D36.9 (Benign neoplasm, unspecified site) compared with D48.9 (Neoplasm of uncertain behavior, unspecified), from the official CMS tabular data. D36.9 and D48.9 name the same anatomical site (unspecified site) with a different neoplasm behavior.
Same anatomical site, different neoplasm behavior.
Same site — uncertain behavior (unspecified site)
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. D36.9 and D48.9 name the same anatomical site (unspecified site) 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.
| D36.9Benign neoplasm, unspecified site | D48.9Neoplasm of uncertain behavior, unspecified | |
|---|---|---|
| Billing status | Billable | Billable |
| Classification | C00-D49 — Neoplasms (C00-D49) | C00-D49 — Neoplasms (C00-D49) |
| Definition | Benign neoplasm, unspecified site is a billable ICD-10-CM diagnosis code (D36.9). | Neoplasm of uncertain behavior, unspecified is a billable ICD-10-CM diagnosis code (D48.9). |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources