C43.121 Malignant melanoma of left upper eyelid, including canthus

Billable ICD-10-CM code, FY2026.

Applies from C43 Malignant melanoma of skin

Excludes1 (never code together)

• melanoma in situ (D03.-)

Excludes2 (not included here)

• malignant melanoma of skin of genital organs (C51-C52, C60.-, C63.-)
• Merkel cell carcinoma (C4A.-)
• sites other than skin-code to malignant neoplasm of the site

Risk adjustment (HCC)

• CMS-HCC V28: HCC 23 — Prostate, Breast, and Other Cancers and Tumors
• CMS-HCC V22: HCC 12 — Breast, Prostate, and Other Cancers and Tumors
• RxHCC V08: HCC 22 — Prostate, Breast, Bladder, and Other Cancers and Tumors
• ESRD V24: HCC 12

MS-DRG index

Defines the logic of DRG(s) 124-125 in MDC 02.

Code annotations containing back-references to C43.121

Back-references to C43.1

• Type 1 Excludes: C69 Malignant neoplasm of eye and adnexa ("malignant neoplasm of eyelid (skin) (C43.1-, C44.1-)")

Back-references to C43

• Type 1 Excludes: C44 Other and unspecified malignant neoplasm of skin ("malignant melanoma of skin (C43.-)")

Nearby codes

• C43.10 Malignant melanoma of unspecified eyelid, including canthus
• C43.11 Malignant melanoma of right eyelid, including canthus
• C43.111 Malignant melanoma of right upper eyelid, including canthus
• C43.112 Malignant melanoma of right lower eyelid, including canthus
• C43.12 Malignant melanoma of left eyelid, including canthus
• C43.121 Malignant melanoma of left upper eyelid, including canthus (this code)
• C43.122 Malignant melanoma of left lower eyelid, including canthus
• C43.2 Malignant melanoma of ear and external auricular canal
• C43.20 Malignant melanoma of unspecified ear and external auricular canal
• C43.21 Malignant melanoma of right ear and external auricular canal
• C43.22 Malignant melanoma of left ear and external auricular canal