EGFR and vitamin D deficiency: No interaction was found between 25(OH)D and tumor mutational status for the effect on survival, with increased risk of death associated to vitamin D deficiency both in RAS/BRAF wild-type tumors (treated with anti-EGFR based first-line therapy) and in RAS or BRAF mutated tumors (treated with anti-VEGF based regimen), HR 2.15 and 1.87, respectively, p for interaction = 0.773 (Figure 3).