C73 Malignant neoplasm of thyroid gland

The ICD-10-CM code for Malignant neoplasm of thyroid gland is C73 (FY2026). It is a billable, claim-ready diagnosis code.

Classification

Chapter

2: Neoplasms (C00-D49)

Section

C73-C75: Malignant neoplasms of thyroid and other endocrine glands (C73-C75)

Category C73

1 code (1 billable)

FY2026 Status

Stable since FY2024

Also Known As

ICD-10-CM Alphabetic Index entries that lead to C73:

• Wuchernde Struma Langhans
• Hurthle cell › adenocarcinoma
• Adenocarcinoma › nonencapsulated sclerosing
• Carcinoma (malignant) › Hurthle cell
• Goiter (plunging) (substernal) › malignant
• Carcinoma (malignant) › nonencapsulated sclerosing
• Goiter (plunging) (substernal) › cancerous
• Adenocarcinoma › Hurthle cell

U.S. Hospital Utilization

• An estimated 20,565 U.S. inpatient stays in 2023 included C73 among the documented diagnoses.
• 8,935 stays listed it as the principal diagnosis.

Source: National Inpatient Sample (NIS), Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality, 2016–2023. National survey-weighted estimates.

Official Coding Guidelines

Tx of primary site (TOC entry)

a. Admission/Encounter for treatment of primary site ............................................................. 33

Tx of secondary site (TOC entry)

b. Admission/Encounter for treatment of secondary site .......................................................... 33

Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026

References

• CMS — ICD-10-CM Official Code Set and Guidelines, FY2026
• CDC/NCHS — ICD-10-CM Files and Browser Tool
• AHRQ — HCUP National Inpatient Sample, Frequencies by Diagnosis Code (2016–2023)