IGF1 and nasopharyngeal carcinoma: The analysis confirmed that advanced T stage (OR = 4.512, P<0.001), N stage (OR = 5.981, P<0.001), high EBV DNA load (OR = 3.551, P = 0.002), and elevated serum levels of VEGFC (OR = 3.917, P<0.001), VEGFR-3 (OR = 1.503, P = 0.003), and IGF1 (OR = 2.418, P<0.001) were independent risk factors for NPC metastasis (Table 4).