C37 (Malignant neoplasm of thymus) compared with Z85.238 (Personal history of other malignant neoplasm of thymus), from the official CMS tabular data. Z85.238 is the personal-history/screening code for the active disease C37 names. MedCoder-derived
Personal-history or screening code versus the active disease.
Active disease for this site (thymus)
A personal-history code describes a condition that no longer exists and is no longer being treated, so it is not interchangeable with the active-disease code for the same site.
Source: CMS Table of Neoplasms (site match derived from the code title)
History or screening versus active disease. Z85.238 is the personal-history or screening code for the active disease C37 names.
Site match derived from the code’s own title against the CMS Table of Neoplasms. A personal-history code describes a condition that no longer exists and is no longer being treated, so it is not interchangeable with the active-disease code.
| C37Malignant neoplasm of thymus | Z85.238Personal history of other malignant neoplasm of thymus | |
|---|---|---|
| Billing status | Billable | Billable |
| Classification | C00-D49 — Neoplasms | Z00-Z99 — Factors influencing health status and contact with health services |
| Definition | Malignant neoplasm of thymus is a billable ICD-10-CM diagnosis code (C37). | Personal history of other malignant neoplasm of thymus is a billable ICD-10-CM diagnosis code (Z85.238). |
| Includes | malignant neoplasm of middle ear | Conditions classifiable to C37 |
| Use additional code | — | code to identify: alcohol use and dependence (F10.-) exposure to environmental tobacco smoke (Z77.22) |
| Code first | — | any follow-up examination after treatment of malignant neoplasm (Z08) |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources