Squamous cell carcinoma of overlapping sites of skin

This code signifies a malignant neoplasm originating from squamous cells that affects multiple, contiguous, or overlapping anatomical sites of the skin. It indicates that the primary tumor spans across boundaries of distinct skin regions, making it impossible to assign to a single, specific site.

Apply this code when documentation clearly states squamous cell carcinoma involving overlapping skin sites, such as a lesion extending from the cheek to the ear, or from the trunk to an extremity. The physician's notes must explicitly describe the involvement of multiple, adjacent skin areas.

• Ensure the documentation specifies "overlapping sites" or similar language indicating involvement of more than one distinct skin region.
• Do not use if the carcinoma is confined to a single, well-defined skin site; instead, use a more specific code for that anatomical location.
• Confirm the histology is explicitly stated as squamous cell carcinoma.