C78.5 (Secondary malignant neoplasm of large intestine and rectum) compared with D12.6 (Benign neoplasm of colon, unspecified), from the official CMS tabular data. C78.5 and D12.6 name the same anatomical site (intestine) with a different neoplasm behavior. MedCoder-derived
Same anatomical site, different neoplasm behavior.
Same site — benign neoplasm (intestine)
The behavior documented for the site — malignant primary, secondary, carcinoma in situ, benign, uncertain or unspecified — decides which column of the neoplasm table, and therefore which code, applies.
Source: CMS Table of Neoplasms
Same site, different neoplasm behavior. C78.5 and D12.6 name the same anatomical site (intestine) with a different neoplasm behavior.
From the CMS/CDC Table of Neoplasms: the behavior documented for that site — malignant primary, secondary, carcinoma in situ, benign, uncertain or unspecified — decides which column, and therefore which code, applies.
| C78.5Secondary malignant neoplasm of large intestine and rectum | D12.6Benign neoplasm of colon, unspecified | |
|---|---|---|
| Billing status | Billable | Billable |
| Classification | C00-D49 — Neoplasms | C00-D49 — Neoplasms |
| Definition | Secondary malignant neoplasm of large intestine and rectum is a billable ICD-10-CM diagnosis code (C78.5). | Benign neoplasm of colon, unspecified is a billable ICD-10-CM diagnosis code (D12.6). |
| Includes | — | Adenomatosis of colon Benign neoplasm of large intestine NOS Polyposis (hereditary) of colon |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources