** This article was reviewed and updated on December 16, 2023. **
In this article, we discuss actinic keratosis and coding for its removal in ICD-10-CM and CPT. The symptoms, causes, diagnosis, and treatment are discussed. Furthermore, a coding example with step-by-step instructions is provided to show you how to select the right ICD-10-CM and CPT codes for cryotherapy to destroy seven of these lesions.
What Is Actinic Keratosis?
Actinic keratosis (AK), also known as solar keratosis or senile keratosis, is a crusty, scaly patch on a person’s skin that develops from years of exposure to ultraviolet rays, either from the sun or from artificial sources such as tanning beds. It is most commonly found on the face, lips, ears, back of your hands, forearms, scalp, or neck in people who are middle-aged or older.
There is rarely just one keratosis, so you will often see the term “keratoses” to mean more than one. According to the American Academy of Dermatology, actinic keratosis is considered the most common type of premalignant lesion that may turn into skin cancer.
According to the Skin Cancer Foundation:
- Actinic keratosis is the most common precancer; it affects more than 58 million Americans.
- More than 419,000 cases of skin cancer in the U.S. each year are linked to indoor tanning, including about 168,000 squamous cell carcinomas.
- More people are diagnosed with skin cancer each year in the U.S. than all other cancers combined.
- One in five Americans will develop skin cancer by the age of 70.
- Regularly using an SPF 15 or higher sunscreen reduces the risk of developing squamous cell carcinoma by about 40 percent.
Common Symptoms of Actinic Keratosis
Actinic keratoses develop when the top layer of skin becomes badly damaged, and this can lead to additional AKs. These lesions may be elevated and resemble warts, and the color can be red, tan, white, pink, or flesh-toned. They can vary in size from an eighth to a quarter of an inch.
Although AKs can take years to develop, the American Osteopathic College of Dermatology reports that a small percentage of actinic keratosis lesions eventually turn into a type of skin cancer called squamous cell carcinoma (SCC), the second most common type of skin cancer in the United States.
Symptoms that individuals should watch for are:
- Patch on the skin that feels rough but cannot be seen
- Patch or growth that feels rough and painful when rubbed
- Itching or burning skin
- Constant dryness of the lips
These lesions can come and go. One AK may appear on the skin and remain for months before falling off and disappearing, and the skin can feel smooth all of a sudden. Still, many AKs can come back again within a few days to a few weeks. Or a person may go outdoors without sun protection, and the keratoses will, in many cases, return. Even if lesions don’t come back, the patient should see a dermatologist.
Main Causes of These Crusty Lesions
Chronic exposure to the sun accounts for most cases of actinic keratosis. Other causes include ultraviolet radiation from tanning beds, extensive exposure to X-rays, and extensive exposure to industrial chemicals. Damage can occur when a person spends short periods of time in the sun, as well as on cloudy days. Although it may be cloudy, 70 to 80 percent of the sun’s ultraviolet (UV) rays can still pass through the clouds. For those individuals who use tanning beds and sun lamps, the keratoses frequently appear much earlier.
When UV rays hit the skin, the rays damage the skin. The body can repair some of the damage in a young person, but over time, the body is less able to repair it. The effects eventually are UV-damaged skin, which turns into actinic keratosis if the person continues to be exposed to UV rays.
Who is at Risk of Actinic Keratosis?
People who live in places that get intense sunlight all year, such as Florida and Southern California, are at increased risk of developing actinic keratosis. As a matter of fact, the closer to the equator one lives, the earlier a person may develop AKs.
People who are more likely to develop AKs have the following traits:
- Fair skin
- Hair color that is naturally blond or red
- Eyes that are blue, green, or hazel
- Skin that freckles or burns when in the sun
- 40 years of age or older
- Weak immune system (such as in HIV-positive patients)
A weak immune system may be due to a medical condition that makes the skin overly sensitive to UV rays. This can occur in a person who works with substances that contain polycyclic aromatic hydrocarbons (PAHs), such as coal or tar. Roofers would be in this group, as they work with tar and spend a lot of time outdoors. In general, men have a slightly higher risk than women of developing AKs since they tend to spend more time outdoors and use less protection from the sun than women.
Making a Diagnosis
Dermatologists diagnose actinic keratoses by performing a thorough examination of the patient’s skin. If the dermatologist detects a thick growth or one that resembles skin cancer, he or she may perform a skin biopsy. This can be done during the office visit. If the physician finds the skin growth early and immediately begins treatment, skin cancer is usually cured.
The objective of treatment is to destroy the keratoses, and this can take more than one type of treatment. Fortunately, there are many treatment options available, and some can be performed in the physician’s office. Other treatments can be used at home.
Procedures Performed in the Office
A physician may perform one of the following procedures in the office:
- Cryotherapy. The most common treatment for actinic keratoses, freezing is done to destroy the visible lesions using liquid nitrogen. Anesthesia is not needed, and it produces no bleeding. Many times, the treated skin begins to blister and peel off within a few days to a few weeks. Once the skin heals, it may leave a small white mark.
- Chemical peel. This strong medical chemical peel destroys the top layers of skin. The area that is treated will become inflamed and sore, but it will be replaced by healthy new skin. A salon cannot provide this peel, nor can an in-home kit.
- Curettage. Your dermatologist uses a curette to carefully remove the lesion by scraping away the abnormal tissue. Local anesthesia is used. This method is useful when treating a small number of AKs that are particularly thick. Electrosurgery may be used afterward to remove any additional damaged tissue. Electrosurgery burns or cauterizes the skin and soon replaces it with healthier skin.
- Photodynamic therapy (PDT). A solution is first applied to the skin to make it more sensitive to light. A few hours later, a blue light or a laser light is used to shine on the treated skin. This light activates the solution and destroys the AKs, and a new healthy skin eventually replaces the healing skin.
- Laser resurfacing. This is similar to a chemical peel in that a laser can be used to remove the top layer of skin. This procedure destroys AK cells and leaves the skin feeling raw and sore. Within a couple of weeks, the skin will have healed and replaced by a healthier new skin.
Prescription medications to be used at home include:
- 5-fluorouracil (5-FU) cream. This is a cream that you apply to the skin. It causes the skin to turn red and crusty, but it is only temporary. Patients typically apply 5-FU twice daily for 2 to 4 weeks or longer if needed. The cream causes sun-damaged skin to become raw and irritated, but healthy skin will replace it. If the person has thick AKs, cryotherapy or another treatment may need to be added to the treatment regimen.
- Diclofenac sodium gel. For patients with many AKs, this non-greasy gel may need to be applied twice a day for about two to three months. The skin should be protected from the sun during this time. Once the gel has been stopped, the best results will appear in about 30 days. However, some AKs may not go away. If this occurs, another treatment, such as cryotherapy, may be recommended.
- Imiquimod cream. This cream should be applied to the skin based on your dermatologist’s recommendation. It helps boost your immune system so that your body can rid itself of diseased skin cells. This medication is usually applied for several weeks, and it can cause redness and swelling of the skin. Once the medicine is stopped, the skin will heal.
- Ingenol mebutate gel. This gel boosts the body’s immune system and is also a type of chemotherapy for the skin. One formula treats AKs that appear on the head and scalp, and it is applied to the skin on three consecutive days. The other formula treats AKs on the arms, legs, and torso and is applied on two consecutive days. Both formulas can quickly cause redness and swelling, but this will clear up as the skin heals.
Because there is no one-treatment-fits-all for actinic keratoses, researchers continue to look for new treatments.
Only a few actinic keratoses may develop in some people, in which case treatment is not always needed. Their AKs clear up on their own. Be that as it may, people who develop many AKs will need to see a dermatologist. Going without treatment can cause the skin damage to turn into squamous cell carcinoma. If the patient has frequent checkups, the physician can diagnose the skin cancer early, remove it, and hopefully cure it. Some people may need to return for a checkup every 8 to 12 weeks, and others may only need a checkup once or twice a year.
Actinic Keratosis and Coding for its Removal – Coding Exercise
Let’s look at the following coding scenario:
A 61-year old female patient presents to her dermatologist today with seven crusty, scaly lesions on her hands and forearms. She spends a lot of time outdoors, mainly working in her gardens, and many times she goes without adequate sunscreen. She reports that she does not use tanning beds. A diagnosis of actinic keratosis is confirmed, and she is counseled on the need for regular use of appropriate sunscreens. Cryotherapy is performed to destroy the seven lesions.
The appropriate codes assigned are:
CPT: 17000, 17003 x 6
Assigning for CPT
Finding the correct CPT code(s) for the destruction of benign, premalignant, and malignant lesions can be a little tricky. These codes can be found throughout the CPT coding manual in different systems, including the integumentary, female genital, male genital, digestive, and eye and ocular systems. In this case, the correct CPT codes are located in the Integumentary System.
