2026 ICD-10-CM Diagnosis Code C44.80Unspecified malignant neoplasm of overlapping sites of skin

ICD-10-CM Codes›C00–D49›C43-C44›C44

ICD-10-CM C44.80
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

C44.80 is a billable ICD-10-CM diagnosis code for unspecified malignant neoplasm of overlapping sites of skin. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 606 through 607. Coders also document this condition as overlapping malignant neoplasm of skin. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Skin cancers - all other types.

Code Identity

ICD-10-CM Code
C44.80
Billable Status
Yes — Valid for Submission
Code Describes
Unspecified malignant neoplasm of overlapping sites of skin
Short Description
Unspecified malignant neoplasm of overlapping sites of skin
Same as the full description in the CMS dataset.
Parent Code
C44.8
Other and unspecified malignant neoplasm of overlapping sites of skin

Code Classification

ChapterC00–D49Neoplasms
SectionC43-C44Melanoma and other malignant neoplasms of skin
CategoryC44Other and unspecified malignant neoplasm of skin
This CodeC44.80Unspecified malignant neoplasm of overlapping sites of skin

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Overlapping malignant neoplasm of skin

Clinical ClassificationClinical

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

CCSR NEO028
Skin cancers - all other types
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.
skin NOS › overlapping lesionC44.80–––––
skin NOS › specified sites NECC44.80C79.2D04.8D23.9D48.5D49.2

Patient EducationClinical

Skin Cancer

Skin cancer is the most common form of cancer in the United States. The two most common types are basal cell cancer and squamous cell cancer. They usually form on the head, face, neck, hands, and arms. Another type of skin cancer, melanoma, is more dangerous but less common.

Read the full article at MedlinePlus

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

Convert C44.80 to ICD-9-CMHistory

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

ICD-9-CM
173.80 Mal neo skn site NEC/NOS
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 C44.80Overview

Is C44.80 a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report unspecified malignant neoplasm of overlapping sites of skin on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does C44.80 group to?

When unspecified malignant neoplasm of overlapping sites of skin is the principal diagnosis on an inpatient stay, it groups to MS-DRG 606, 607, with relative weights from 0.9064 to 1.5132 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of C44.80?

Under the General Equivalence Mappings, unspecified malignant neoplasm of overlapping sites of skin converts to ICD-9-CM 173.80 (mal neo skn site NEC/NOS). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.