ICD-10-CM 2027 diagnosis code
C44.99Other specified malignant neoplasm of skin, unspecified
C44.99 is a valid, billable ICD-10-CM code for other specified malignant neoplasm of skin, unspecified. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.
Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data
About C44.99
C44.99 is the ICD-10-CM diagnosis code for other specified malignant neoplasm of skin, unspecified. It belongs to category C44 (other and unspecified malignant neoplasm of skin), block C43-C44 (melanoma and other malignant neoplasms of skin) and chapter 2 (neoplasms). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.
Within C44.9, choose C44.99 (Other specified malignant neoplasm of skin, unspecified) only when documentation doesn't support a more specific option: unspecified malignant neoplasm of skin, unspecified (C44.90), basal cell carcinoma of skin, unspecified (C44.91) and squamous cell carcinoma of skin, unspecified (C44.92).
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 606 (Minor Skin Disorders with MCC, relative weight 1.5728) and DRG 607 (Minor Skin Disorders without MCC, relative weight 0.8772), in MDC 09 (Diseases and Disorders of the Skin, Subcutaneous Tissue and Breast), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.
Before ICD-10, this condition was coded in ICD-9-CM as 173.99 (other specified malignant neoplasm of skin, site unspecified).
Notes that apply from higher levels
Instructions written at a parent level also apply to C44.99.
Broader instructions also apply from Chapter 2: Neoplasms.
Alphabetic index entries
2 entriesTerms in the official ICD-10-CM index that lead to C44.99.
Table of Drugs & Neoplasms entries
- Neoplasm, neoplastic › skin NOS › specified type NEC — Malignant Primary
MS-DRG v44.0 grouping
All DRGs →Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.
MDC 09 · Diseases and Disorders of the Skin, Subcutaneous Tissue and Breast
ICD-9-CM equivalent
Converter →- 173.99Other specified malignant neoplasm of skin, site unspecifiedexact
From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
- No changes since FY2016.
Common questions about C44.99
Is C44.99 billable?
- Yes. C44.99 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can C44.99 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict C44.99 as a principal diagnosis.
Is C44.99 a CC or MCC?
- No. C44.99 is neither a CC nor an MCC under MS-DRG v44.0.
What DRG does C44.99 group to?
- C44.99 is used in the MS-DRG v44.0 logic for MS-DRG 606 (Minor Skin Disorders with MCC) and MS-DRG 607 (Minor Skin Disorders without MCC). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.
What is the ICD-9 code for C44.99?
- The CMS General Equivalence Mappings map C44.99 to ICD-9-CM 173.99.