Coding Grade for Colon/Rectum
Histologic grade, differentiation, codes 1 = well differentiated 2 = moderately differentiated 3= poorly differentiated 4= undifferentiated
Grade is the measurement of how closely cancer cells resemble the cells of the organ in which the cancer originated. Code 1 indicates that the cancer cells closely resemble those of the organ of origin. As the grade number increases the resemblance of cancer cells to those of the organ of origin decreases. Grade 4 cancers have little or no resemblance to the cells of the organ of origin. The general code definitions for grade are shown on this slide; 1 is well differentiated, 2 is moderately differentiated, 3 is poorly differentiated, and 4 is undifferentiated.