ðə pɹɑːksˈɪmᵻɾi ʌv kɔːɹdˈoʊməz tə vˈaɪɾəl nˌʊɹɹəlˈɑːdʒɪkəl stɹˈʌktʃɚz sˈʌtʃ ɐz ðə bɹˈeɪn stˈɛm ænd nˈɜːvz lˈɪmɪts ðə dˈoʊs ʌv ɹˌeɪdɪˈeɪʃən ðæt kæn sˈeɪfli biː dᵻlˈɪvɚd.
The proximity of chordomas to vital neurological structures such as the brain stem and nerves limits the dose of radiation that can safely be delivered.