Do You Know Mohs (Billing)?
Medicare Billing Guide for Mohs Micrographic Surgical (MMS):
Medicare requires the Mohs surgeon acts as both surgeon and pathologist, in order to qualify for reimbursement for the MMS procedures.
This is how the Moh’s surgeon provides both the surgical and pathology service for MMS: The physician removes the tumor in stages, and immediately performs the histologic evaluation of the margins of the specimen(s). Each subsequent tissue excision is evaluated until all margins are clear.
Providers may not bill Medicare for these procedures if preparation or interpretation of pathology slides is performed by a physician other than the Mohs surgeon.
 Only physicians (MD/DO) may perform MMS The physician performing MMS must be specifically trained and highly skilled in MMS techniques and pathologic identification If the Moh’s surgeon does not provide the histologic evaluation of the specimen(s), the CPT codes for MMS cannot be used, rather the codes (11600-11646) for the standard excision of malignant lesions should be chosen. |
Medicare will consider reimbursement for MMS for accepted diagnoses/conditions. MMS is considered medically necessary for the treatment of select skin cancers and is used to minimize wound size and scarring in critical areas such as eyes, ears, nose and lips.
Per most Medicare LCD’s, MMS is indicated for the following conditions:
1. Certain Basal Cell Carcinomas, Squamous Cell Carcinomas, or Basalosquamous Cell Carcinomas
2. Angiosarcoma of the skin
3. Keratoacanthoma, recurrent
4. Dermatofibrosarcoma protuberans
5. Malignant fibrous histiocytoma
6. Sebaceous gland carcinoma
7. Microcystic adnexal carcinoma
8. Extramammary Paget’s disease
9. Bowenoid papulosis
10. Merkel cell carcinoma
11. Bowen’s disease (squamous cell carcinoma in situ)
12. Adenoid type of squamous cell carcinoma
13. Verrucous carcinoma
14. Atypical fibroxanthoma
15. Leiomyosarcoma or other spindle cell neoplasms of the skin
16. Adenocystic carcinoma of the skin
17. Erythroplasia of Queryrat
18. Apocrine carcinoma of the skin
19. *Malignant melanoma (facial, auricular, genital and digital) when anatomical or technical difficulties do not allow conventional excision with appropriate margins
| There are a number of Local Coverage Determinations and Articles that address Mohs surgery in more detail. |
The CPT codes applicable to MMS are:
| Code | Description |
| 17311 | Mohs micrographic technique, including removal of all gross tumor, surgical excision of tissue specimens, mapping, color coding of specimens, microscopic examination of specimens by the surgeon, and histopathologic preparation including routine stain(s) (e.g.,hematoxylin and eosin, toluidine blue), head, neck, hands, feet, genitalia, or any location with surgery directly involving muscle, cartilage, bone, tendon, major nerves, or vessels; first stage, up to 5 tissue blocks. |
| 17312 | Mohs micrographic technique, including removal of all gross tumor, surgical excision of tissue specimens, mapping, color coding of specimens, microscopic examination of specimens by the surgeon, and histopathologic preparation including routine stain(s) (e.g.,hematoxylin and eosin, toluidine blue), head, neck, hands, feet, genitalia, or any location with surgery directly involving muscle, cartilage, bone, tendon, major nerves, or vessels; each additional stage after the first stage, up to 5 tissue blocks (list separately in addition to code for primary procedure). |
| 17313 | Mohs micrographic technique, including removal of all gross tumor, surgical excision of tissue specimens, mapping, color coding of specimens, microscopic examination of specimens by the surgeon, and histopathologic preparation including routine stain(s) (e.g., hematoxylin and eosin, toluidine blue), of the trunk, arms, or legs; first stage, up to 5 tissue blocks. |
| 17314 | Mohs micrographic technique, including removal of all gross tumor, surgical excision of tissue specimens, mapping, color coding of specimens, microscopic examination of specimens by the surgeon, and histopathologic preparation including routine stain(s) (e.g., hematoxylin and eosin, toluidine blue), of the trunk, arms, or legs; each additional stage after the first stage, up to 5 tissue blocks (list separately in addition to code for primary procedure). |
| 17315 | Mohs micrographic technique, including removal of all gross tumor, surgical excision of tissue specimens,mapping, color coding of specimens, microscopic examination of specimens by the surgeon, and histopathologic preparation including routine stain(s) (e.g., hematoxylin and eosin, toluidine blue), each additional block after the first 5 tissue blocks, any stage (list separately in addition to code for primary procedure). |
As in billing of all medical procedures, medical necessity and documentation are essential to proper claims reimbursement. Key points to remember for documenting MMS are:
1. show that this procedure was chosen because of: the complexity (e.g. poorly defined clinical borders, possible deep invasion, prior irradiation, size or location (e.g. maximum conservation of tumor -free tissue is important)
2. describe for the initial stage the histology of the specimens taken including: depth of invasion, pathological pattern, cell morphology, and any applicable perineural invasion or scar tissue
3. describe for each subsequent stage: the tumor pathological pattern and cell morphology as in the initial stage or any changes if applicable
This special edition article published by CMS, lists specific guidance for billing MMS services provided Medicare beneficiaries. Here is the link to the full MLN Matters® article SE1318.
If you have any questions, please contact your Medicare contractor at their toll-free number, which may be found here on the CMS website.