ICD-10-CM 2027
ICD-10 code for substernal thyroid
From the official ICD-10-CM alphabetic index entry “Substernal thyroid”. Page updated September 29, 2026.
About coding substernal thyroid
The ICD-10-CM code for substernal thyroid is E04.9 (Nontoxic goiter, unspecified). The official index lists 1 more specific code, so check the documentation for details such as type, cause, site or severity before settling on E04.9.
Within E04, choose E04.9 (Nontoxic goiter, unspecified) only when documentation doesn't support a more specific option: nontoxic diffuse goiter (E04.0), nontoxic single thyroid nodule (E04.1), nontoxic multinodular goiter (E04.2) and other specified nontoxic goiter (E04.8).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 643 (Endocrine Disorders with MCC, relative weight 1.6139), DRG 644 (Endocrine Disorders with CC, relative weight 1.0044) and DRG 645 (Endocrine Disorders without CC/MCC, relative weight 0.7459), in MDC 10 (Endocrine, Nutritional and Metabolic Diseases and Disorders), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
More specific substernal thyroid codes (official index)
- congenital Q89.2 — Congenital malformations of other endocrine glands
Common questions about substernal thyroid ICD-10 codes
What is the ICD-10 code for substernal thyroid?
- E04.9 — Nontoxic goiter, unspecified. More specific codes apply when the documentation supports them: Q89.2.
What is the ICD-10 code for congenital substernal thyroid?
- Q89.2 — Congenital malformations of other endocrine glands.
Is E04.9 billable?
- Yes. E04.9 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can E04.9 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict E04.9 as a principal diagnosis.
Is E04.9 a CC or MCC?
- No. E04.9 is neither a CC nor an MCC under MS-DRG v44.0.