Immunohistochemical staining was performed on pathological specimens to assess CD138 expression (Fig. 1F), which indicated a correlation between CD138 expression and early clinical pathological stage (Table S5), and patients in the high tumor-infiltrating PC group had a better disease-free survival (P = 0.037) and overall survival (P = 0.019) (Fig. 1F). This evidence concerns the gene SDC1 and pachyonychia congenita.