**4.1 Origin**

In general, it is believed that chordoma cells are initiated from the embryonic notochord remnants [9]. It is also projected that notochordal remnants are derived from the embryonic notochord and reside in the region of an embryo where the embryonic notochord was existing. It is assumed that notochordal remnants stay dormant in maximum cases but might be transformed into malignancies. Yamaguchi and his colleagues have stated a link between persistent notochordal remnants and Chordoma [10]. Currently, cancer stem cell theory has given more details about the embryonic transformations and stem-like cells in Chordoma may show stemness, gene expression, and differentiation [9].

Chordomas may also be an outcome of direct malignant transformation of the notochordal remnant, deprived of a benign notochordal tumor intermediary stage. Otherwise chordoma may be inferred from benign notochordal cell tumor through malignant transformation (**Figure 1**) making another root of chordomagenesis.
