Merkel cell carcinoma of left lower limb, including hip

This code signifies a rare and aggressive neuroendocrine carcinoma of the skin, specifically Merkel cell carcinoma, located on the patient's left lower limb, which includes the hip region. This malignancy originates from Merkel cells, which are mechanoreceptors found in the basal layer of the epidermis.

Apply this code when documentation clearly states a confirmed diagnosis of Merkel cell carcinoma affecting any part of the left lower extremity, including the hip. This diagnosis is typically established through biopsy and histopathological examination.

• Ensure laterality (left) and specific body site (lower limb, including hip) are explicitly documented.
• Distinguish from other skin malignancies like squamous cell carcinoma or melanoma, which have different ICD-10-CM codes.
• Code any associated metastases separately, following primary site coding guidelines.