N63.1 (Unspecified lump in the right breast) compared with N63.2 (Unspecified lump in the left breast), from the official CMS tabular data. N63.1 and N63.2 code the same condition on opposite sides. MedCoder-derived
Same condition; these differ only in which side is documented.
These codes share a category and title and differ only in the side affected. The documentation decides which applies, and a bilateral code is reported only where the code set provides one.
Source: ICD-10-CM tabular list (laterality variant derived from the code title)
Same condition, opposite side. N63.1 and N63.2 name the same condition on opposite sides of the body.
Same category and title, differing only in which side is affected — the documentation decides which one applies, and a bilateral code is reported only where the code set provides one.
| N63.1Unspecified lump in the right breast | N63.2Unspecified lump in the left breast | |
|---|---|---|
| Billing status | Non-billable header | Non-billable header |
| Classification | N00-N99 — Diseases of the genitourinary system | N00-N99 — Diseases of the genitourinary system |
| Definition | Unspecified lump in the right breast is a non-billable ICD-10-CM category code (N63.1). | Unspecified lump in the left breast is a non-billable ICD-10-CM category code (N63.2). |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources