D32.1 (Benign neoplasm of spinal meninges) compared with D42.1 (Neoplasm of uncertain behavior of spinal meninges), from the official CMS tabular data. D32.1 and D42.1 name the same anatomical site (arachnoid) with a different neoplasm behavior.
Same anatomical site, different neoplasm behavior.
Same site — uncertain behavior (arachnoid)
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. D32.1 and D42.1 name the same anatomical site (arachnoid) 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.
| D32.1Benign neoplasm of spinal meninges | D42.1Neoplasm of uncertain behavior of spinal meninges | |
|---|---|---|
| Billing status | Billable | Billable |
| Classification | C00-D49 — Neoplasms (C00-D49) | C00-D49 — Neoplasms (C00-D49) |
| Definition | Benign neoplasm of spinal meninges is a billable ICD-10-CM diagnosis code (D32.1). | Neoplasm of uncertain behavior of spinal meninges is a billable ICD-10-CM diagnosis code (D42.1). |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources