Mohs Micrographic Surgery

Title XVIII of the Social Security Act (SSA)

• Title XVIII of the Social Security Act, §1861[s] [1], only physicians (MD/DO) may perform this procedure.
• Title XVIII of the Social Security Act, §1862(a)(1)(A) states that no Medicare payment shall be made for items or services which are not reasonable and necessary for the diagnosis or treatment of illness or injury.
• Title XVIII of the Social Security Act, Section §1833(e), this section prohibits Medicare payment for any claim which lacks the necessary information to process the claim.

CMS Publications

• CMS Pub. 100-02, Medicare Benefit Policy Manual, Chapter 15 – Covered Medical and Other Health Services, §30 - Physician Services.
• CMS Pub. 100-02, Medicare Benefit Policy Manual, Chapter 16 – General Exclusions From Coverage, §120 - Cosmetic Surgery.
• CMS Pub. 100-04, Medicare Claims Processing Manual, Chapter 12 – Physicians/Nonphysician Practitioners, §40-40.6, Surgeons and Global Surgery.
• CMS Pub. 100-04, Medicare Claims Processing Manual, Chapter 12 – Physicians/Nonphysician Practitioners, §60, Payment for Pathology Services.
• CMS Transmittal No. 434, Pub. 100-04, Medicare Claims Processing Manual, Change Request #3458, January 14, 2005, Addition of CLIA Edits to Certain Health Care Procedure Coding System (HCPCS) Codes for Mohs Surgery.
• CMS Transmittal No, 857, effective date October 3, 2018 Change Request 10901 Local Coverage Determinations (LCDs) Implementation date January 8, 2019.

As defined by the American Medical Association Current Procedural Terminology (American Medical Association, Chicago, IL), Mohs Micrographic Surgery (MMS) is a technique for the removal of complex or ill-defined skin cancer with histologic examination of 100% of the surgical margins. It requires the integration of an individual functioning 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 services separately, these 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 examination.

Mohs micrographic surgery is a 2-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.
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 (See Sections 1861 [s] [2] and 1862 [a] [140 of Title XVIII of the Social Security Act; 42 CFR, Sections 410.74, 410.75, 410.76 and 419.22; 58 FR 18543, April 7, 2000.).

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.

This LCD addresses the reasonable and necessary threshold for coverage based on 3 requirements;

1. Qualifications of the physician and office/facility team;
2. Characteristics of the lesion pre-procedure;
3. Documentation of the Medical Necessity for the MOHS micrographic technique and associated plans for the repair. See Documentation Requirements in associated A57477 Billing and Coding Article: Mohs Micrographic Surgery.

Indications:
Coverage for Mohs Micrographic Surgery, in accordance with the 2012 Appropriate Use Criteria (AUC) for Mohs Micrographic Surgery as published in the Journal of the American Academy of Dermatology Volume 67, Issue 4, pp 531-550, October 2012, was carefully reviewed. 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.

The majority of simple skin cancers can be managed by simple excision or destruction techniques. The medical records should clearly show that Mohs surgery was chosen because of the complexity (e.g., poorly defined clinical borders, possible deep invasion, or prior irradiation), size or location (e.g. maximum conservation of tumor-free tissue is important).

Clinical settings that are supported by the criteria as denoted by the CPT codes and diagnosis codes listed in the associated article Billing and Coding: Mohs Micrographic Surgery will be considered for coverage when properly performed and the indications, procedures and findings/results are clearly and legibly documented within the beneficiary’s clinical record. Clinical settings noted to be inappropriate by the criteria and not otherwise covered in the LCD will be denied and should NOT be billed to Medicare as MMS.

Definitions:

1. 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), hands, feet, nail units, ankles, nipples/areola.
2. Area M:  Cheeks, forehead, scalp, neck, jawline, pretibial surface.
3. Area L: trunk and extremities (excluding pretibial surfaces, hands, feet, nail units and ankles).
4. Immunocompromised: a patient with HIV/AIDS, organ transplant, hematologic malignancy or pharmacologic suppression.
5. Genetic Syndromes: basal cell nevus syndrome, xeroderma pigmentosa, or other syndromes at high risk for skin cancer.
6. Healthy: no immunosuppression, no prior radiation therapy to affected area, no chronic infections and no genetic syndromes that predispose to skin cancer.
7. Prior Radiated Skin: patient has previously received therapeutic radiation in this area of the body.
8. Aggressive features:
   1. For Basal Cell Carcinoma
      1. Morpheaform, fibrosing, sclerosing
      2. Infiltrating
      3. Perineural
      4. Metatypical/keratotic
      5. Micronodular
   2. For Squamous Cell Carcinoma
      1. Sclerosing
      2. Basosquamous excluding keratotic BCC
      3. Small Cell
      4. Poorly or undifferentiated, i.e. high degree of polymorphism, high mitotic rate and/or low degree of keratinization
      5. Perineural or perivascular
      6. Spindle Cell
      7. Pagetoid
      8. Infiltrating
      9. Keratoacanthoma (KA) type: central facial
      10. Single Cell
      11. Clear Cell
      12. Lymphoepithelial
      13. Sarcomatoid
      14. Breslow depth below 2mm or greater
      15. Clark level IV or greater

