**History/Background and/or General Information**

Mohs micrographic surgery (MMS) is a microscope-guided tissue-sparing surgical
procedure used for the removal of certain complex or ill-defined cutaneous
neoplasms of the skin and histologic examination of 100% of the surgical
margins. MMS uses precise measurements of tumor margins to remove cancerous
cells and leave healthy tissue intact. The procedure is performed in
successive stages to remove extensive tumors, as needed. The surgery requires
the integration of an individual functioning in two separate and distinct
capacities: surgeon and pathologist. If either of these responsibilities is
delegated to another physician or other qualified health care professional who
reports the service(s) separately, the MMS codes should not be reported.

The majority of skin cancers can be managed by excision or destruction
techniques. MMS is usually an office procedure done under local anesthesia
and/or sedation.

This LCD addresses the reasonable and necessary threshold for coverage based
on three requirements:

  1. Qualifications of the physician and office/facility team; 
  2. Characteristics of the lesion pre-procedure; 
  3. Documentation of the medical need for the Mohs micrographic technique and associated plans for the repair.

**Covered Indications**

Characteristics of the lesion pre-procedure:

The appropriate use criteria recommendations (supported by
AAD/ACMS/ASDSA/ASMS) provide a necessary starting point for consideration of
Mohs micrographic surgical treatment of a lesion. However, Mohs Micrographic
Surgery is indicated only when the superficial (lateral) or deep margins of
the cancer lesion are uncertain clinically **AND** the likelihood of surgical
cure and reconstruction would be compromised without use of immediate
microscopic examination of the surgical margins. Though complexity of the
lesion (poorly defined borders, suspected deep invasion, recurrent lesion,
prior radiation), lesion size/location, and maximum conservation of healthy
tissue are to be addressed in the preoperative medical record, the surgeon
must address why the lesion will not be (was not) managed by excision or
destruction technique.

Current accepted diagnoses and indications for Mohs Micrographic Surgery:

  1. Basal cell carcinomas (BCC), squamous cell carcinomas (SCC), basalosquamous/basosquamous cell carcinomas in anatomic locations H and M. 
    * Area H: "Mask areas" of face (central face, eyelids [including inner/outer canthi], eyebrows, nose, lips [cutaneous/mucosal/vermillion], chin, ear and periauricular skin /sulci, temple), genitalia (including perineal and perianal), hands, feet, nail units, ankles, and nipples/areola
    * Area M: Cheeks, forehead, scalp, neck, jawline, pretibial surface
  2. Basal cell carcinomas (BCC), squamous cell carcinomas (SCC), or basalosquamous/basosquamous cell carcinomas that are in anatomic locations H, M, and L (trunk and extremities) regardless of subtype, size, or depth arising in: 
    * Prior radiated skin
    * Traumatic scar
    * Area of osteomyelitis
    * Area of chronic inflammation/ulceration
    * Patients with genetic syndromes
  3. Certain recurrent skin cancers: 
    * Recurrent aggressive BCC, nodular BCC, superficial (except area L) BCC of any size, or unexpected positive margin on recent excision (healthy or immunocompromised patients with genetic syndromes)
    * Recurrent aggressive SCC, verrucous SCC, KA-type SCC (not central facial), in situ/Bowen SCC of any size or unexpected positive margin on recent excision (healthy or immunocompromised patients, or patients with genetic syndromes)
  4. Lentigo maligna, melanoma in situ, non-lentigo maligna - primary or locally recurrent in Areas H, M, L when clinical staging, work-up, and surgical treatment consistent with NCCN guidelines
  5. Less common skin cancers: 
    * Adenocystic carcinoma
    * Adnexal carcinoma
    * Angiosarcoma
    * Apocrine/eccrine carcinoma
    * Atypical Fibroxanthoma
    * Dermatofibrosarcoma protuberans
    * Extramammary Paget's Disease
    * Leiomyosarcoma
    * Malignant fibrous histiocytoma/undifferentiated pleomorphic sarcoma
    * Merkel cell carcinoma
    * Microcystic adnexal carcinoma
    * Mucinous carcinoma
    * Sebaceous carcinoma

**Limitations**

Procedures that exceed the medical need are not reasonable and necessary (not
a Medicare covered service), therefore, documentation (pre-procedure E/M note
and/or post-procedure operative notes) must address (a) why the lesion will
not be (was not) managed by standard excision or destruction technique and
(when applicable) (b) why (when utilized or referred to a plastic surgeon)
procedures for complex repair, adjacent tissue transfer or rearrangement,
flap, or graft codes are employed. Also, the options for care (both the
primary procedure options and repair options) must be discussed with the
patient and clearly noted in the pre-procedure (or post procedure as
appropriate) documentation.

