Active angiogenesis can be observed in both eutopic uterine tissue and EM lesion, and high expression of angiogenic genes such as vascular endothelial growth factor-A (VEGF-A) and hepatocyte growth factor (HGF) was detected in ectopic endometriotic tissues (Delbandi et al., 2020). The gene discussed is VEGFA; the disease is erythema multiforme.