C4A.5

Header — not billable

Merkel cell carcinoma of trunk

The ICD-10 code for merkel cell carcinoma of trunk is C4A.5.

C4A.5 is a non-billable header code. It groups related conditions but cannot be used on its own for reimbursement — select one of the 3 more specific codes below.

Clinical notes

Excludes2 (not included here)

An Excludes2 note means the excluded condition is not part of this one, but a patient can have both at the same time — in that case both codes may be reported together.

malignant neoplasm of anus NOS (C21.0)
malignant neoplasm of scrotum (C63.2)

Documentation support

General coding-documentation guidance — not a substitute for payer-specific requirements or professional coding judgment.

•This is a non-billable header code. Documentation must support a more specific child code before this diagnosis can be reported on a claim.
•As a general rule, code to the highest level of specificity supported by the documentation in the medical record.

C4A.5

Clinical notes

Excludes2 (not included here)

Documentation support

Child codes under C4A.5

Related codes in this category