Dermatology Coding Alert

Question: Would you please explain the difference between code 11100 and the excision codes (11400-11646)? Also, what should I code for a punch biopsy? Would code 11100 apply, or should I report the excision codes (11400-11646) for this procedure?

Arkansas Subscriber

Answer: It's important to understand this difference. A biopsy is a sampling of a piece of tissue, whether it is skin, organ, or other body tissue. In contrast, an excision is the cutting out or cutting away of an entire lesion.

Code 11100 (Biopsy of skin, subcutaneous tissue and/or mucous membrane [including simple closure], unless otherwise listed; single lesion) is strictly a biopsy code. Codes 11400-11646 are excision codes for the removal of benign and malignant lesions, which may or may not also include a biopsy depending on whether you report a separate pathological examination.

You should report code 11100 for a punch biopsy because the sample is a biopsy, not a lesion that the dermatologist excised.

Bonus: The easiest way to differentiate between biopsy and excision is to ask yourself whether the dermatologist performed a test (in other words, a small sample biopsy), or whether the dermatologist removed the entire lesion.