Case Report: CYLD cutaneous syndrome with malignant transformation to spiradenocarcinoma: cooperative effects of CYLD truncation and an MSH2 clamp-domain variant in an Ecuadorian patient

This is the first genetically confirmed case of CCS in Ecuador and among the few reported in South America. Beyond expanding the geographic spectrum, our findings highlight the value of integrating genomic and protein analyses to uncover cooperative mechanisms of malignant progression. Such integrative genomic approaches refine diagnosis, enhance genotype-phenotype interpretation, and deepen understanding of malignant transformation in CCS, particularly in underrepresented populations.