C79.89 (Secondary malignant neoplasm of other specified sites) compared with D00.05 (Carcinoma in situ of hard palate), from the official CMS tabular data. C79.89 and D00.05 name the same anatomical site (palate) with a different neoplasm behavior.
Same anatomical site, different neoplasm behavior.
Same site — carcinoma in situ (palate)
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. C79.89 and D00.05 name the same anatomical site (palate) with a different neoplasm behavior.
From the CMS 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.
| C79.89Secondary malignant neoplasm of other specified sites | D00.05Carcinoma in situ of hard palate | |
|---|---|---|
| Billing status | Billable | Billable |
| Classification | C00-D49 — Neoplasms (C00-D49) | C00-D49 — Neoplasms (C00-D49) |
| Definition | Secondary malignant neoplasm of other specified sites is a billable ICD-10-CM diagnosis code (C79.89). | Carcinoma in situ of hard palate is a billable ICD-10-CM diagnosis code (D00.05). |
| Includes | — | Bowen's disease erythroplasia grade III intraepithelial neoplasia Queyrat's erythroplasia |
| Use additional code | — | code to identify: exposure to environmental tobacco smoke (Z77.22) exposure to tobacco smoke in the perinatal period (P96.81) |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources