Merkel cell carcinoma of left upper limb, including shoulder

This code signifies a malignant neuroendocrine tumor, specifically Merkel cell carcinoma, originating in the skin of the patient's left upper extremity, encompassing the shoulder region. This aggressive skin cancer is characterized by rapid growth and a high propensity for metastasis.

Apply this code when documentation clearly states a diagnosis of Merkel cell carcinoma located on the left arm or shoulder. Supporting documentation should include pathology reports confirming Merkel cell carcinoma and a clear anatomical site laterality.

• Ensure the documentation specifies "Merkel cell carcinoma" and not another type of skin cancer.
• Verify laterality (left) and anatomical site (upper limb, including shoulder) are explicitly stated.
• Consider additional codes for any associated metastases or primary tumor sites if present.