Summary & Overview

CPT 17315: Mohs Micrographic Surgery for Malignant Skin Lesions

CPT code 17315 represents Mohs micrographic surgery, a staged surgical procedure that removes malignant skin lesions with immediate histologic margin evaluation to ensure complete excision while preserving healthy tissue. Nationally, Mohs surgery is a key treatment for certain high-risk cutaneous malignancies because it combines high cure rates with tissue-sparing techniques, impacting surgical oncology, dermatology practice patterns, and facility utilization.

Major payers included in this analysis are Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find an overview of clinical context for Mohs surgery, typical sites of service, and payer coverage considerations. The publication summarizes common billing and coding elements tied to CPT code 17315, presents benchmark reimbursement perspectives where available, and highlights relevant policy and utilization issues affecting access to Mohs procedures.

The report is designed to inform clinicians, coding professionals, and policy analysts about the clinical rationale for the service, how payers approach coverage and claims processing for Mohs surgery, and areas where coding clarity or policy updates influence billing and site-of-service decisions. Data not available in the input are indicated where applicable.

AetnaBlue Cross Blue ShieldCigna HealthUnitedHealthcareMedicare17315CPTMohs surgerydermatologic surgerysurgical oncologyoutpatient surgeryfrozen sectionmargin control

Billing Code Overview

CPT code 17315 describes Mohs micrographic surgery, a multistaged technique for excising malignant skin lesions layer by layer with immediate histopathological assessment to confirm negative margins. The method is performed to maximize tissue conservation while ensuring complete tumor removal.

Service type: Surgical excision with intraoperative histopathologic margin control
Typical site of service: Ambulatory surgical center or hospital outpatient setting; may also be performed in dermatology or surgical clinic procedure suites equipped for frozen-section pathology

Clinical & Coding Specifications

Clinical Context

A 68-year-old patient presents to a dermatologic surgery clinic with a biopsy-proven basal cell carcinoma of the nasal tip. The lesion is clinically well-defined but located in a cosmetically sensitive area. After preoperative evaluation and informed consent, the patient undergoes 17315 Mohs micrographic surgery. The procedure is staged: the physician excises the visible tumor with minimal margins, maps and submits the tissue for immediate frozen-section histopathologic assessment, and returns to the operative field to remove additional tissue only where residual tumor is identified. This cycle continues until margins are clear. The clinical workflow includes preoperative marking, local anesthesia administration, staged excision with specimen orientation and mapping, frozen-section pathology processing and microscopic margin evaluation, subsequent additional stages if required, and final reconstruction or referral for wound repair once negative margins are confirmed. Typical site of service is an ambulatory surgery center or hospital outpatient department, and the service type is surgical dermatologic procedure with intraoperative pathology interpretation and staged excision.

Coding Specifications

Modifier	Description	When to Use
`11`	Anesthesia start time	When reporting anesthesia time on the claim for concurrent anesthesia services (used with appropriate anesthesia reporting processes).
`22`	Increased procedural services	When the procedure requires substantially greater work or time than typical for `17315` (documented justification required).
`23`	Unusual anesthesia	When general anesthesia or monitored anesthesia care was required for a procedure normally performed under local anesthesia.
`52`	Reduced services	When a planned `17315` Mohs stage is partially reduced or not completed as originally intended.
`53`	Discontinued procedure	When `17315` is started but discontinued due to extenuating circumstances or complications.
`59`	Distinct procedural service	When another distinct procedure is performed the same day and not typically included in `17315` (use to indicate separate anatomic site or distinct service).
`62`	Two surgeons	When two surgeons work together as co-surgeons during the Mohs procedure and documentation supports co-surgeon involvement.
`76`	Repeat procedure by same physician	When a repeat Mohs procedure on the same lesion/site is performed by the same physician during the postoperative period.
`77`	Repeat procedure by another physician	When a repeat Mohs procedure on the same lesion/site is performed by a different physician (modifier `77` may be applied if payer accepts).
`79`	Unrelated procedure or service by same physician during the postoperative period	When a separate, unrelated surgical procedure is performed during the global period for `17315`.

Taxonomy Code	Specialty	Notes
`207N00000X`	Dermatology	Physicians who commonly perform Mohs surgery, including dermatologic surgeons.
`2080P0207X`	Otolaryngology - Head & Neck Surgery	Specialists who may perform Mohs on facial/anatomic sites and manage reconstruction.
`207L00000X`	Plastic Surgery	Surgeons who commonly perform complex reconstruction after Mohs excision.
`363L00000X`	Pathology	Pathologists or dermatopathologists involved in frozen-section interpretation or oversight.

Related Diagnoses

ICD-10 Code	Description	Clinical Relevance
`C44.219`	Basal cell carcinoma of skin of other part of face	A common malignant lesion treated with Mohs surgery for margin control on facial sites.
`C44.311`	Squamous cell carcinoma of skin of right eyelid, including canthus	Squamous cell carcinoma in critical anatomic areas often managed with Mohs to preserve function and ensure clear margins.
`C44.312`	Squamous cell carcinoma of skin of left eyelid, including canthus	Same clinical relevance for left-sided periocular lesions.
`C44.509`	Unspecified malignant neoplasm of skin of trunk, unspecified	Represents trunk lesions where Mohs may be indicated for high-risk or recurrent tumors.
`D04.9`	Carcinoma in situ of skin, unspecified	In situ lesions that are sometimes treated with Mohs when tissue-sparing margin control is desired.
`C44.91`	Malignant neoplasm of skin, unspecified, site unspecified	Used when a skin malignancy is documented without a more specific site; Mohs may be considered based on pathology and site risk.

