Tumor grade refers to how much the cancer cells differ from normal cells under a microscope, and it provides information about how aggressively the tumor is likely to behave.

🧠 What does tumor grade indicate? Tumor grade describes the appearance and behavior of cancer cells—how abnormal they look and how quickly they are likely to grow and spread.

🔍 Grading Criteria (Microscopic evaluation): Cell differentiation – How closely cancer cells resemble the normal cells of the same tissue.

Nuclear atypia – Abnormal size, shape, and structure of cell nuclei.

Mitotic rate – How frequently the cells are dividing.

Necrosis – Presence of dead tumor cells (in some grading systems).

📊 Common Tumor Grades: Grade 1 (Low grade): Well-differentiated cells; resemble normal cells; slow-growing.

Grade 2 (Intermediate grade): Moderately differentiated; more abnormal; moderately aggressive.

Grade 3 (High grade): Poorly differentiated or undifferentiated; very abnormal; fast-growing and more likely to spread.

🧬 Examples of Specific Grading Systems: Gleason Score (for prostate cancer)

Bloom-Richardson Grade (for breast cancer)

WHO CNS Tumor Grades (for brain tumors, Grade I to IV)

Would you like the tumor grade definition adapted for a specific tumor type (e.g. glioma, breast cancer)?