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

1. Basal Cell Carcinoma
   1. Recurrent BCC of any size or unexpected positive margin on recent excision (healthy or immunocompromised or genetic syndrome(s))
      1. Aggressive Pathology
         1. Areas H, M and/or L
      2. Nodular Pathology
         1. Areas H, M and/or L
      3. Superficial Pathology
         1. Areas H and M only
         2. No coverage for area L
   2. Primary Aggressive
      1. Size ≤ 0.5 cm
         1. Areas H and M
         2. Area L would rarely be medically necessary
      2. Size ≥ 0.6 cm
         1. Areas H, M and L
   3. Primary Nodular BCC (healthy patient)
      1. Size ≤ 0.5 – 1 cm
         1. Areas H and M only
         2. No coverage for area L
      2. Size 1.1 – 2 cm
         1. Areas H and M
         2. Area L would rarely be medically necessary 
      3. Size ≥ 2 cm
         1. Areas H, M and L
   4. Primary Nodular BCC (immunocompromised patient)
      1. Size ≤ 0.5 cm
         1. Areas H and M only
         2. No coverage for area L
      2. Size 0.6 – 1 cm
         1. Areas H and M
         2. Area L would rarely be medically necessary
      3. Size ≥ 1.1 cm
         1. Areas H, M and L
   5. Primary Superficial BCC (healthy patient)
      1. Size ≤ 0.5 cm
         1. Area H
         2. Area M would rarely be medically necessary
         3. No coverage for area L
      2. Size ≥ 0.6 cm
         1. Areas H and M
         2. No coverage for area L
   6. Primary Superficial BCC (immunocompromised patient)
      1. Size ≤ 1.0 cm
         1. Areas H and M
         2. No coverage for area L
      2. Size > 1.0 cm
         1. Areas H and M
         2. Area L would rarely be medically necessary
   7. Primary BCC with no mention of sub-type
      1. Size ≤ 0.5 – 1 cm
         1. Areas H and M only
         2. No coverage for area L
      2. Size 1.1 – 2 cm
         1. Areas H and M
         2. Area L would rarely be medically necessary
      3. Size 2 cm
         1. Areas H, M and L
   8. Primary BCC with sub-types of adenoid, cystic, adamantoid, or fibroepithelioma of Pinkus
      1. Size ≤ 0.5 - 1 cm
         1. Areas H and M only
         2. No coverage for area L
      2. Size 1.1 – 2 cm
         1. Areas H and M
         2. Area L would rarely be medically necessary
      3. Size ≥ 2 cm
         1. Areas H, M and L
2. Squamous Cell Carcinoma
   1. Recurrent SCC of any size or unexpected positive margin on recent excision
      1. Aggressive Pathology
         1. Areas H, M and L
      2. Verrucous Pathology
         1. Area H
      3. KA-type SCC (Not central facial)
         1. Areas H, M and L
      4. In situ/Bowen
         1. Areas H and M
         2. Area L would rarely be medically necessary
      5. AK with focal SCC in situ; Bowenoid AK; SCC in situ, AK type
         1. Not covered
      6. Without aggressive histologic feature, < 2 mm depth without other defining features, Clark level ≤ III
         1. Areas H, M and L
   2. Primary aggressive SCC (healthy patients)
      1. Size – all
         1. Areas H, M and L
   3. Primary aggressive SCC (immunocompromised patients)
      1. Size – all
         1. Areas H, M and L
   4. Primary SCC without aggressive histologic features, < 2 mm depth without other defining features, Clark level ≤ III (healthy patients)
      1. Size ≤ 1.0 cm
         1. Areas H and M
         2. No coverage for area L
      2. Size 1.1 – 2 cm
         1. Areas H and M
         2. Area L would rarely be medically necessary
      3. Size > 2 cm
         1. Areas H, M and L
   5. Primary SCC without aggressive histologic features, < 2 mm depth without other defining features, Clark level ≤ III (immunocompromised patients)
      1. Size ≤ 1.0 cm
         1. Areas H and M
         2. Area L would rarely be medically necessary
      2. Size ≥ 1.1 cm
         1. Areas H, M and L
   6. Primary verrucous SCC (healthy or immunocompromised patients)
      1. All sizes
         1. Area H only
         2. No coverage for areas M and L
   7. Primary SCC KA type, not central facial (healthy patients)
      1. Size ≤ 1.0 cm
         1. Areas H and M
         2. No coverage for area L
      2. Size ≥ 1.1 cm
         1. Areas H, M and L
   8. Primary SCC KA type, not central facial (immunocompromised patients)
      1. Size ≤ 0.5 cm
         1. Areas H and M. Area L would rarely be medically necessary
      2. Size > 0.6 cm
         1. Areas H, M and L
   9. Primary in situ SCC/Bowen disease (healthy patients)
      1. Size ≤ 1.0 cm
         1. Areas H and M
         2. No coverage for area L
      2. Size 1.1 – 2 cm
         1. Areas H and M
         2. Area L would rarely be medically necessary
      3. Size > 2 cm
         1. Areas H, M and L
   10. Primary in situ SCC/Bowen disease (immunocompromised patients)
       1. Size ≤ 0.5 cm
          1. Areas H and M
          2. No coverage for area L
       2. Size 0.6 – 1 cm
          1. Areas H and M
          2. Area L would rarely be medically necessary
       3. Size ≥ 1.1 cm
          1. Areas H, M and L
   11. Primary AK with focal SCC in situ; Bowenoid AK; SCC in situ, AK type (healthy or immunocompromised patients)
       1. Any size
          1. Not covered
3. Basal or Squamous Cell Carcinoma
   1. Primary BCC or SCC regardless of sub-type, size or depth arising in:
      1. Prior irradiated skin,
      2. Traumatic scar,
      3. Area of osteomyelitis,
      4. Area of chronic inflammation/ulceration, or
      5. Patients with genetic syndromes predisposing to skin cancer
         1. Areas H, M and L
4. Lentigo Maligna and melanoma in situ
   1. Primary lentigo maligna (healthy or immunocompromised patients)
      1. Areas H and M
      2. Area L would rarely be medically necessary
   2. Locally recurrent lentigo maligna (healthy or immunocompromised patients)
      1. Areas H, M and L
   3. Primary melanoma in situ; non-lentigo maligna (healthy or immunocompromised patients)
      1. Areas H and M
      2. Area L would rarely be medically necessary
   4. Locally recurrent melanoma in situ; non-lentigo maligna (healthy or immunocompromised patients)
      1. Areas H, M and L
5. Other less common skin cancers
   1. Adenocystic carcinoma
      1. Areas H, M and L
   2. Adnexal carcinoma
      1. Areas H, M and L
   3. Apocrine/eccrine carcinoma
      1. Areas H, M and L
   4. Angiosarcoma
      1. Areas H, M and L would rarely be medically necessary
   5. Atypical fibroxanthoma
      1. Areas H, M and L
   6. Bowenoid papulosis
      1. Not covered
   7. Dermatofibrosarcoma protuberans
      1. Areas H, M and L
   8. Desmoplastic trichoepithelioma
      1. Areas H and M would rarely be medically necessary
      2. Area L not covered
   9. Extramammary Paget Disease
      1. Areas H, M and L
   10. Leiomyosarcoma
       1. Areas H, M and L
   11. Malignant fibrous histiocytoma
       1. Areas H, M and L
   12. Merkel Cell Carcinoma
       1. Areas H and M
       2. Area L would rarely be medically necessary
   13. Microcystic Adnexal Carcinoma
       1. Areas H, M and L
   14. Mucinous Carcinoma
       1. Areas H, M and L
   15. Sebaceous Carcinoma
       1. Areas H, M and L
   16. Rare Biopsy proven malignancies not otherwise specified
       1. Areas H, M and L would rarely be medically necessary

