Dermatology Coding Alert

Question: What is the proper ICD-9 code for dysplastic nevus?

Illinois Subscriber

Answer: You won't find any specific diagnosis code for dysplastic nevus. ICD-9 considers this a neoplasm of uncertain behavior due to the nature of the lesion. Therefore, the proper code would be 238.2 (Neoplasm of uncertain behavior of skin).

Misconstrued: You can only code 238.2 if the pathologist who examines the sample states that the lesion exhibits uncertain behavior, not when the physician thinks it might be. Make sure the lesion gets histologically assessed before resorting to 238.2.

If your dermatologist performed re-excision, you should base the re-excision size reported on the size of the margins excised. Due to the fact that a dysplastic nevus is of uncertain behavior, it is not a malignant lesion. Thus, the excision of benign lesion codes would be appropriate and not the excision of malignant lesion codes.