BRCA2 and pachyonychia congenita: The proportion of somatic BRCA2 mutation carriers among patients with metastatic PC was available from six articles, for a total of 1384 patients, and was equal to 10.26% (95% CI: 7.92–12.85), without significant heterogeneity (I2 = 38.42%; p = 0.1498) (Figure 3d).