In the Kiupel grade scheme, what was the MST for high-grade tumors?

• A. MST not reached
• B. MST = 89 days
• C. MST = 211 days
• D. MST = 120 days

Answer: (D)

In this question the key idea is how the Kiupel two-tier grading system for canine lymphoma relates histologic grade to prognosis. Kiupel’s scheme divides lymphomas into low-grade and high-grade categories based on specific histopathologic features, and this grading correlates with how aggressively the disease behaves and how long dogs tend to survive.

High-grade lymphomas show more aggressive biology—rapid cell turnover, greater dissemination, and poorer response to therapy—so the median survival time tends to be shorter. The value most consistently reported for high-grade tumors under the Kiupel scheme is about 120 days, reflecting that poorer prognosis compared with low-grade disease.

So, when you see a figure around 120 days for high-grade tumors in the Kiupel framework, it aligns with the expected outcome for this more aggressive category.