C43.9
BillableMalignant melanoma of skin, unspecified
HCC Category Mapping
V28HCC 23 — Melanoma and Other Skin Cancers
0.251V24HCC 12 — Breast, Prostate, and Other Cancers and Tumors
0.150ESRDHCC 12 — Breast, Prostate, and Other Cancers and Tumors
0.000RxHCCHCC 22 — Cancer, Other Specified Sites
0.000What This Code Means
A malignant (cancerous) melanoma of the skin when the specific location is not documented or specified.
Coding Tips
- •Use this code only when the anatomical site of the melanoma is unknown or unspecified; if location is documented, use a more specific C43 code
- •Melanoma is a serious form of skin cancer; ensure complete documentation of site, depth, and stage for optimal coding accuracy
Clinical Significance
Malignant melanoma of skin, unspecified site. This is the least specific melanoma code and should only be used when the anatomic site truly cannot be determined from any available documentation. This often occurs with melanoma of unknown primary or when records are incomplete. Provider query should always be attempted before using this code.
Documentation Requirements
- ✓Provider query for specific body site — this code represents documentation deficiency
- ✓Histologic confirmation of melanoma (invasive, not in situ)
- ✓Any clinical information suggesting primary site
- ✓Staging information if available
- ✓Treatment plan and disease status
- ✓Reason the site cannot be determined
Commonly Confused Codes
C43.0-C43.72 — Site-specific melanoma codes; always preferred over unspecifiedC43.8 — Melanoma of overlapping sites; different from unspecifiedD03.9 — Melanoma in situ, unspecified; for non-invasive melanoma of unknown siteC80.1 — Malignant (primary) neoplasm, unspecified; for completely unspecified cancer type and site