ICD-10-CM 2027 diagnosis code
C44.509Unspecified malignant neoplasm of skin of other part of trunk
C44.509 is a valid, billable ICD-10-CM code for unspecified malignant neoplasm of skin of other part of trunk. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.Short description: Unsp malignant neoplasm of skin of other part of trunk
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 C44.509
C44.509 is the ICD-10-CM diagnosis code for unspecified malignant neoplasm of skin of other part of trunk. 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 C44.50, choose C44.509 (skin of other part of trunk) only when documentation doesn't support a more specific option: anal skin (C44.500) and skin of breast (C44.501).
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 173.50 (unspecified malignant neoplasm of skin of trunk, except scrotum).
Notes that apply from higher levels
Instructions written at a parent level also apply to C44.509.
Broader instructions also apply from Chapter 2: Neoplasms.
Table of Drugs & Neoplasms entries
- Neoplasm, neoplastic › abdomen, abdominal › wall — Malignant Primary
- Neoplasm, neoplastic › abdomen, abdominal › wall › skin — Malignant Primary
- Neoplasm, neoplastic › axilla, axillary › fold — Malignant Primary
- Neoplasm, neoplastic › nates — Malignant Primary
- Neoplasm, neoplastic › skin NOS › abdominal wall — Malignant Primary
- Neoplasm, neoplastic › skin NOS › axilla, axillary fold — Malignant Primary
- Neoplasm, neoplastic › skin NOS › back — Malignant Primary
- Neoplasm, neoplastic › skin NOS › buttock — Malignant Primary
- Neoplasm, neoplastic › skin NOS › chest (wall) — Malignant Primary
- Neoplasm, neoplastic › skin NOS › clavicular area — Malignant Primary
- Neoplasm, neoplastic › skin NOS › flank — Malignant Primary
- Neoplasm, neoplastic › skin NOS › gluteal region — Malignant Primary
- Neoplasm, neoplastic › skin NOS › groin — Malignant Primary
- Neoplasm, neoplastic › skin NOS › infraclavicular region — Malignant Primary
- Neoplasm, neoplastic › skin NOS › inguinal region — Malignant Primary
- Neoplasm, neoplastic › skin NOS › nates — Malignant Primary
- Neoplasm, neoplastic › skin NOS › pubes — Malignant Primary
- Neoplasm, neoplastic › skin NOS › sacrococcygeal region — Malignant Primary
- Neoplasm, neoplastic › skin NOS › scapular region — Malignant Primary
- Neoplasm, neoplastic › skin NOS › submammary fold — Malignant Primary
- Neoplasm, neoplastic › skin NOS › thoracic wall — Malignant Primary
- Neoplasm, neoplastic › skin NOS › trunk — Malignant Primary
- Neoplasm, neoplastic › skin NOS › umbilicus — Malignant Primary
- Neoplasm, neoplastic › umbilicus, umbilical — 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 →- 173.50Unspecified malignant neoplasm of skin of trunk, except scrotumapproximate
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 C44.509
Is C44.509 billable?
- Yes. C44.509 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can C44.509 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict C44.509 as a principal diagnosis.
Is C44.509 a CC or MCC?
- No. C44.509 is neither a CC nor an MCC under MS-DRG v44.0.
What DRG does C44.509 group to?
- C44.509 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 C44.509?
- The CMS General Equivalence Mappings map C44.509 to ICD-9-CM 173.50.