Gastroenterology Coding Alert

Question: Our GI physician performed an ileum biopsy, and the pathology report notes a diagnosis of “malignant carcinoid tumor,” with code C17.2 – is that correct?

Nevada Subscriber

Answer: No, C17.2 (Malignant neoplasm of ileum) is not the correct diagnosis code for a malignant carcinoid tumor.

Despite the fact that malignant carcinoid tumor is a malignant neoplasm, code C17.2 has an Excludes 1 note listed under the parent code for malignant carcinoid tumors of the small intestine that refers coders to C7A.0.

In this case, you should report the diagnosis as C7A.012 (Malignant carcinoid tumor of the ileum).

Find ‘A’ codes: Although original ICD-10-CM codes all had the first digit as an alpha character followed by second, third and fourth characters that were numeric, updates have required changing some of these rules to allow expansion of the code set.

As to where to find these codes, they’re still generally in numeric order. For instance, C7A lies between C75- and C7B.- followed by C76-. The reason for using the “A” and “B” in the third character in these codes is that C75- codes with numerals 0-9 in the third character already existed.