LCD L34961: Mohs Micrographic Surgery (MMS)

Notice: It is not appropriate to bill Medicare for services that are not covered (as described by this entire LCD) as if they are covered. When billing for non-covered services, use the appropriate modifier.

Compliance with the provisions in this policy may be monitored and addressed through post payment data analysis and subsequent medical review audits.

History/Background and/or General Information

As defined by the American Medical Association Current Procedural Terminology (American Medical Association, Chicago, IL), Mohs Micrographic Surgery (MMS) is a microscope-guided tissue-sparing surgical procedure for the removal of complex or ill-defined cutaneous neoplasms of the skin and histologic examination of 100% of the surgical margins. The technique allows the Mohs surgeon to precisely define tumor margins to remove cancerous cells and leave healthy tissue intact. The procedure is performed in successive stages to remove tumor margins, as defined by the residual tumor. It is a combination of surgical excision and surgical pathology that requires a single physician to act in 2 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 Mohs surgeon removes the tumor tissue and maps and divides the tumor specimen into pieces, and each piece is embedded into an individual tissue block for histopathologic (hematoxylin-eosin or toluidine blue) examination. Thus, a tissue block in MMS is defined as an individual tissue piece embedded in a mounting medium for sectioning. 1 Mohs micrographic surgery is a two-step process: the tumor is removed in stages, followed by immediate histologic evaluation of the margins of the specimen(s). Further excision is performed until all margins are clear. The physician performing MMS furnishes both the surgical and pathological services, i.e., the excision and the histologic evaluation of the specimen(s).

MMS requires specialized equipment, tissue lab personnel and capabilities not generally present in hospital or freestanding pathology departments. Mohs surgery is usually an outpatient procedure done under local anesthesia (with or without sedation).

Covered Indications

The majority of skin cancers can be managed by excision or destruction techniques performed in an office or outpatient setting under local anesthesia and/or sedation. The medical records should clearly show that MMS 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).

After careful review, Novitas will consider reimbursement for MMS for current accepted diagnoses and indications listed in this LCD and in accordance with the 2012 Appropriate Use Criteria published by the American Academy of Dermatology (AAD-AUC) for Mohs Micrographic Surgery. 2 These criteria were compiled based on collaboration of the American Academy of Dermatology, the American College of Mohs Surgery, the American Society of Dermatologic Surgery Association and the American Society for Mohs Surgery based on evidence based medicine, clinical practice experience and expert judgment. Indications that are supported by the criteria as denoted by the CPT® codes and ICD-10-CM codes listed in the companion article Billing and Coding: Mohs Micrographic Surgery (MMS), A53883 will be considered for coverage when properly performed and the indications, procedure and findings/results are clearly and legibly documented within the beneficiary’s clinical record. Indications noted to be inappropriate by the criteria and not otherwise covered in this LCD will be denied and should NOT be billed to Medicare as MMS.

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

• Qualifications of the physician and office/facility team;

• Characteristics of the lesion pre-procedure;

• Documentation of the Medical Necessity for the Mohs micrographic technique and associated plans for the repair. (See Documentation Requirements.)

1. Qualifications of the physician and office/facility team:

While Mohs surgery is a technical method of tissue handling and processing, the training and expertise of the surgeon greatly impacts the clinical outcome. MMS is reserved for the surgeon who removes the lesion, prepares and interprets the pathology slides coincident with the resection procedure. Therefore, the physician performing the MMS must be trained and highly skilled in MMS techniques and pathology identification. The qualifications of the performing physician must be verifiable if requested by the Contractor.

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

• A Licensed Physician, enrolled as a Medicare Provider, 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. 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.

Appropriate Settings:

• 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 section. 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.

2. Characteristics of the Lesion (per-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, MMS 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.

Definitions:

• Area H: Mask areas of the 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 areas, excluding scrotum), hands, feet, nail units, ankles, nipples/areola.

• Area M: Cheeks, forehead, scalp, neck, jawline, pretibial surface.

• Area L: Trunk and extremities (excluding pretibial surfaces, hands, feet, and ankles).

• Immunocompromised: a patient with HIV/AIDS, organ transplant, hematologic malignancy or pharmacologic suppression.

• Genetic Syndromes: basal cell nevus syndrome, xeroderma pigmentosa, or other syndromes at high risk for skin cancer.

• Healthy: no immunosuppression, no prior radiation therapy to affected area, no chronic infections and no genetic syndromes that predispose to skin cancer.

• Prior Radiated Skin: patient has previously received therapeutic radiation in this area of the body.

