This document addresses Mohs micrographic surgery (MMS), an outpatient procedure used in selective situations to treat malignant neoplasms of the skin. MMS consists of a precise tissue-sparing surgical technique to remove and process skin tissue in successive stages.

Clinical Indications

Medically Necessary:

Mohs micrographic surgery is considered medically necessary for the treatment of basal cell carcinoma, squamous cell carcinoma, melanoma in situ (Stage 0; including lentigo maligna), when the following criteria are met:

1. The lesion or tumor meets any of the following:
   1. Any of the following combinations of anatomic location and size:
      1. At least 20 mm on trunk and extremities (excluding pretibial region, hands, feet, and ankles); or
      2. At least 10 mm on scalp, neck and pretibial region; or
      3. Any size, on the face (central face, cheeks, forehead, eyelids, eyebrows, periorbital, nose, lips, chin, mandible, preauricular and postauricular skin/sulci, temple, ear), genitalia, hands or feet; OR
   2. Any of the following clinical presentations regardless of anatomic region:
      1. Deeply infiltrating lesion or difficulty estimating depth of the lesion; or
      2. Perineural invasion; or
      3. Poorly-defined borders; or
      4. Positive margins on recent excision; or
      5. Rapidly growing lesions in any anatomic area; or
      6. Recurrent lesion; OR
   3. Lesions or tumors with aggressive histologic features or at high-risk for recurrence; OR
   4. Tumors associated with a high-risk of metastasis arising in any of the following areas:
      1. Chronic fistulas, sinuses or ulcers (including sinuses of osteomyelitis); or
      2. Chronically inflamed or previously traumatized skin (such as epidermal atrophy or scars/burn scars, post-traumatic wounds, pressure sores/ulcers); or
      3. Site of prior radiation therapy; OR
   5. Individual has either of the following:
      1. Genetic syndrome (such as basal cell nevus syndrome or xeroderma pigmentosum); or
      2. Immunocompromised condition (such as hematologic malignancy, human immunodeficiency virus [HIV], organ transplantation, or pharmacologic immunosuppression).

Mohs micrographic surgery is considered medically necessary for the treatment of the following less common cutaneous tumors or lesions when the following criteria are met:

1. The lesion to be treated is known to be any of the following:
   1. Adenocystic carcinoma
   2. Adnexal carcinoma
   3. Apocrine/eccrine carcinoma
   4. Atypical fibroxanthoma
   5. Bowenoid papulosis
   6. Dermatofibrosarcoma protuberans
   7. Extramammary Paget disease
   8. Leiomyosarcoma
   9. Malignant fibrous histiocytoma/undifferentiated pleomorphic sarcoma
   10. Merkel cell carcinoma
   11. Microcystic adnexal carcinoma
   12. Mucinous carcinoma
   13. Sebaceous carcinoma

Not Medically Necessary:

Mohs micrographic surgery is considered not medically necessary when the criteria above have not been met.