C78.2 (Secondary malignant neoplasm of pleura) compared with D49.1 (Neoplasm of unspecified behavior of respiratory system), from the official CMS tabular data. C78.2 and D49.1 name the same anatomical site (pleura) with a different neoplasm behavior. MedCoder-derived
Same anatomical site, different neoplasm behavior.
Same site — secondary malignancy (pleura)
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. D49.1 and C78.2 name the same anatomical site (pleura) 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.
| C78.2Secondary malignant neoplasm of pleura | D49.1Neoplasm of unspecified behavior of respiratory system | |
|---|---|---|
| Billing status | Billable | Billable |
| Classification | C00-D49 — Neoplasms | C00-D49 — Neoplasms |
| Definition | Secondary malignant neoplasm of pleura is a billable ICD-10-CM diagnosis code (C78.2). | Neoplasm of unspecified behavior of respiratory system is a billable ICD-10-CM diagnosis code (D49.1). |
| Includes | — | 'growth' NOS neoplasm NOS new growth NOS tumor NOS |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources