Actinic keratoses may predict skin cancers in older adults

TOPLINE:

Older adults with actinic keratoses (AKs) have a higher risk for skin cancers, including squamous cell carcinoma (SCC), basal cell carcinoma (BCC), and melanoma.

METHODOLOGY:

• AKs have been associated with a small risk for cutaneous SCC, but associations with risk for other skin cancers have not been well studied.
• AKs may be a marker of overall skin cancer risk, but guidelines for AK management lack recommendations for follow-up cancer surveillance.
• The researchers reviewed data from a random sample of 5 million fee-for-service Medicare beneficiaries treated for AKs from 2009 through 2018 in the United States. Patients with seborrheic keratoses (SKs) were included as comparators, and patients with a history of skin cancer were excluded.
• The primary outcome was the first surgically treated skin cancer, including SCC, BCC, and melanoma.

TAKEAWAY:

• A total of 555,945 adults with AKs and 481,024 with SKs were included. The mean age was approximately 74.0 years. More than half were female. Most were non-Hispanic White.
• Among patients with AKs, the absolute risk for any skin cancer after the first AK was 6.3%, 18.4%, and 28.5% at 1, 3, and 5 years, respectively.
• Patients with AKs had a significantly increased relative risk for any skin cancer compared with those with SKs (adjusted hazard ratio [aHR], 2.17) and separately for keratinocyte carcinoma (aHR, 2.20), SCC (aHR, 2.63), BCC (aHR, 1.85), and melanoma (aHR, 1.67).
• Although AKs are not considered a biological precursor of melanoma or BCC, the results suggest that AKs may be clinical indicators of increased UV exposure that subsequently increases the risk for skin cancer.

IN PRACTICE:

“The present results highlight the importance of developing evidence-based guidelines for follow-up skin cancer surveillance in patients with AKs, optimally including measures of AK burden,” the researchers wrote.

SOURCE:

The lead author on the study was Cassandra Mohr, BS, with corresponding author Mackenzie R. Wehner, MD, MPhil, of The University of Texas MD Anderson Cancer Center, Houston. The study was published online in JAMA Dermatology .

LIMITATIONS:

The study population of Medicare beneficiaries aged 65 years or older may not be a nationally representative sample, and surveillance bias may contribute to the increased risk for skin cancer in patients with AKs. The use of both ICD and CPT codes may underestimate the number of skin cancers because of cases that were treated nonsurgically.

DISCLOSURES:

The study was supported by the National Cancer Institute of the National Institutes of Health, the Cancer Prevention and Research Institute of Texas, and The University of Texas Rising STARS program. The researchers had no financial conflicts to disclose.

A version of this article appeared on Medscape.com.