C58 (Malignant neoplasm of placenta) compared with D49.59 (Neoplasm of unspecified behavior of other genitourinary organ), from the official CMS tabular data. C58 and D49.59 name the same anatomical site (fetal membrane) with a different neoplasm behavior. MedCoder-derived
Same anatomical site, different neoplasm behavior.
Same site — primary malignancy (fetal membrane)
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. D49.59 and C58 name the same anatomical site (fetal membrane) 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.
| C58Malignant neoplasm of placenta | D49.59Neoplasm of unspecified behavior of other genitourinary organ | |
|---|---|---|
| Billing status | Billable | Billable |
| Classification | C00-D49 — Neoplasms | C00-D49 — Neoplasms |
| Definition | Malignant neoplasm of placenta is a billable ICD-10-CM diagnosis code (C58). | Neoplasm of unspecified behavior of other genitourinary organ is a billable ICD-10-CM diagnosis code (D49.59). |
| Includes | choriocarcinoma NOS chorionepithelioma NOS malignant neoplasm of skin of female genital organs | '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