In this coding scenario, we can start by looking in the Alphabetic Index of the CPT coding manual under Skin, destruction, premalignant, 17000-17004. We know that actinic keratosis is a premalignant lesion based on the information we learned above. In the Tabular, code 17000 can be verified as Destruction (e.g., laser surgery, electrosurgery, cryosurgery, chemosurgery, surgical curettement), premalignant lesions (e.g., actinic keratoses); first lesion.
Another way to find the code is to look in the Alphabetic Index under Destruction, lesion, skin 17000-17286, 96567, 96573-96574.
CPT Coding Guidelines
According to the CPT guidelines, “destruction means the ablation of benign, premalignant or malignant tissues by any method, with or without curettement, including local anesthesia, and not usually requiring closure. Any method includes electrosurgery, cryosurgery, laser and chemical treatment. Lesions include condylomata, papillomata, molluscum contagiosum, herpetic lesions, warts (i.e., common, plantar, flat), milia, or other benign, premalignant (e.g., actinic keratoses), or malignant lesions.”
If local anesthesia is used, it is covered by code 17000 and should not be reported separately.
Since the documentation states there were seven actinic keratoses destroyed, we need a code to describe the other six keratoses that were destroyed.
Per the CPT coding guidelines, code 17003 should be assigned for each lesion from the second through the fourteenth. Therefore, we need to report 17003 x 6 for the remaining six lesions. CPT code 17003 is an add-on code and should never be reported alone. If 15 or more lesions had been destroyed, CPT code 17004 would be reported without 17000 or 17003.
So, our CPT codes are 17000, 17003 x 6.
Assigning for ICD-10-CM
When coding for actinic keratosis in ICD-10, be sure to look at the clinical documentation for the type of keratosis diagnosed and whether it is inflamed. In addition, the location of the growths should be documented, along with any contributing factors, such as exposure to a tanning bed.
Actinic keratosis is located in the ICD-10-CM coding manual in Chapter 12: Diseases of the skin and subcutaneous tissue (L00-L99), block L55-L59, Radiation-related disorders of the skin and subcutaneous tissue, category L57, Skin changes due to chronic exposure to nonionizing radiation. Nonionizing radiation means it is low-energy radiation that can come from sources such as power lines, microwaves, infrared, ultraviolet, and visible radiation.
To find the diagnosis code in the Alphabetic Index of the ICD-10-CM coding manual, look up Keratosis, actinic L57.0. L57.0 is also the default code for Keratosis. When verifying this code in the Tabular, L57.0 describes actinic keratosis, actinic keratosis NOS, senile keratosis, and solar keratosis.
An Excludes2 note listed at the beginning of Chapter 12, Diseases of the Skin and Subcutaneous Tissue (L00-L99) states:
- certain conditions originating in the perinatal period (P04-P96)
- certain infectious and parasitic diseases (A00-B99)
- complications of pregnancy, childbirth and the puerperium (O00-O9A)
- congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
- endocrine, nutritional and metabolic diseases (E00-E88)
- lipomelanotic reticulosis (I89.8)
- neoplasms (C00-D49)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
- systemic connective tissue disorders (M30-M36)
- viral warts (B07.-)
An Excludes2 note means if any of the conditions listed are not part of the condition represented by the main code, they may be reported along with the main code, when appropriate.
Additional Code Note at L57
There is a note at L57 that states that an additional code should be reported to identify the source of the ultraviolet radiation (W89).
Hence, if the documentation had stated the patient’s actinic keratosis was caused by, say, the use of tanning beds, an additional code would need to be reported from category W89, Exposure to man-made visible and ultraviolet light. There are various code descriptions listed in this category, which include:
- 0 Exposure to welding light (arc)
- 1 Exposure to tanning bed
- 8 Exposure to other man-made visible and ultraviolet light
- 9 Exposure to unspecified man-made visible and ultraviolet light
W89.1- is the subcategory for Exposure to tanning bed. These codes require a seventh character for the encounter: A (initial), D (subsequent), or S (sequela). In addition, placeholders “X” are required as fifth and sixth characters.
So there we have it. The ICD-10-CM code for this scenario is L57.0.
I submitted this article to BC Advantage/www.billing-coding.com for their publication under the title, “Actinic Keratosis – Don’t Let it Turn Into Skin Cancer.” It is reprinted here with their permission.