Malignant melanoma of skin of lower limb, including hip

This code identifies a primary malignant melanoma originating in the skin of the lower extremity, encompassing the hip, thigh, knee, lower leg, ankle, and foot. It signifies a cancerous growth of melanocytes, the pigment-producing cells, within the dermal or epidermal layers of the skin in this specific anatomical region.

Assign this code when documentation confirms a diagnosis of malignant melanoma located anywhere on the lower limb, including the hip. Supporting documentation should include pathology reports confirming melanoma and clear anatomical site identification (e.g., "melanoma of left thigh," "melanoma of right ankle").

• Differentiate from melanoma of the trunk (172.5) or upper limb (172.6) based on precise anatomical site.
• Ensure the pathology report explicitly states "malignant melanoma" and not a benign nevus or other skin lesion.
• Do not use for secondary malignant melanoma (metastatic disease); this code is for the primary site.