Dermatology billing services have to get three things right: the biopsy code that matches the technique (tangential, punch or incisional), destruction and excision codes counted and sized exactly as CPT defines them, and modifier 59 or XS only when a biopsy and a removal are on separate lesions. Modifier 59 without separate-lesion documentation is the error to prevent.
A dermatology clinic can bill a dozen lines on one visit: biopsies, destructions, an excision, a repair and pathology. Each of those lines has its own counting rule, and Medicare’s NCCI edits bundle many of them together unless the documentation proves they were separate. This primer covers the codes that matter and where the claims break.
Biopsy codes follow the technique
Since CPT 2019, skin biopsy codes are chosen by technique. AAPC’s Otolaryngology Coding Alert (12 February 2019) gives the descriptors:
- 11102: Tangential biopsy of skin (eg, shave, scoop, saucerize, curette); single lesion. 11103: each separate/additional lesion.
- 11104: Punch biopsy of skin (including simple closure, when performed); single lesion. 11105: each separate/additional lesion.
- 11106: Incisional biopsy of skin (eg, wedge) (including simple closure, when performed); single lesion. 11107: each separate/additional lesion.
When more than one technique is used at one encounter, AAPC’s Knowledge Center (2 June 2025) says only one primary biopsy code is reported, the one for the most invasive technique performed, with the other biopsies reported using the matching add-on codes. One punch biopsy and two tangential biopsies are reported as 11104 once and 11103 twice, not 11102 plus 11104.
The note has to name the technique. “Biopsy taken” without shave, punch or wedge cannot be coded to the right family, and simple closure is already included in the punch and incisional codes.
Destruction: premalignant versus benign, counted differently
AAPC’s General Surgery Coding Alert (4 January 2007) sets out the destruction codes and how they are counted:
- 17000: destruction, premalignant lesions (eg, actinic keratoses); first lesion.
- 17003: second through 14 lesions, each.
- 17004: 15 or more lesions, reported alone. The same article says 17004 is never reported with 17000 or 17003 for the same session.
- 17110: destruction of benign lesions other than skin tags or cutaneous vascular lesions; up to 14 lesions.
- 17111: 15 or more lesions. 17110 and 17111 are never billed together.
So 13 actinic keratoses are 17000 plus 12 units of 17003, while five benign lesions are one line of 17110. Applying the premalignant counting method to benign lesions, or the reverse, is an easy error to make. The diagnosis has to match the family: the premalignant codes are for lesions such as actinic keratoses.
CMS’s RVU26D file (released 26 August 2026) assigns 17000, 17004, 17110 and 17111 a 10-day global period, while the primary biopsy codes 11102, 11104 and 11106 carry a zero-day global. Follow-up visits inside a destruction’s 10-day window need to be checked against Medicare’s global surgery rules before they are billed.
Excisions are sized, and the size includes margins
Excision codes are split by benign or malignant, by anatomic site and by excised diameter. AAPC’s Revenue Cycle Insider (31 August 2026) gives the CPT definition: the greatest clinical diameter of the lesion plus the narrowest margins required for complete excision, calculated as lesion diameter plus twice the narrowest margin. It uses the example of a 2.0 cm neck melanoma with 0.5 cm margins, an excised diameter of 3.0 cm, reported as 11623, excision, malignant lesion including margins, scalp, neck, hands, feet, genitalia; excised diameter 2.1 to 3.0 cm.
On the trunk, arms or legs, a malignant excision of 1.1 to 2.0 cm is 11602 (AAPC General Surgery Coding Alert, 30 January 2025). Two documentation rules follow: the lesion and margins have to be measured and recorded before excision, and the benign or malignant code family follows the pathology, so excision claims should not go out until the path report is back.
Modifier 59 and XS: separate lesions only
CMS’s NCCI Policy Manual, Chapter III (revision date 1 January 2026), sets three rules that govern multi-line dermatology claims:
- Only one removal code per lesion. If a lesion is removed by one method, only one removal code may be reported, and a procedure converted to another method is reported as the completed method (Section E.1).
- A biopsy of the lesion you then remove is included. The lesion removal codes include procuring tissue from the same lesion by biopsy at the same encounter. The biopsy codes may be reported separately only when the biopsy is of a different lesion (Section E.2).
- Biopsy plus destruction. Section L, paragraph 14, says the edits pairing 11102, 11104 and 11106 with 17000 and 17004 are often bypassed using 59, XE or XS, and that this is appropriate only when the two procedures were on separate lesions or at separate encounters.
CMS’s MLN booklet on modifiers 59, XE, XP, XS and XU (MLN1783722, April 2026) adds that XS and the other X modifiers should be used instead of 59 whenever possible, that a different diagnosis alone is not enough to support the modifier, and that the documentation must show the separate site or lesion. Its worked example pairs 11102 with 17000: if the two lesions are on different sides of the body, use anatomic modifiers such as RT and LT rather than 59 or XS. For a dermatology note, each lesion needs its own location, description and procedure.
Pathology: 88304 or 88305, per specimen
AAPC’s 31 August 2026 guidance assigns skin cysts, debridement specimens and skin tags to 88304 (Level III surgical pathology, gross and microscopic examination), and all other skin specimens, such as a melanoma excision, to 88305 (Level IV). CMS’s Chapter III (Section E.4) says that if multiple lesions are submitted as a single specimen, only one pathology code may be reported, but a separate code may be reported for each lesion that is medically necessary to submit separately with its precise location. Separate containers and labels on the requisition are what support separate 88305 lines. Our pathology billing guide covers the lab side.
Questions to ask a dermatology billing partner
- Do you audit biopsy technique and lesion counts against the note before every claim?
- When do you use XS rather than 59, and what documentation do you require first?
- Do you hold excision claims for pathology and check the recorded pre-excision size?
- How do you track destruction global periods for follow-up visits?
Coding quick-references are in the AMS resources library. When biopsy, destruction and modifier edits are where your claims keep failing, that is the work our in-house global team, US-led, has handled for practices since 1992 as part of our dermatology billing services.
