The etiology of recurrent chordoma presenting as a neck mass: metastasis vs. surgical pathway seeding.

Chordomas are rare tumors of notochordal origin that arise along the vertebral axis. These slowly growing yet highly destructive tumors are associated with an alarming rate of recurrence, although surgical resection followed by proton, proton/photon, or conventional radiotherapy has been somewhat successful in terms of recurrence-free survival. Still, recurrent disease as a result of metastasis or surgical pathway seeding does occur. We retrospectively reviewed the case of a 64-year-old woman who presented with a left neck mass at level II. She had a history of recurrent chordomas involving the occipital portion of the clivus that had been treated with multiple resections and proton-beam irradiations over a period of several years. The new mass was found to have infiltrated the superior end of the sternocleidomastoid muscle. Neck dissection was performed. Pathology revealed no lymphoid tissue in the main specimen and no evidence of chordoma in any of the lymph nodes. We believe that this latest clival chordoma might have occurred as a result of surgical pathway seeding during a previous operation anterior to the sternocleidomastoid muscle, although metastasis cannot be ruled out. We also review the literature on clival and skull base chordomas as it relates to recurrence, metastasis, and seeding.