This study introduces novel molecules to be considered as non-invasive biomarkers in PC (e.g., miR-320a, miR-93-5p, B2M, CRP, and TIMP-1), encouraging further studies, including those of a prospective nature, aimed at deepening the understanding of their role in PC and to support the validation of different miRNA/protein combinations directly in the sera/plasma of PC patients for early diagnostic and prognostic purposes. This evidence concerns the gene B2M and pachyonychia congenita.