Soft Tissue Tumors

Question:

My physician told me to use CPT code 21011 for an excision of a 1.2 cm cutaneous basal cell carcinoma on the scalp. Is this correct?

Answer:

This is a great question. You only use soft tissue tumor codes for the excision of non-cutaneous origin tumors such as lipomas, sarcomas, and hemangiomas. For cutaneous lesions such as basal cell carcinoma 1.2 cm, you would report 11622 (excision, malignant lesion including margins, scalp, neck, hands, feet, genitalia; excised diameter 1.1 to 2.0 cm). For any excision of a cutaneous lesion, they are reported as malignant excisions (116xx) based on anatomic area and cm size.

*This response is based on the best information available as of 4/24/25.

First Visit for a Chronic Condition

Question:

I am seeing a patient for the first time in the office and they are reporting to me that they have had psoriasis for over two years and their symptoms are worsening; is this problem a level 3 (99203) or 4 (99204)?

Answer:

If your documentation indicates the patient has a chronic condition that is worsening, then the complexity of the problem addressed is moderate, even if this is their first visit to you. However, keep in mind there are three elements to Medical Decision Making:

• Complexity of Problem(s) Addressed

• Amount and/or Complexity of Data to be Reviewed or Analyzed

• Risk of Mortality and/or Morbidity of Patient Management

Two of the three elements on the risk table must be met.  For example, if the condition managed is chronic psoriasis worsening and you write a prescription for a topical medication, the complexity of the problem addressed is moderate with moderate risk. This would indicate a level four new patient visit (99204).

*This response is based on the best information available as of 4/10/25.

Destruction of Seborrheic Keratosis

Question:

I have a patient encounter. I need to code for a patient with 3 SK’s, 2 on the right forearm and 1 on the left forearm. The physician froze the lesions. I am thinking I should code 17000 x 1 and 17003 x 2. Is this correct?

Answer:

The correct CPT code to report for destruction of SK’s is 17110 (destruction benign lesions other than skin tags or cutaneous vascular proliferative lesions up to 14). You will only report CPT code 17110 with 1 unit since the code includes 1-14 lesions. CPT codes 17000-17004 is used to report the destruction of premalignant lesions for example an AK (actinic keratosis).

*This response is based on the best information available as of 3/27/25.

Biopsy Following Mohs Surgery

Question:

I have received conflicting information and would appreciate clarification. I had a patient referred to me by a family physician for a possible basal cell carcinoma. The patient has never had a biopsy. I did a punch biopsy and the diagnostic frozen section which confirmed a morpheaform basal cell carcinoma and performed a stage 2 Mohs procedure 17311 and 17312. Can I bill for the biopsy even when I did the Mohs surgery on the same date?

Answer:

The answer to your question is yes, you can bill the punch biopsy (11105-59) and the frozen section (88331-59) in addition to Mohs surgery. If a biopsy has not been performed within the last 60 days prior to Mohs surgery, you can report the biopsy and frozen section. Make sure you append Modifier 59 to the biopsy and frozen section to identify that the procedure was distinct and separate.

*This response is based on the best information available as of 3/13/25.

Billing Stages for Mohs

Question:

I am very confused. I am new to coding for Mohs procedures. The Mohs surgeon performed a procedure on the patient’s scalp in 5 stages. I spoke with the Mohs surgeon about billing over 4 stages in one area using CPT code 17312. He billed 17311 for the first stage and 17312 with 4 units for a total of 5 stages. In each stage, the documentation states that 1 tissue block was mapped. I think we should bill CPT 17315 for the last stage instead of 17312 since it is the 5th stage. Can you clarify if this is the case or if 17312 with 4 units is correct.

Answer:

I agree with your Mohs surgeon. The only time you use 17315 is when there are more than 5 tissue blocks per stage. Based on the information you have provided each stage indicates 1 block. CPT code 17311 should be reported for stage 1 and 17312 is reported for each additional stage (4).

*This response is based on the best information available as of 2/27/25.

Skin Cancer Screening

Question:

What is the correct ICD-10-CM code for a skin screening exam for a patient who has a history of malignant melanoma?

Answer:

You should report 2 diagnosis codes; ICD-10-CM Z12.83 for the encounter for malignant neoplasm of skin and Z25.820 (personal history of malignant melanoma of skin).

*This response is based on the best information available as of 2/13/25.