Related CPT Codes

CPT Code	Description	Relationship to This Procedure
`11102`	Tangential biopsy of skin (e.g., shave, scoop), single lesion	Commonly performed prior to Mohs to establish diagnosis guiding the need for `17315`.
`11100`	Biopsy of single lesion, punch	Alternative diagnostic biopsy performed before planning Mohs surgery.
`12002`	Simple repair of superficial wounds (e.g., for wounds on the face, ears, eyelids, nose, lips), 2.5 cm or less	May be used for primary closure after final stage of `17315` when simple closure is feasible.
`14040`	Adjacent tissue transfer or rearrangement, forehead, cheeks, chin, mouth, neck; defect 10.1 cm to 30.0 cm	Example of complex reconstruction codes that may follow `17315` when extensive tissue rearrangement is required.
`88331`	Pathology; frozen section single specimen	Represents the immediate intraoperative frozen-section interpretation associated with Mohs stages when separately reported and payable by the payer.

Beta

OpenPayer Beta

Summary & Overview

CPT 17315: Mohs Micrographic Surgery for Malignant Skin Lesions

AetnaBlue Cross Blue ShieldCigna HealthUnitedHealthcareMedicare17315CPTMohs surgerydermatologic surgerysurgical oncologyoutpatient surgeryfrozen sectionmargin control

Billing Code Overview

Service type: Surgical excision with intraoperative histopathologic margin control
Typical site of service: Ambulatory surgical center or hospital outpatient setting; may also be performed in dermatology or surgical clinic procedure suites equipped for frozen-section pathology

Clinical & Coding Specifications

Clinical Context

Coding Specifications

Modifier	Description	When to Use
`11`	Anesthesia start time	When reporting anesthesia time on the claim for concurrent anesthesia services (used with appropriate anesthesia reporting processes).
`22`	Increased procedural services	When the procedure requires substantially greater work or time than typical for `17315` (documented justification required).
`23`	Unusual anesthesia	When general anesthesia or monitored anesthesia care was required for a procedure normally performed under local anesthesia.
`52`	Reduced services	When a planned `17315` Mohs stage is partially reduced or not completed as originally intended.
`53`	Discontinued procedure	When `17315` is started but discontinued due to extenuating circumstances or complications.
`59`	Distinct procedural service	When another distinct procedure is performed the same day and not typically included in `17315` (use to indicate separate anatomic site or distinct service).
`62`	Two surgeons	When two surgeons work together as co-surgeons during the Mohs procedure and documentation supports co-surgeon involvement.
`76`	Repeat procedure by same physician	When a repeat Mohs procedure on the same lesion/site is performed by the same physician during the postoperative period.
`77`	Repeat procedure by another physician	When a repeat Mohs procedure on the same lesion/site is performed by a different physician (modifier `77` may be applied if payer accepts).
`79`	Unrelated procedure or service by same physician during the postoperative period	When a separate, unrelated surgical procedure is performed during the global period for `17315`.

Taxonomy Code	Specialty	Notes
`207N00000X`	Dermatology	Physicians who commonly perform Mohs surgery, including dermatologic surgeons.
`2080P0207X`	Otolaryngology - Head & Neck Surgery	Specialists who may perform Mohs on facial/anatomic sites and manage reconstruction.
`207L00000X`	Plastic Surgery	Surgeons who commonly perform complex reconstruction after Mohs excision.
`363L00000X`	Pathology	Pathologists or dermatopathologists involved in frozen-section interpretation or oversight.

Related Diagnoses

ICD-10 Code	Description	Clinical Relevance
`C44.219`	Basal cell carcinoma of skin of other part of face	A common malignant lesion treated with Mohs surgery for margin control on facial sites.
`C44.311`	Squamous cell carcinoma of skin of right eyelid, including canthus	Squamous cell carcinoma in critical anatomic areas often managed with Mohs to preserve function and ensure clear margins.
`C44.312`	Squamous cell carcinoma of skin of left eyelid, including canthus	Same clinical relevance for left-sided periocular lesions.
`C44.509`	Unspecified malignant neoplasm of skin of trunk, unspecified	Represents trunk lesions where Mohs may be indicated for high-risk or recurrent tumors.
`D04.9`	Carcinoma in situ of skin, unspecified	In situ lesions that are sometimes treated with Mohs when tissue-sparing margin control is desired.
`C44.91`	Malignant neoplasm of skin, unspecified, site unspecified	Used when a skin malignancy is documented without a more specific site; Mohs may be considered based on pathology and site risk.

Related CPT Codes

CPT Code	Description	Relationship to This Procedure
`11102`	Tangential biopsy of skin (e.g., shave, scoop), single lesion	Commonly performed prior to Mohs to establish diagnosis guiding the need for `17315`.
`11100`	Biopsy of single lesion, punch	Alternative diagnostic biopsy performed before planning Mohs surgery.
`12002`	Simple repair of superficial wounds (e.g., for wounds on the face, ears, eyelids, nose, lips), 2.5 cm or less	May be used for primary closure after final stage of `17315` when simple closure is feasible.
`14040`	Adjacent tissue transfer or rearrangement, forehead, cheeks, chin, mouth, neck; defect 10.1 cm to 30.0 cm	Example of complex reconstruction codes that may follow `17315` when extensive tissue rearrangement is required.
`88331`	Pathology; frozen section single specimen	Represents the immediate intraoperative frozen-section interpretation associated with Mohs stages when separately reported and payable by the payer.