Researchers measured total Gleason pattern 4 length across systematic and MRI-targeted biopsy cores in 2499 men with Grade Group 2-4 prostate cancer who went on to radical prostatectomy, and compared it with current risk-group criteria as a predictor of adverse pathology and 5-year biochemical recurrence. Men with under 2 mm of pattern 4 had 5.2% adverse pathology and 20% 5-year recurrence, indistinguishable from favourable intermediate-risk disease, and 73% of Grade Group 2 cases fell below that threshold. Applied as an eligibility rule it would roughly double the number classed as suitable for active surveillance, though the authors say the quantification method and cut-point still need defining.
Why it is interesting: A quantitative biopsy measure that would reclassify a large share of Grade Group 2 disease, 73% of which fell below the 2 mm threshold.