C37 — Malignant neoplasm of thymus
Is C37 billable?
Yes — C37 is billable for FY2027. C37 is a valid, billable ICD-10-CM code at the highest level of specificity in its branch. C37 may be submitted for encounters from October 1, 2026 through September 30, 2027.
C37 at a glance
| Code | C37 |
|---|---|
| Description | Malignant neoplasm of thymus |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
Which MS-DRGs does C37 group to?
C37 sits in MDC 17 and helps define the logic of 3 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 826Myeloproliferative Disorders or Poorly Differentiated Neoplasms with Major O.R. Procedures with MCCsurgical
- 827Myeloproliferative Disorders or Poorly Differentiated Neoplasms with Major O.R. Procedures with CCsurgical
- 828Myeloproliferative Disorders or Poorly Differentiated Neoplasms with Major O.R. Procedures without CC/MCCsurgical
As a secondary diagnosis, C37 is a complication or comorbidity (CC), which can move a stay into a higher-paying DRG.
How is C37 listed in the Alphabetic Index?
These are the routes through the Alphabetic Index that lead to C37. They show the wording a clinician may have documented, which often differs from the Tabular description.
- Carcinoma › thymic (malignant)
- Thymoma › malignant
- Thymoma › metaplastic
- Thymoma › sclerosing
- Thymoma › type A
- Thymoma › type AB
- Thymoma › type B1
- Thymoma › type B2
- Thymoma › type B3
Excludes1 — never code together
The conditions below can never be reported together with C37 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
- malignant carcinoid tumor of the thymus (C7A.091)
Excludes1 — never code together — inherited from C30-C39
The conditions below can never be reported together with C37 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
- mesothelioma (C45.-)
How long has C37 existed?
C37 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.
Which codes are confused with C37?
ICD-10-CM declares these codes mutually exclusive with C37 — exactly one of each pair can be correct for a given encounter.