By Krystal Harris, DVM Grading – 3-Tier Patnaik vs. 2-tier Kiupel For many years, veterinary pathologists have relied on the Patnaik 3-tier grading system for cutaneous MCTs. When this system was published each tumor grade was associated with a distinct survival curve (Figure 1, Patnaik 1984). In recent studies an increased number of tumors are being.. read more →