Biopsy coding: Pathology particulars

By Alexander Miller, MD, February 1, 2019

Now that the biopsy codes are stratified by biopsy technique — tangential, punch, and incisional — how should such techniques be transmitted to the pathologist/dermatopathologist ultimately reading the biopsy slides? Do different techniques make a difference for the physician reading the slides? Well, yes. Let’s examine why. 

Tangential biopsy specimens (CPT codes 11102, 11103) will consist of epidermis with or without underlying dermis. They are not full thickness, through the dermis. Consequently, both the physician doing the biopsy and the pathologist reading the slides should consider why this technique was selected. They should expect to see epidermis and/or dermis on a biopsy slide. Although the CPT definition of a tangential biopsy states that epidermis and/or dermis would be identified on a tangential biopsy, there are instances in which the epidermis is removed in a given lesion. In such situations, a tangential biopsy would reveal an absence of epidermis, or only remnants of epidermis along with dermis. These specimens would still be considered tangential biopsies.

Punch biopsies (CPT codes 11104, 11105) must be obtained with a punch tool, and must be full thickness specimens, with the punch depth penetrating into the subcutaneous space or tissue. Thus, one may see subcutaneous fat or muscle attached to the deep aspect of a punch biopsy, but not always. There are instances in which the subcutaneous tissue has either detached from the deep dermis or there is little to no subcutaneous tissue to be found deep to the dermis such as on the ventral ear pinna overlying cartilage.

Incisional biopsies (CPT codes 11106, 11107) may be submitted in any shape, but commonly would be fusiform in configuration. Similar to punch biopsies, the specimen should be full-thickness skin, penetrating into the subcutaneous space. Depending on the lesion being biopsied, an incisional biopsy may contain copious attached subcutaneous fat. However, seeing fat on the biopsy tissue is not required because penetration into a subdermal space does not stipulate attachment of fat or other subcutaneous tissue.

All biopsy modalities are used for sampling a lesion for diagnostic histopathology evaluation. If the intent is to remove the lesion and any dermis remains at the base of the wound, the procedure should be reported as a shave removal rather than a tangential biopsy. If the intent is to remove the entire lesion with margins through the entire thickness of the dermis, then a benign or malignant excision code (CPT codes 11400-11646) would be appropriate, regardless of the technique used.

Ideally, the physician reading a biopsy specimen should benefit from essential information that would help to generate optimal histopathology readings. Clinicopathological correlation aids in directing attention to tissue adequacy/inadequacy for reaching a given suspected diagnosis and helps the slide reader to focus upon characteristics that may support or refute a given differential diagnosis, or to realize that a specimen is adequate/inadequate for optimal evaluation. Pathology requests that include only patient identifiers and a location of the biopsy are inadequate. Requests that state: “Rule out cancer” supply very limited information. One would wonder: What kind of cancer and at what depth within the biopsy would such a cancer be expected? For example, if one suspects a deep malignancy, such as a dermatofibrosarcoma protuberans, and the biopsy is superficial, the pathologist may end up focusing upon the common epidermal-dermal malignancies and fail to comment upon a potential inadequacy of the specimen for diagnosis.

Similarly, if a pathology requisition states, “dermatitis,” and nothing more, one would have no way of determining whether the submitted tissue was adequate. A superficial tangential biopsy may be adequate for the diagnosis of contact allergic dermatitis but inadequate for the diagnosis of a deep granuloma annulare or an infectious granulomatous process. It helps, of course, to generate a clinically relevant differential diagnosis from the get-go and transmit it to the dermatopathologist. Sometimes the transmission is not done, and sometimes there is nothing to transmit because the individual doing the biopsy is unsure of what they are biopsying. Assuming that a dermatopathologist would magically extract a diagnosis from a submission lacking helpful information and/or from inadequately biopsied tissue may not be realistic.

What helpful information may be supplied on a pathology requisition? Below are suggestions:

• Specimen location

• Biopsy technique: tangential, punch, or incisional

• Clinical description may include:
  a. Lesion description (including size, possible depth)
  b. Dermatitis description
  

  c. Extent of lesion, such as a dermatitis (diffuse vs. localized)

• Prior treatment, such as with topical or systemic steroids, or surgical, chemical, or radiation treatment

• Clinical diagnosis/differential diagnosis

• Any other information one would like to receive from the dermatopathologist

What if you read your own slides? One certainly should not have to regurgitate charted information to oneself, as such details can be readily extracted from a chart reading.

Example 1: You use a blade to tangentially remove a dome-shaped, clinically benign nevus from the cheek of a patient who hates the mole and wants it removed. You report your service to the patient’s Medicare Administrative Contractor (MAC) as a tangential biopsy, CPT code 11102. The histopathology reveals a benign intradermal nevus, and the service is billed to the MAC with CPT code 88305.

Answer: Incorrect. The intent of the procedure was not diagnostic, and the procedure was cosmetic and not medically necessary. Therefore it should not be billed to a payer.

Removal of benign lesions that do not pose a threat to structure and function but, rather, constitute appearance annoyances, is not a covered Medicare service. The patient would have to be apprised of statutory non-coverage prior to the procedure. In such instances, the full expense is the patient’s responsibility. An Advanced Beneficiary Notice of Noncoverage (ABN), available from the MAC or CMS website (www.cms.gov/Medicare/Medicare-General-Information/BNI/ABN.html), would have to be signed by the patient prior to the service if Medicare billing were requested by the patient. Similarly, the patient should also sign a financial responsibility consent for claims submitted to private payers informing them of their financial responsibility, should the claim be denied by insurance as a non-covered service.

Example 2: You have an outside laboratory process tissue specimens and send you the slides for histopathology interpretation. The laboratory bills Medicare for slide preparation, and you bill Medicare for the professional component with CPT code 88304.26 or CPT code 88305.26. You list the date of service as the date that you read a slide and generate a report.

Answer: Correct. In general, Medicare directs that laboratory services be billed with the date of service as the date of specimen acquisition. However, histopathology is interpreted differently. The technical component (TC) should be billed with the date that the specimen was acquired. For some payers, the slide interpretation and report professional component (.26) is billed with the date of the reading and report. If one has an in-house processing lab, the global CPT code 88304 or 88305 would only be billed if the interpretation/report was done on the day the specimen was acquired. If the specimen is acquired on a date different from that of the slide reading/report, check directly with the payer for specific guidance. For example, some private insurers require that both the technical and professional services be billed with the specimen acquisition date of service.

A note of gratitude to the Healthcare Finance Committee and Dermatopathology Rapid Response Committee for their contribution to the development of this article.

Cracking the Code clarification

In the December Cracking the Code column, Biopsy Coding in 2019: Part 2, the fifth example requires clarification. The example has been clarified online and is as follows, with updates in bold:

Example 5: During a complete skin examination of a patient with dysplastic nevi you identify a 1.2cm-wide pigmented patch suspicious for a melanoma.

You proceed to do a diagnostic full-thickness, into subcutaneous fat removal of the lesion with 3 mm clinical margins. You select CPT 11602, excision, trunk, 1.1-2.0 cm diameter, as the histopathology confirmed a melanoma.

Answer: Correct/True. Your intent was to diagnose the lesion with a full thickness excision (removal) with margins. This meets the definition of an excision incisional biopsy. An incisional biopsy is a sampling of a lesion, which implies a partial removal and/or an absence of intent to remove a lesion full-thickness, with margins. The corollary of this is that an incisional biopsy code, 11106, is inappropriate. This procedure should neither be reported or adjudicated as an excision be reported or adjudicated as an incisional biopsy.

Additional DermWorld Resources