Histology Coding Rules: Colon/Rectum
5. (Continued) Example: Rectosigmoid colon, 2 lesions
2) mucin-producing adenocarcinoma 8481/3
Answer: Mucin-producing adenocarcinoma 8481/3
Example: The patient has two lesions in the rectosigmoid colon. The first lesion is adenocarcinoma, an NOS term, and the second lesion is mucin-producing adenocarcinoma, a specific description of the same histology. Because the two lesions are in the same site and one is an NOS histology and the other is a specific description of the same histology, this is counted as one primary and mucin- producing adenocarcinoma (8481/3) is recorded as the histology because it is more specific.