Limitations:

If a surgeon performs an excision using Mohs surgical techniques but does not personally provide the histologic evaluation of the specimen(s), the procedure codes for MMS included in the associated Billing and Coding Article may not be used. Standard excision codes should be chosen for such services.

Medicare is aware that a biopsy of the skin lesion for which Mohs surgery is planned may be necessary in order for the physician to determine the exact nature of the lesion(s) to be removed. Occasionally, that biopsy may need to be done on the same day that the Mohs surgery is planned. In order to allow separate payment for a biopsy and pathology on the same day as Mohs surgery, the -59 modifier is appropriate. The -59 modifier is also appropriate when a separate skin lesion, other than the lesion for which Mohs surgery is performed, is biopsied on the same day that the Mohs surgery is performed.

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.

If a prior biopsy of the site undergoing Mohs surgery has been previously performed within the last 60 days, the surgeon should make a reasonable effort to obtain those results rather than repeating the biopsy.

N/A

N/A

Documentation Requirements
Please refer to the Local Coverage Article 57477 Billing and Coding: MOHS Micrographic Surgery for documentation requirements that apply to the reasonable and necessary provisions outlined in this LCD.

Documentation must be available to Medicare contractors upon request.

The patient's medical record must contain documentation that fully supports the medical necessity for services included within this LCD in accordance with this LCD. This documentation should include, but is not limited to, relevant medical history, physical examination, and results of pertinent diagnostic tests or procedures including biopsy reports along with the procedural note.

Ad Hoc Task Force, Connolly SM, Baker DR, et al. AAD/ACMS/ASDSA/ASMS 2012 appropriate use criteria for Mohs micrographic surgery: a report of the American Academy of Dermatology, American College of Mohs Surgery, American Society for Dermatologic Surgery Association, and the American Society for Mohs Surgery [published correction appears in J Am Acad Dermatol. 2015 Apr;72(4):748]. J Am Acad Dermatol. 2012;67(4):531-550. doi:10.1016/j.jaad.2012.06.009

Other Medicare Administrative Contractor Policies

1. Current Procedural Terminology (CPT®), Professional Edition 2021). American Medical Association.