Basal cell carcinoma of overlapping sites of skin

This code signifies a malignant neoplasm originating from the basal cells of the epidermis, specifically when the tumor spans across two or more contiguous anatomical sites of the skin. It indicates a primary skin cancer that has not yet metastasized to distant sites.

Apply this code when documentation clearly identifies a basal cell carcinoma affecting multiple adjacent skin regions, such as a lesion extending from the cheek to the nose, or from the scalp to the forehead. Pathological confirmation of basal cell carcinoma is essential, along with a physician's note detailing the overlapping anatomical involvement.

• Ensure the documentation explicitly states "overlapping sites" or describes the lesion spanning multiple contiguous areas.
• Do not use this code for basal cell carcinoma confined to a single anatomical site; instead, use the more specific C44.xx code for that site.
• Confirm the diagnosis is basal cell carcinoma and not another type of skin cancer, such as squamous cell carcinoma (C44.xx) or melanoma (C43.xx).