Summary & Overview
CPT 11604: Excision of Malignant Skin Lesion, Trunk/Arms/Legs, 3.1-4.0 cm
CPT code 11604 represents the excision of a malignant skin lesion, including margins, on the trunk, arms, or legs, with a diameter between 3.1 cm and 4.0 cm. This procedure is a critical component in the management of skin cancers, particularly melanoma, and is frequently performed in both office and hospital outpatient settings. Nationally, this code is recognized by major payers including Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare, making it relevant for a wide range of providers and patients.
This publication provides a comprehensive overview of 11604, covering payer coverage, clinical context, and related coding benchmarks. Readers will gain insight into policy updates, typical sites of service, and the role of this code in dermatology and procedural skin surgery. The summary also highlights associated modifiers and taxonomies, as well as relevant ICD-10 diagnoses and related CPT codes, offering a clear understanding of how 11604 fits within broader billing and clinical workflows. The information is designed to support healthcare professionals, administrators, and policy analysts in navigating the complexities of medical billing and coding for malignant skin lesion excision.
CPT Code Overview
CPT code 11604 is used to report the excision of a malignant skin lesion, including margins, on the trunk, arms, or legs, where the excised diameter measures between 3.1 cm and 4.0 cm. This procedure falls under the category of surgical procedures on the skin and is commonly performed in an office setting (Place of Service 11) or in a hospital outpatient facility (Place of Service 19 or 22). The code is integral for documenting and billing the removal of skin cancers in these anatomical regions, ensuring accurate representation of the clinical service provided.
Clinical & Coding Specifications
Clinical Context
A patient presents to a dermatology clinic with a suspicious skin lesion on the trunk, arm, or leg. After clinical evaluation and possible biopsy, the lesion is diagnosed as malignant, such as malignant melanoma. The provider determines that surgical excision is necessary, and the lesion measures between 3.1 cm and 4.0 cm in diameter, including margins. The procedure is performed in an office or hospital outpatient setting. The excision is documented, and the specimen is sent for pathology. Post-procedure, wound closure may be performed, and follow-up is scheduled to monitor healing and recurrence.
Coding Specifications
-
Modifier
59: Distinct Procedural Service. Used when a procedure or service is distinct or independent from other services performed on the same day. -
Modifier
51: Multiple Procedures. Used when multiple procedures are performed during the same session by the same provider.
| Modifier Code | Description |
|---|---|
59 | Distinct Procedural Service |
51 | Multiple Procedures |
- Provider Taxonomies:
| Taxonomy Code | Specialty Name |
|---|---|
207N00000X | Dermatology |
207ND0101X | MOHS-Micrographic Surgery |
207NS0135X | Procedural Dermatology |
Related Diagnoses
-
C43.51: Malignant melanoma of anal skin- Indicates a malignant melanoma located on the anal skin, relevant for excision procedures on the trunk.
-
C43.52: Malignant melanoma of skin of breast- Represents malignant melanoma on the breast skin, applicable for excision on the trunk.
-
C43.59: Malignant melanoma of other part of trunk- Covers malignant melanoma on other trunk areas, directly relevant to excision procedures coded as
11604.
- Covers malignant melanoma on other trunk areas, directly relevant to excision procedures coded as
-
C43.60: Malignant melanoma of unspecified upper limb, including shoulder- Refers to malignant melanoma on the upper limb or shoulder, relevant for excision procedures on arms or legs as described by
11604.
- Refers to malignant melanoma on the upper limb or shoulder, relevant for excision procedures on arms or legs as described by
Related CPT Codes
-
11603: Excision, malignant lesion, face, ears, eyelids, nose, lips; excised diameter 2.1 to 3.0 cm.- Used for excision of malignant lesions on the face or other specified areas, with a smaller excised diameter than
11604.
- Used for excision of malignant lesions on the face or other specified areas, with a smaller excised diameter than
-
11605: Excision, malignant lesion, face, ears, eyelids, nose, lips; excised diameter 4.1 to 5.0 cm.- Used for excision of larger malignant lesions on the face or other specified areas.
-
12051: Layer closure of wounds of face, ears, eyelids, nose, lips; 2.5 cm or less.- Commonly used for wound closure after excision procedures, especially when layered closure is required.
-
13131: Repair, complex, forehead, cheeks, chin, mouth, neck, axillae, genitalia, hands and/or feet; 1.1 to 2.5 cm.- Used for complex repair of wounds in specified areas, which may be necessary after excision of malignant lesions.
Clinical Workflow Relation:
12051and13131are often used in conjunction with excision codes like11604when wound closure is performed.11603and11605are alternative excision codes based on lesion size and location.
National Reimbursement Benchmarks
Medicare's national mean rate for CPT code 11604 is $321.29, which is lower than the BUCA (Blue Cross Blue Shield, UnitedHealth Group, Cigna, Aetna) average commercial mean rate of $333.49. Among commercial payers, UnitedHealth Group has the highest mean rate at $468.33, while Aetna is the lowest at $248.68.
Rate dispersion, measured by the difference between the 75th and 25th percentiles, varies significantly across payers. Medicare shows the tightest range at $31.00, indicating relatively consistent rates nationally. In contrast, UnitedHealth Group exhibits the widest range at $285.33, reflecting substantial variability in commercial reimbursement. Cigna and BUCA also display broad ranges, while Aetna and Blue Cross Blue Shield are more moderate.
The table and chart below present a detailed breakdown of national benchmarks for each payer, including mean rates and percentile values.
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