Merkel cell carcinoma of right ear and external auric canal

This code signifies a rare, aggressive neuroendocrine carcinoma originating from Merkel cells, specifically located on the patient's right ear or within the external auditory canal. It is characterized by rapid growth and a high propensity for local recurrence and metastasis.

Apply this code when documentation confirms a diagnosis of Merkel cell carcinoma affecting the right ear or its external canal. This diagnosis is typically established through biopsy and histopathological examination. Use this code for primary tumors in this specific anatomical site.

• Ensure documentation explicitly states "Merkel cell carcinoma" and specifies the right ear or external auricular canal.
• Distinguish from other skin malignancies of the ear, such as squamous cell carcinoma or basal cell carcinoma.
• Code any associated metastatic sites separately using appropriate secondary malignancy codes.