Head and neck melanoma associated with more adverse prognostic features

Key takeaways:

• Head and neck melanomas were thicker and had higher ulceration rates vs. melanoma on other sites.
• Stage IV head and neck melanoma patients had better survival outcomes after checkpoint inhibitor immunotherapy.

Researchers confirmed that head and neck melanomas have distinct biological characteristics that make it more adverse to patients yet more responsive to immunotherapy, according to a study.

“There is accumulating evidence that primary cutaneous head and neck melanoma may represent a distinct clinicopathological entity compared to cutaneous melanoma of other sites, with different patient demographics, primary melanoma pathological features and outcomes,” Andrew T. Li, MBBS, of the Melanoma Institute Australia, Royal Prince Alfred Hospital and Faculty of Medicine and Health at the University of Sydney in Australia, and colleagues wrote. “If true, this has important implications for selection of therapeutic options, particularly considering recent developments in BRAF-targeted therapy and immune checkpoint inhibitor immunotherapy (ICI) that have revolutionized treatment for advanced melanoma.”

While the evidence is mounting, many experts still hold varying opinions over the severity of head and neck melanoma compared with melanoma of other sites. To address these controversies, a group of researchers analyzed and compared the characteristics of head and neck melanoma and melanoma on other sites in 3,007 and 10,637 patients, respectively.

Results showed that head and neck melanoma had more adverse pathological features.

Head and neck melanoma typically affected older patients vs. melanoma on other sites (median age, 65.9 vs. 58.5 years; P < .001).

Head and neck melanomas also had higher median Breslow thickness (1.7 mm vs. 1.2 mm; P < .001) and ulceration rates (21.2% vs. 18.2%; P < .001) compared with melanoma on other sites.

Locoregional control and distant metastasis-free survival were also worse among patients with head and neck melanoma, who were 1.17 times and 1.25 times more likely to experience these outcomes, respectively, compared with other melanoma patients (P < .001 for both).

On the other hand, stage IV head and neck melanoma patients had better melanoma-specific (HR = 0.56; P = .001) and overall survival (HR = 0.57; P < .001) after receiving ICI than those with melanoma on other sites.

“The significantly better survival outcomes of patients in our study who developed stage IV disease and received ICI further suggest that these melanomas may have distinct biological characteristics,” the authors wrote.

One possible difference may be the abundance of BRAF V600K mutations, which respond well to ICI therapy, in head and neck melanoma vs. melanoma on different sites.

“Further studies would be useful to correlate the molecular features and clinical outcomes of [cutaneous head and neck melanoma] and its subsites,” the authors concluded.