The limitations listed in sections 1-5 below refer to specific body areas and
lesion characteristics. The use of Mohs Micrographic Surgery in these areas
and for these conditions is not considered medically reasonable and necessary:

  1. Both recurrent and primary actinic keratosis (AK) with focal SCC in situ; Bowenoid AK; SCC in situ (AK type) of any size in all areas in healthy or immunocompromised  
  2. Basal cell carcinoma located in Area L-- trunk and extremities (excluding pretibial surface, hands, feet, nail units, and ankles):
    * Recurrent superficial BCC (healthy or immunocompromised patients, or patients with genetic syndromes) of any size
    * Primary superficial BCC (healthy or immunocompromised patients) of any size
    * Primary nodular BCC (healthy patients)  2 cm
    * Primary nodular BCC (immunocompromised patients)  1 cm
  3. Squamous cell carcinoma located in Area L-- trunk and extremities (excluding pretibial surface, hands, feet, nail units, and ankles):
    * Primary SCC; without aggressive histologic features, <2 mm depth without other defining features, Clark level  III (healthy patients) 2 cm
    * Primary SCC keratoacanthoma (KA) type; not central facial (healthy patients)  1 cm
    * Primary in situ SCC/Bowen disease (healthy patients)  2 cm
    * Primary in situ SCC/Bowen disease (immunocompromised patients)  1 cm
  4. Desmoplastic trichoepithelioma located in Area L-- trunk and extremities (excluding pretibial surface, hands, feet, nail units, and ankles) 
  5. Bowenoid papulosis



As published in the CMS IOM Publication 100-08, _Medicare Program Integrity
Manual_ , Chapter 13, Section 13.5.4, an item or service may be covered by a
contractor LCD if it is reasonable and necessary under the Social Security Act
Section 1862 (a)(1)(A). Contractors shall determine and describe the
circumstances under which the item or service is considered reasonable and
necessary.

**Provider Qualifications  **

Qualifications of the physician and office/facility team:

Providers of Mohs surgery are limited to physicians (i.e., MD/DO) as follows:

  1. Enrolled in Medicare and a licensed physician who has completed Residency training in Dermatology or general/subspecialty surgery AND has completed additional medical training in Mohs surgery. This additional training and expertise must be verifiable. Verification of this training should be available if requested during a pre or post payment medical review. Examples of verification are letter/certificate confirming fellowship program (program certified by a nationally recognized organization); residency program with letter confirming adequate MMS training (program certified by a nationally recognized organization); credible post-graduate training course/program covering Mohs micrographic surgery technique and pathology identification; credible preceptorship with demonstrated case experience and expertise.
  2. While Mohs surgery is a technical method of tissue handling and processing, the training and expertise of the surgeon greatly impacts the clinical outcome. The surgeon must act as the pathologist for all tissue sections (reliably read the frozen section pathology) and often must function as the reconstructive surgeon.
  3. The qualified physician must provide services in the appropriate setting for the patient's medical need and condition. Success requires good tissue handling, good surgical technique, and standard of care tissue processing and staining technique. The Mohs surgery facility must meet standards of care as most are not affiliated with hospital delivery systems. A typical facility consists of procedure rooms suitable for dermatological surgery located in close proximity to a fully-equipped Mohs laboratory. The necessary equipment for Mohs cases of all complexities is available per standards of care. The Mohs laboratory typically has standard of care equipment such as cryostats, staining facilities (manual and/or automated) for standard staining of Mohs sections. There is access to appropriate immunohistochemical staining for selected Mohs cases. The setting must include a Mohs histolaboratory technician who will be either dedicated or one of a small team of biomedical staff who regularly cut Mohs sections and do sufficient numbers per week to maintain a high technical expertise in preparing Mohs sections.