Question: How can we report the diagnosis for bone metastasis in a patient who has Merkel cell carcinoma?.
Answer: For bone metastasis, you report ICD-9 code 198.5 (Secondary malignant neoplasm of bone and bone marrow). This code applies for metastasis of bone and bone marrow.
ICD-10 options: When reporting bone metastasis in ICD-10, you have specific codes for bone and bone marrow. Make sure your physician documents if the metastases are in the bone or the marrow. Accordingly, you select from the following two codes:
C79.51, Secondary malignant neoplasm of bone
Also, report the primary neoplasm: In addition to the metastasis, you can submit diagnosis codes for Merkel cell carcinoma. According to the site of the Merkel cell carcinoma, you report ICD-9 codes from 209.31 (Merkel cell carcinoma of the face) through 209.36 (Merkel cell carcinoma of other sites).
C79.52, Secondary malignant neoplasm of bone marrow