p\u003e\n\n\u003cp\u003eThe distribution of these \"in-field\" and \"penumbra\" positive cores was:\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eIn-field (35 cases):\u003c\/strong\u003e 9 GG 1, 18 GG 2, 8 GG 3\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePenumbra (22 cases):\u003c\/strong\u003e 7 GG 1, 7 GG 2, 8 GG 3\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eThis indicates that \u003cstrong\u003eMRI correctly identified the cancer-bearing area, but the targeted biopsy needle did not hit the lesion precisely\u003c\/strong\u003e. Potential reasons cited by the authors include incorrect data overlay between MRI and ultrasound images, suboptimal image quality, and the small size of the lesions.\u003c\/p\u003e\n\n\u003ch3\u003eReason 2: Out-of-Field Cancers—Lesions Missed on MRI Reading\u003c\/h3\u003e\n\n\u003cp\u003eIn \u003cstrong\u003e32 of 89 cases (36%)\u003c\/strong\u003e where systematic biopsy found a higher-grade cancer, the positive biopsy cores were located entirely \u003cstrong\u003eoutside\u003c\/strong\u003e the MRI target area (out-of-field). This breaks down as 17 GG 1, 10 GG 2, 1 GG 3, 3 GG 4, and 1 GG 5 cases.\u003c\/p\u003e\n\n\u003cp\u003eA detailed analysis of 15 cases with out-of-field clinically significant cancer found several important patterns:\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eImage quality was limited in 9 of 15 cases (60%)\u003c\/strong\u003e — poor image quality was the single most common contributing factor.\u003c\/li\u003e\n  \u003cli\u003eDiffuse changes with no clear focal lesion were described in many reports, making it difficult for radiologists to mark a precise target.\u003c\/li\u003e\n  \u003cli\u003eThe median PSA (4.7 ng\/ml) and PSAD (0.17 ng\/ml²) for these missed cases were higher than in the biopsy-negative group, suggesting more aggressive disease.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eCancers Not Visible on MRI at All\u003c\/h3\u003e\n\n\u003cp\u003eFive patients with PI-RADS 2 on MRI (considered \"low suspicion\") were found to have clinically significant cancer on systematic biopsy—three of these were csPC. Additionally, \u003cstrong\u003efive GG 3 or higher cancers were not identified on MRI at all\u003c\/strong\u003e, and nine of the 19 cases missed on systematic biopsy were located in the \u003cstrong\u003eanterior (front) part of the prostate\u003c\/strong\u003e, an area that is notoriously difficult to sample with standard biopsy approaches.\u003c\/p\u003e\n\n\u003ch3\u003eSystematic Biopsy Misses\u003c\/h3\u003e\n\n\u003cp\u003eIt is equally important to acknowledge that systematic biopsy is not perfect either. In 41 cases, targeted biopsy upgraded the cancer grade. Nineteen of these were cases where systematic biopsy was completely negative. The median maximum lesion diameter for cancers missed on SBx was \u003cstrong\u003e12 mm (IQR 9–13 mm)\u003c\/strong\u003e, and many of these were located anteriorly.\u003c\/p\u003e\n\n\u003ch2 id=\"clinical-implications\"\u003eClinical Implications: What This Means for Patients\u003c\/h2\u003e\n\n\u003cp\u003eThis study provides important evidence about how to best screen younger men for prostate cancer. For men aged 55 years and younger, previous research has shown that an MRI-based pathway—with or without additional biomarkers—reduces unnecessary biopsies and overdiagnosis of insignificant cancers while maintaining detection of clinically significant disease. However, data for men aged 45–55 years have been sparse. This study fills that gap but sounds a cautionary note.\u003c\/p\u003e\n\n\u003cp\u003eThe most important finding is that \u003cstrong\u003etwo-core targeted biopsy alone is not sufficient in this age group\u003c\/strong\u003e. With a miss rate of 33% for clinically significant cancers, relying solely on targeted biopsy would mean that one in three aggressive cancers goes undetected. The fact that many of these missed cancers \u003cem\u003ewere actually visible on MRI\u003c\/em\u003e suggests the problem lies not with MRI as a detection tool, but with the precision of the fusion biopsy technique itself.\u003c\/p\u003e\n\n\u003cp\u003eThe authors note that \"to a large extent, these csPC cases had been identified as a visible lesion on mpMRI by the radiologists. This indicates that despite the great challenges with MRI in this age group, its value is very high, not only for avoiding biopsies but also for correctly identifying lesions.\"\u003c\/p\u003e\n\n\u003cp\u003eImportantly, \u003cstrong\u003emen with smaller prostate volumes were more likely to have a positive biopsy\u003c\/strong\u003e, a finding consistent with the fact that PSA density is higher in these men. The combination of targeted and systematic biopsy provided the most accurate classification of cancer grade in this young population.\u003c\/p\u003e\n\n\u003cp\u003eThe study also underscores that \u003cstrong\u003eMRI reading in young men is challenging\u003c\/strong\u003e and results depend on reader experience. This is why the authors emphasize the need for careful quality control in both imaging and biopsy procedures.