Approximately 12% of patients with melanoma developed subsequent squamous cell carcinoma, and the occurrence was more common among men, whites, older patients and those with a history of nonmelanoma skin cancer, according to recent study results.
Researchers studied 6,378 Kaiser Permanente Northern California (KPNC) members (mean age, 60.9 years; 56.6% men) who received a melanoma diagnosis between 2000 and 2005. The patients were followed through 2009, with 1,462 meeting criteria for squamous cell carcinoma (SCC) pathology review. There were 766 patients with defined SCC (69.7% men).
The crude SCC incidence rate was 2.41 per 100 person-years, and men had nearly twice the SCC incidence rate (3.1; 95% CI, 2.84-3.37) compared with women (1.59; 95% CI, 1.39-1.81). It also was greater in older patients, increasing for every 10-year increment.
Men had a greater SCC risk in adjusted models stratified by age (HR=1.43; 95% CI, 1.22-1.67), as did patients with a history of nonmelanoma skin cancer (HR=2.56; 95% CI, 2.19-2.98) and higher tumor sequence numbers (HR=1.35; 95% CI, 1.01-1.8). Hispanics, blacks, Asians, American-Indians and Pacific Islanders had lower SCC risk (HR=0.39; 95% CI, 0.17-0.86) when adjusted.
Study limitations included that SCC risk was not examined in KPNC members without melanoma, the researchers reported.
“Melanoma survivors whose melanoma arose on sun-exposed skin may also have a slightly increased risk of SCC,” the researchers concluded. “Clinicians should be vigilant about checking for SCCs during skin examinations, especially among individuals at high risk, and they should counsel melanoma survivors about the increased risk for SCCs and educate these patients on methods for detecting potential SCCs during skin self-examinations.”
Disclosure: The researchers report no relevant financial disclosures.