Maximize reimbursement, eliminate denials, and ensure full compliance with precise coding for biopsies and excisions. Most dermatology practices lose 12–22% of collectible revenue in these two code families alone.
Estimated average annual revenue leakage from biopsy and excision coding errors in a 2–3 physician derm practice.
Biopsy and excision CPT codes represent the highest volume — and the highest error rate — of any code family in dermatology billing. Between the 2019 CPT biopsy code restructure (11102–11107), the excision range spanning benign and malignant lesions, modifier complexity, and payer-specific LCD policies, these codes are where most derm practices silently hemorrhage revenue.
The stakes are high in both directions: underbilling leaves your money on the table, while overbilling or incorrect documentation creates audit exposure that can result in extrapolated recoupment demands — meaning one bad claim pattern can cost you tens of thousands in recovery.
The 2019 CPT biopsy restructure replaced the single code 11100/11101 with a family of six codes (11102–11107) differentiated by technique. Practices that weren't updated — or weren't trained — are still coding this wrong in 2026.
Incorrect technique classification, missed additional-lesion codes, and wrong size thresholds collectively drain more revenue than any other coding area in derm.
Medicare MACs and commercial payers have aggressive LCD policies for biopsy and excision. Missing a modifier, misclassifying the lesion type, or submitting without proper documentation triggers automatic denial.
Biopsy and excision codes are among the most audited in dermatology. RAC auditors specifically target high-volume procedure patterns in derm practices without robust documentation standards.
Since 2019, biopsy CPT code selection is technique-driven — not site-driven. The wrong technique classification is the single most common biopsy billing error. Here is the complete framework.
Using 11100/11101 (old codes) after 2019. These codes are invalid. Payers will deny on sight. Yet practices still use them years after the change — usually because their EHR templates were never updated. We audit this in every new client onboarding.
Coding all biopsies as 11104 (punch) regardless of technique. If the clinician used a blade tangentially and you bill 11104, that's upcoding — audit exposure. If they used a punch and you bill 11102, that's underbilling. Technique must match the operative note.
Missing add-on codes for multiple lesions. If a patient has 3 punch biopsies, you should bill 11104 + 11105 + 11105. Billing only 11104 × 3 as separate claims is incorrect. Billing only 11104 once loses two procedures entirely.
Incorrect modifier usage on same-day E&M. When a biopsy is performed at the same visit as a significant, separately identifiable E&M, Modifier 25 is required on the E&M. Missing it causes E&M denial. Adding it incorrectly triggers audit scrutiny.
A biopsy removes tissue for diagnostic purposes — partial or complete removal with diagnostic intent. An excision removes a lesion with the intent to treat (complete removal with adequate margins). If a shave biopsy completely removes the lesion and pathology confirms it, this is still a biopsy (11102) — not an excision. Upcoding to an excision code is a frequent audit trigger.
Excision codes are size-driven and pathology-driven. The correct code depends on the excised diameter (including margins), the anatomical site, and whether the lesion is benign or malignant. Errors here are systematic — and expensive.
The excision diameter used for CPT code selection is not the lesion size. It is the lesion size plus the surgical margins taken in all directions — the full excised specimen diameter as measured at the time of surgery, before any tissue contraction.
Coding to lesion size instead of excised diameter. This is the single most prevalent excision billing error. A practice doing 15 excisions/day at an average underbill of $90 loses $337,500 per year from this one mistake alone.
Wrong site category. Coding a nasal tip BCC as 11602 (trunk/arm range) instead of 11642 (face/nose/lip malignant) is an ~$180 underbill per claim. Payers won't reject it — they'll just pay the lower amount. You'll never know unless you audit.
Each denial reason below represents a systematic, fixable problem — not a one-off error. If you're seeing these patterns, the issue is in your coding workflow, not just individual claims.
The operative note is your entire defense in an audit. A payer cannot deny a correctly documented claim. Every element below must appear in the note — not as an afterthought, but as a structured, auditable record.
RAC and UPIC auditors use statistical sampling — they audit a small sample of claims, identify an error rate, and extrapolate that rate across your entire billing history. One documentation gap found in 5 of 20 sampled claims can result in a demand to repay 25% of all excision reimbursement going back 3 years. That is why documentation isn't just compliance — it's financial protection.
These aren't hypothetical scenarios. These are the three most common revenue-loss patterns we find when auditing a new dermatology client's billing history.
Generic billing vendors learn your specialty on your dime. We built Master Billing exclusively for dermatology — every workflow, every coder, and every payer rule is built for derm from day one.
Exclusive dermatology focus means deep pattern recognition across every biopsy and excision scenario.
Industry average is 85%. Our derm-specific scrubbing rules catch errors before claims leave the practice.
Faster payment cycles through correct first-pass coding — no rework, no holds, no appeals required.
Every coder on your account is credentialed and derm-specialized. No generalists touching your claims.
We'll audit 90 days of your biopsy and excision claims, identify every systematic error, and tell you exactly what your practice is losing — and how to fix it. Free, within 5 business days, no commitment required.
No sales pressure. No commitment. Just a clear picture of where your revenue is going.
Fill out your practice details and we’ll send you the free 14-point Revenue Leak Audit Checklist — plus a complimentary diagnostic within 1 business day.
📫 Checklist delivered by email · 100% HIPAA Compliant · No commitment