\u003c\/p\u003e\n\n\u003ch2 id=\"limitations\"\u003eStudy Limitations: What This Study Could Not Prove\u003c\/h2\u003e\n\n\u003cp\u003eEvery research study has limitations, and the authors were transparent about several important ones:\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eNo centralized MRI review before biopsy:\u003c\/strong\u003e Biopsy decisions were based on local radiologist readings, which may vary in quality and experience. This could overestimate or underestimate the accuracy of MRI-directed biopsy.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eVariability in biopsy technique:\u003c\/strong\u003e Biopsies were performed at four different sites, by different urologists, using different fusion biopsy software systems (Koelis, BiopSee, UroNAV) and either transrectal or transperineal approaches. This real-world variability is a strength for generalizability but makes standardization difficult.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eRetrospective subgroup analysis:\u003c\/strong\u003e The analysis was performed retrospectively on a subgroup of the larger PROBASE cohort, which can introduce selection bias.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eShort follow-up:\u003c\/strong\u003e The study did not have long-term follow-up data to confirm which cancers ultimately would have progressed and caused harm. Some of the \"missed\" cancers may have been slow-growing and never clinically relevant.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eLimited sample size for sub-analyses:\u003c\/strong\u003e While 525 men is a substantial cohort, subgroups such as the 15 out-of-field csPC cases are small, and conclusions drawn from them should be interpreted cautiously.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePossible overdetection of low-risk cancer:\u003c\/strong\u003e The systematic biopsy approach detected 51 low-risk (GG 1) cancers versus 26 for targeted biopsy, raising the question of whether the additional systematic cores lead to unnecessary diagnosis of indolent (harmless) cancers—the very problem MRI was introduced to solve.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eAdditionally, five patients with GG 3 or higher prostate cancer were not identified on MRI, and three of five PI-RADS 2 cases turned out to be clinically significant. These findings suggest that while MRI is powerful, it cannot yet be used alone to rule out aggressive disease in younger men.\u003c\/p\u003e\n\n\u003ch2 id=\"recommendations\"\u003eRecommendations for Patients and Doctors\u003c\/h2\u003e\n\n\u003cp\u003eBased on these findings, the researchers offer several clinically actionable recommendations.\u003c\/p\u003e\n\n\u003col\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCombined biopsy should remain the standard for young men with elevated PSA and suspicious MRI.\u003c\/strong\u003e Given that systematic biopsy alone detected 26% of csPC cases that targeted biopsy completely missed, the two methods are genuinely complementary.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eConsider more targeted cores per lesion.\u003c\/strong\u003e Since many misses occurred because the targeted needle didn't hit the small MRI-visible lesion (median diameter only 10 mm), sampling more cores from the lesion and its immediate surroundings (the \"penumbra\") might significantly reduce miss rates.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eMaintain systematic cores even when MRI is positive.\u003c\/strong\u003e The authors suggest that \"SBx cores or targeted perilesional sampling, particularly in young men with smaller prostate volume, might be a valuable complement to TBx to ensure reliable and early detection of (cs)PC in this age group.\"\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eAddress image quality issues.\u003c\/strong\u003e With limited image quality contributing to 60% of out-of-field misses, quality control standards (such as the PI-QUAL score for MRI quality) should be implemented and reported.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eConsider additional sampling in men with multiple MRI lesions.\u003c\/strong\u003e In 78% of cases where systematic biopsy upgraded cancer to clinically significant status, more than one suspicious area was present on MRI.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eBe aware of hard-to-detect locations.\u003c\/strong\u003e Anterior (front-of-prostate) lesions were a common location for cancers missed by systematic biopsy, and small apical or lateral lesions were common in targeted biopsy misses. Men and their urologists should discuss whether extended biopsy schemes that include these areas are warranted.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003cp\u003eFor patients, the key takeaway is this: \u003cstrong\u003eif you are a man aged 45–54 with an elevated PSA and a suspicious MRI, ask your doctor whether you are receiving both a targeted biopsy of the suspicious lesion and systematic cores from the rest of the prostate.\u003c\/strong\u003e The evidence from this study suggests that doing only the targeted biopsy could leave a significant number of aggressive cancers undetected.