Histology Coding Rules: Colon/Rectum
Example: Lesion of sigmoid colon, tubular carcinoma in situ and carcinoma
Tubular carcinoma in situ
Answer: 8211/3 Tubular carcinoma
Example: The single lesion of the sigmoid colon contains tubular carcinoma in situ, a specific histology with in situ behavior, and carcinoma, a malignant NOS histology. The exception to rule 2 states to code the specific histology, in this case tubular carcinoma, and to code the malignant behavior from the NOS histology. So, the correct code is 8211/3, tubular carcinoma.