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Soo Park, MD
Soo Park, MD
Posted: Thursday, June 19, 2025
The number of targetable mutations does not significantly differ across cutaneous skin cancers, according to Connor Yost, DO, of Creighton University School of Medicine, Phoenix, and colleagues. In a retrospective analysis published as part of the 2025 ASCO Annual Meeting (Abstract e21555), researchers also observed nonsignificant subtype-specific patterns, including the highest number of unique mutations in melanoma—driven by BRAF and TP53—and a high frequency of TP53 mutations in squamous cell carcinoma.
The investigators focused on 50 patients who were diagnosed with cutaneous skin cancer (melanoma: n = 28; squamous cell carcinoma: n = 13; basal cell carcinoma: n = 5; Merkel cell carcinoma: n = 4). The median number of targetable mutations was 2.3 in melanoma, 3.7 in squamous cell carcinoma, 2.3 in basal cell carcinoma, and 6.9 in Merkel cell carcinoma; these values were not found to significantly differ (P = .31).
Patients with melanoma had the highest number of unique mutations (n = 34), followed by those with squamous cell carcinoma (n = 30), basal cell carcinoma (n = 14), and Merkel cell carcinoma (n = 11). The most frequent mutations in melanoma involved BRAF (n = 17), TP53 (n = 7), and CDKN2A (n = 8). In squamous cell carcinoma, TP53 mutations predominated (n = 13), whereas basal cell carcinoma was associated with mutations in TP53 (n = 6), PTCH1 (n = 2), and ASXL1 (n = 2). Merkel cell carcinoma was characterized by RB1 (n = 2) and EGFR (n = 2) mutations. According to the investigators, despite these subtype-specific patterns, the overall prevalence of targetable mutations did not significantly differ among the four groups.
“These findings suggest that targetable mutations may be similarly prevalent across subtypes [of cutaneous skin cancers], underscoring the need for larger studies to clarify their clinical significance and inform targeted therapy,” the investigators concluded.
Disclosure: The study authors reported no conflicts of interest.
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