• Aggressive features: Skin cancers having one or more of the following features have a higher incidence of local recurrence and regional metastasis such that minimal margin excision may not be in the beneficiary's best interest. The requirement for re-excision and lymph node sampling or dissection as well as extensive reconstruction may negate the benefit of minimal margin excision. Invasion of the reticular dermis and subcutaneous tissue, or origination of the lesion at this level, is associated with increased risk of regional metastasis and distant metastasis (sarcomatous lesions). These features are more commonly seen in immunocompromised individuals or arising in area of previous skin injury. Therapy aimed at definitive curative treatment is expected.

• Basal Cell Carcinoma

• Morpheaform, fibrosing, sclerosing

• Infiltrating

• Perineural

• Metatypical/Keratotic

• Micronodular

• Squamous Cell Carcinoma

• Sclerosing

• Basosquamous excluding keratotic BCC

• Small Cell

• Poorly or undifferentiated, i.e., high degree of polymorphism, high mitotic rate and/or low degree of keratinization

• Perineural or perivascular

• Spindle cell

• Pagetoid

• Infiltrating

• Keratoacanthoma (KA) type: central facial

• Single Cell

• Clear Cell

• Lymphoepithelial

• Sarcomatoid

• Breslow depth below 2mm or greater

• Clark level IV or greater

• Tissue Block: A block is the plate that tissue is placed upon, coated with embedding medium, frozen, and then placed into the microtome for cutting. Thus, a block is a plate with tissue and mounting medium on it that is placed on a single slide for reading. It may contain samples from serial levels of sampling but constitutes one block for billing purposes regardless of the number of levels (or sites) examined. It is expected that maximal efficiency will be utilized for examining serial levels of tissue.

MMS is indicated for sensitive regions of skin without redundancy, designated as H "mask areas" of the face, and includes genitalia, hands feet, nail units, ankles, and nipple/areola. Area M constitutes a region with some skin redundancy and standard excision and closure results are technically and cosmetically improved, but may result in improved functional benefits by MMS. Area L refers to the trunk and extremities excluding the regions contained in M, where standard excision technique with wound closure is not compromised by lack of skin redundancy. MMS may be appropriate for superficial lesions not requiring additional closure techniques in Area L with coverage upon redetermination.

Current Accepted Diagnoses and Indications for Mohs Micrographic Surgery; (one of three requirements for coverage)

Medicare will consider reimbursement for MMS for the following indication and anatomic locations:

I. Basal Cell Carcinoma

A. Recurrent BCC of any size or unexpected positive margin on recent excision (healthy or immunocompromised or genetic syndrome[s])

I. Aggressive Pathology - Area H, M and/or L

II. Nodular pathology - Area H, M and/or L;

III. Superficial pathology - Area H and M only

B. Primary Aggressive

I. Size less than or equal to 0.5 cm - Area H and M

II. Size greater than or equal to 0.6 cm - Area H, M and L

C. Primary Nodular BCC (healthy patient)

I. Size less than or equal to 0.5 - 1 cm - Area H and M only

II. Size 1.1 - 2 cm Area H and M only

III. Size greater than 2 cm Area H, M and L

D. Primary Nodular BCC (immunocompromised patient)

I. Size less than or equal to 0.5 cm - Area H and M only

II. Size 0.6 - 1 cm - Area H and M only

III. Size greater than or equal to 1.1 cm - Area H, M and L

E. Primary Superficial BCC (healthy patient)

I. Size less than or equal to 0.5 cm - Area H

II. Size greater than or equal to 0.6 cm - Area H and M

F. Primary Superficial BCC (immunocompromised patient)

I. Size less than or equal to 1.0 cm - Area H and M

II. Size less than 1.0 cm - Area H and M

II. Squamous Cell Carcinoma

A. Recurrent SCC of any size or unexpected positive margin on recent excision

I. Aggressive Pathology - Area H, M and L

II. Verrucous Pathology - Area H

III. KA type SCC (not central facial) - Area H, M and L

IV. In situ/Bowen - Area H and M; Non-covered Area L

V. Without aggressive histologic features, less than 2 mm depth without other defining features, Clark level less than or equal to III - Area H, M and L

B. Primary aggressive SCC (healthy patients)

I. Size - no limit Area H, M and L

C. Primary aggressive SCC (immunocompromised patients)

I. Size - no limit - Area H, M and L

D. Primary SCC without aggressive histologic features, less than 2mm depth without other defining features, Clark Level less than or equal to III (healthy patients)

N/A