Internal Medicine Coding Alert

Question: How do I know when to report skin biopsy separately with, or in place of, other procedures such as shaving or excision?

Answer: In general, you may report skin biopsy (11100-11101, Biopsy of skin, subcutaneous tissue and/or mucous membrane [including simple closure], unless otherwise listed ...) separately when the biopsy occurs at a separate location from an excision or other removal or when the results of the biopsy prompt the more extensive removal by excision or other method.

For instance, if your internist excises a lesion on the patient's right hand and biopsies a different lesion (either on the right hand or elsewhere on the body), the excision and biopsy are separate. Append modifier 59 (Distinct procedural service) to the biopsy code to show that it occurred at a different location from the excision.

Don't forget: Biopsy is a standard practice when removing skin lesions. In most cases, you would not report biopsy of the same lesion separately with an excision or other removal. In an alternative scenario, the internist takes a biopsy by shave technique and submits the sample to pathology for examination. The results reveal a malignant lesion, which your internist then removes in its entirety, with margins, by excision. In this case, the biopsy and excision are again separate because the biopsy led to the decision for the excision.

When coding, append modifier 58 (Staged or related procedure or service by the same physician during the postoperative period) to the excision code to show that this was a staged procedure following the biopsy. Because 11100 has 0 global days, the only time this is an issue is when a frozen section is done and the biopsy and treatment are performed on the same day.

Important: Your physician's intent has a lot to do with distinguishing between a biopsy and removal by shaving, excision, or some other method. The AMA has stressed this point, noting, "The intent of a biopsy is to remove a portion of skin, suspect lesion, or entire lesion so that it can be examined pathologically" (CPT Assistant, Vol. 14, Issue 10: Oct. 2004). In contrast, "The intent of other integumentary procedures that involve removal of tissue is different. Generally, they are performed for the purpose of removing the entire lesion."

Because physicians often use the terms "biopsy" and "excision" interchangeably, you may find questioning your doctor on those claims useful when the terminology and intent are unclear.