What ICD-10-CM code represents secondary malignant neoplasm of skin of the chin?

• A. C79.31
• B. C79.2
• C. C85.16
• D. E86.0

Answer: (B)

The correct code for secondary malignant neoplasm of skin of the chin is C79.31. This code specifically indicates a metastatic cancer that has spread to the skin, particularly at the chin area. ICD-10-CM codes are structured to provide detailed descriptions of various medical conditions, and in the case of neoplasms, the codes distinguish between primary tumors and secondary (metastatic) tumors.

In this instance, C79.31 is selected because it accurately identifies secondary malignancies in the skin. The other codes, while related to neoplasms or skin conditions, do not specifically target the secondary malignant neoplasm at the chin. C79.2 is related to secondary malignant neoplasms without specifying the skin, C85.16 pertains to non-Hodgkin lymphoma, and E86.0 relates to dehydration, none of which would apply to a secondary malignant neoplasm of the skin in that specific area. Thus, C79.31 is the most appropriate code for this scenario.