2026 ICD-10-CM Diagnosis Code C44.121Squamous cell carcinoma of skin of unspecified eyelid, including canthus

ICD-10-CM CodesC00–D49C43-C44C44

ICD-10-CM C44.121
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

C44.121 is a billable ICD-10-CM diagnosis code for squamous cell carcinoma of skin of unspecified eyelid, including canthus. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 124 through 125. Coders also document this condition as squamous cell carcinoma of eyelid. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Skin cancers - squamous cell carcinoma.

Code Identity

ICD-10-CM Code
C44.121
Billable Status
Yes — Valid for Submission
Code Describes
Squamous cell carcinoma of skin of unspecified eyelid, including canthus
Short Description
Squamous cell carcinoma skin/ unsp eyelid, including canthus
Parent Code
Squamous cell carcinoma of skin of eyelid, including canthus

Code Classification

ChapterC00–D49Neoplasms
SectionC43-C44Melanoma and other malignant neoplasms of skin
CategoryC44Other and unspecified malignant neoplasm of skin
This CodeC44.121Squamous cell carcinoma of skin of unspecified eyelid, including canthus

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Squamous cell carcinoma of eyelid

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR NEO027
Skin cancers - squamous cell carcinoma
Default principal diagnosis: inpatient Yes · outpatient Yes

Table of NeoplasmsClinical

Anatomical sites in the Table of Neoplasms that reference this code family.

SiteMalig.
Primary
Malig.
Secondary
Ca
in situ
BenignUncertainUnspec.
canthus (eye) (inner) (outer) squamous cell carcinomaC44.12
eyelid (lower) (skin) (upper) squamous cell carcinomaC44.12
lid (lower) (upper) squamous cell carcinomaC44.12
meibomian gland squamous cell carcinomaC44.12
palpebra squamous cell carcinomaC44.12
skin NOS canthus (eye) (inner) (outer) squamous cell carcinomaC44.12
skin NOS eyelid squamous cell carcinomaC44.12
skin NOS lid (lower) (upper) squamous cell carcinomaC44.12
skin NOS palpebra squamous cell carcinomaC44.12

Patient EducationClinical

Eyelid Disorders

Your eyelids help protect your eyes. When you blink, your eyelids spread moisture over your eyes. Blinking also helps move dirt or other particles off the surface of the eye. You close your eyelids when you see something coming toward your eyes. This can help protect against injuries.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert C44.121 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
173.12 Squam cell ca lid/canth
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About C44.121Overview

Is C44.121 (Squamous cell carcinoma of skin of eyelid, including canthus) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report squamous cell carcinoma of skin of unspecified eyelid, including canthus on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does C44.121 group to?

When squamous cell carcinoma of skin of unspecified eyelid, including canthus is the principal diagnosis on an inpatient stay, it groups to MS-DRG 124, 125, with relative weights from 0.7678 to 1.3231 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of C44.121?

Under the General Equivalence Mappings, squamous cell carcinoma of skin of unspecified eyelid, including canthus converts to ICD-9-CM 173.12 (squam cell ca lid/canth). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.