\u003c\/p\u003e\n\n\u003c!-- ddn:faq:start --\u003e\n\u003ch2 id=\"ddn-faq\"\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003ch3\u003eWho was studied in this prostate cancer screening trial?\u003c\/h3\u003e\n\u003cp\u003eThe study followed 525 men aged 44–54 with elevated PSA levels (median 3.98 ng\/ml) from the German PROBASE trial. All had a first MRI and combined targeted plus systematic biopsy. Most were around age 50. This group is younger than typical prostate cancer screening populations, and the study focused on how to detect aggressive cancers reliably in them.\u003c\/p\u003e\n\u003ch3\u003eWhy did targeted biopsy alone miss many clinically significant cancers?\u003c\/h3\u003e\n\u003cp\u003eIn 57 of 89 cases where systematic biopsy found a higher-grade cancer, the positive core was inside or next to the MRI-targeted lesion. Many lesions were very small, only about 10 mm wide. In 32 other cases, the cancer was entirely outside the MRI target area, often due to limited image quality or diffuse changes. So the needle often missed the lesion or the MRI missed the cancer entirely.\u003c\/p\u003e\n\u003ch3\u003eWhat were the main detection rates for systematic versus targeted biopsy?\u003c\/h3\u003e\n\u003cp\u003eSystematic biopsy (about 12 cores) detected clinically significant prostate cancer in 139 of 148 cases, or 94%. Targeted biopsy (about 2 cores per lesion) detected only 109 of 148 cases, or 74%. In other words, targeted biopsy missed 33% of significant cancers, while systematic biopsy missed 16%. Adding systematic cores cut the miss rate in half.\u003c\/p\u003e\n\u003ch3\u003eWhat practical advice does the study give to men aged 45–54 with elevated PSA?\u003c\/h3\u003e\n\u003cp\u003eThe researchers recommend that men in this age group receive both targeted biopsy of suspicious MRI lesions and systematic biopsy cores from the rest of the prostate. They also suggest taking more targeted cores per lesion, especially for small lesions, and being aware that anterior cancers may be missed. Ask your doctor if combined biopsy is right for you.\u003c\/p\u003e\n\u003ch3\u003eWhat are the limitations of this study?\u003c\/h3\u003e\n\u003cp\u003eThis was a retrospective subgroup analysis of the larger PROBASE trial with no centralized MRI review. Biopsies were done at four sites using different software and routes. Follow-up was short, so we don't know which cancers would have progressed. Also, the subgroup sizes for some analyses were small. Still, the findings are robust enough to guide practice.\u003c\/p\u003e\n\u003c!-- ddn:faq:end --\u003e\n\n\u003ch2 id=\"source\"\u003eSource Information\u003c\/h2\u003e\n\n\u003cp\u003e\u003cstrong\u003eOriginal Article Title:\u003c\/strong\u003e Value of Additional Systematic Cores During Magnetic Resonance Imaging–guided Targeted Biopsy in Prostate Cancer Screening for Young Men- Results from the PROBASE Trial\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eAuthors:\u003c\/strong\u003e Rouvier Al-Monajjed, Matthias Boschheidgen, Jale Lakes, Agne Krilaviciute, Jan-Philipp Radtke, Heinz-Peter Schlemmer, David Bonekamp, Kathleen Herkommer, Matthias Jahnen, Jürgen E. Gschwend, Daniel Düx, Frank Wacker, Marcus R. Makowski, Andreas Sauterg, Markus A. Kuczyk, Nina Harke, Jürgen Debus, Christoph Grott, Christian Arsova, Petra Seibold, Axel Benner, Boris Hadaschik, Frederik Giesel, Glen Kristiansen, Gerald Antoch, Nikolaus Becker, Rudolf Kaaks, Peter Albers, and Lars Schimmöller\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eJournal:\u003c\/strong\u003e European Urology Oncology (2025), available online at euoncology.europeanurology.com\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003ePublication Details:\u003c\/strong\u003e Published by Elsevier B.V. on behalf of the European Association of Urology. DOI: 10.1016\/j.euo.2025.10.014. Open access article under the CC BY license.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eTrial Registration:\u003c\/strong\u003e ISRCTN37591328\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eNote:\u003c\/strong\u003e This patient-friendly article is based on peer-reviewed research. It has been written to make the study's findings accessible to a general audience while preserving all numerical data, statistical results, and scientific conclusions from the original publication. The first two authors and the last two authors share equal contribution roles as indicated in the original article. This content is for educational purposes and does not constitute medical advice. Patients should discuss their individual screening and diagnostic options with their healthcare providers.\u003c\/p\u003e","brand":"DiagnosticDetectives.Com","offers":[{"title":"Default Title","offer_id":47458210939036,"sku":null,"price":0.0,"currency_code":"EUR","in_stock":true}],"url":"https:\/\/diagnosticdetectives.com.br\/products\/prostate-cancer-screening-in-young-men-why-combining-two-biopsy-methods-improves-detection-results-from-the-probase-trial","provider":"DiagnosticDetectives.Com","version":"1.0","type":"link"}