Part B Insider (Multispecialty) Coding Alert

Lesion Coding:

Look Past the Urban Myth About Adding up Lesion Sizes

Pay attention to your non-Medicare carriers' policies on multiple lesions

Myth: When your doctor excises multiple lesions, you should add their areas together and bill for one excision.

Fact: This is a "common misconception," according to CPT Assistant. In fact, you should bill for each lesion separately, using the 59 modifier. The only exception is if the doctor excises two lesions close together, using only one excision.

Some coders, especially those who don't do integumentary coding very often, become confused because the rules are different for laceration repairs. With laceration repairs, you do add the lengths of tissue repaired and bill one code.

With lesion excision, you should calculate the size of the excision by measuring the size of the lesion plus the size of the margins necessary to ensure a clean margin.

Why? The descriptors for 11300-11313 specify "single lesion," which means that you may report one code for each lesion that the doctor removes using shave technique. If, for instance, the physician shaves 16 dermal lesions, you may report an appropriate code for each shaving. Keep in mind, however, that if the physician does shave an extraordinary number of lesions during a single session, you may have to submit documentation to explain the situation.

Example: Your surgeon removes, by shaving, four dermal lesions: one on the left upper arm, measuring 1.0 cm, two on the chest, measuring 1.4 cm and 1.6 cm, and another on the neck, measuring 0.4 cm.

In this case, you would report 11301 (Shaving of epidermal or dermal lesion, single lesion, trunk, arms or legs; lesion diameter 0.6 to 1.0 cm) for the upper arm lesion, two units of 11302 (... lesion diameter 1.1 to 2.0 cm) to describe shaving of the chest lesions, and one unit of 11305 (Shaving of epidermal or dermal lesion, single lesion, scalp, neck, hands, feet, genitalia; lesion diameter 0.5 cm or less).

Payer differences: Some payers might prefer that you list each removal as a separate line item, with modifier 59 (Distinct procedural service) appended to the second and subsequent identical codes. In the example, this means you would report 11301, 11302, 11302-59, and 11305. Keep in mind that some payers may also require modifier 51 (Multiple procedures), and apply a multiple-procedure discount as well, on claims involving multi-lesion shaving.