CPT Coding for Uncertain Skin Lesion Requiring Pathology
When you are uncertain whether a lesion is a benign skin tag and need pathological confirmation, you must code it as an excision rather than a simple skin tag removal, using CPT codes 11400-11446 (excision of benign lesion) or 11600-11646 (excision of malignant lesion) based on final pathology, with code selection determined by the lesion size plus margins and anatomic location.
Coding Algorithm for Uncertain Lesions
When Pathology is Required
Complete excisional biopsy is the appropriate procedure when diagnosis is uncertain, as this allows full histopathological examination of the entire lesion for accurate diagnosis and staging 1, 2.
The excision should include a 2mm margin of normal skin and extend through the full thickness of the dermis with a cuff of subcutaneous fat 1, 3.
Measure the lesion diameter plus the narrowest margin prior to excision - this combined measurement determines your CPT code selection 4.
CPT Code Selection Process
Use excision codes (11400-11446 for benign, 11600-11646 for malignant) rather than destruction or simple removal codes when sending tissue to pathology 4.
Code selection is based on:
Only the definitive, most complex procedure may be billed - if you attempt a simpler removal first then immediately proceed to excision, only code the excision 4.
Critical Documentation Requirements
Your operative note must include specific elements to support accurate coding:
Pre-excision measurements: Document the lesion's greatest clinical diameter plus the margin width you plan to excise 4
Clinical description: Record appearance, size, exact anatomic location, and your differential diagnosis including why you're uncertain it's a benign skin tag 1
Pathology form details: Provide complete clinical history, relevant previous history, anatomic site, and differential diagnosis to the pathologist 3, 1
Excision technique: Document that you performed full-thickness excision through the dermis with subcutaneous fat 1
Common Coding Pitfalls to Avoid
Never code as simple skin tag removal (11200-11201) when sending to pathology - these codes are for destruction/removal of clearly benign lesions not requiring histological examination 4.
Do not use shave biopsy codes if you performed full excision - shave biopsies should be avoided when melanoma or other serious pathology needs exclusion, as they prevent accurate staging 3, 1.
Avoid coding before receiving final pathology - the distinction between benign (11400 series) and malignant (11600 series) codes depends on the pathologist's diagnosis 4.
Do not bill separately for simple closure - this is included in the excision code 4.
When Uncertainty Exists
If clinical examination cannot definitively confirm a benign skin tag, complete excisional biopsy is medically necessary to exclude melanoma, squamous cell carcinoma, or other malignancies that may occasionally present in pedunculated lesions 5.
Partial sampling techniques (punch biopsy, shave biopsy) should not be used when there is diagnostic uncertainty, as they risk sampling error and prevent accurate pathological staging 3, 1, 2.