What is Gleason's grading of prostate hx?

• Grading based on the architectural resemblance to benign glands, low- medium magnification • 5-tier grades (patterns) • Remains as the single most important prognostic parameter • Used in all risk stratification tools for treatment decision Gleason grade 3 (Frequent, Small well differenciated or sharpened Glands, Infiltrative, No fusion no cribriform pattern) Gleason grade 4 (Fused, Cribriform, Poorly formed glands, Glomeruloid frequent) Gleason grade 5 (No glandular differenciation, No glandular lumen, Isolated cells, Comedocarcinoma patterns, Solid nests)