The inflammatory tumor microenvironment and its main components, non-tumoral cells (different immune cell types, fibroblasts tumor-associated), soluble factors secreted by both tumoral and non-tumoral cells, such as VEGF, FGF, EGF, IL-6, TNFα and immune checkpoint molecules, play an impact on endometriosis and tumor and malignancy development [45,46]. This evidence concerns the gene IL6 and endometriosis.