The proportion of somatic BRCA2 mutation carriers among patients with any stage PC was available from 10 articles, for a total of 3229 patients, and was equal to 6.29% (95% CI: 3.79–9.38), with significant heterogeneity (I2 = 89.14%; p < 0.0001) (Figure 3b). This evidence concerns the gene BRCA2 and pachyonychia congenita.