Factors Predicting Recurrence after Resection of Clival Chordoma using Variable Surgical Approaches and Radiation Modalities

Introduction: Clival chordomas frequently recur because of the location and invasiveness. We investigated clinical, operative, and anatomic factors associated with clival chordoma recurrence.

Methods: We conducted a retrospective review of clival chordomas treated at our center from 1993 to 2013.

Results: A total of 50 patients (59% male) with median age of 59 years (range, 8–76 years) were newly diagnosed with clival chordoma of mean diameter 3.3 cm (range, 1.5–6.7). Symptoms included headaches (38%) and diplopia (36%). The procedures included transsphenoidal (n = 34), transoral (n = 4), craniotomy (n = 5), and staged approaches (n = 7). Gross total resection (GTR) rate was 52%, with 76% mean volumetric reduction. GTR rate improved over time, from 35% for the first quarter of patients to 88% for the last quarter. Although the lower-third of the clivus was the least likely superoinferior zone to contain tumor (upper-third = 72%, middle-third = 82%, and lower-third = 42%), it most frequently contained residual tumor (upper-third = 33%, middle-third = 38%, and lower-third = 63%; p < 0.05). Symptom improvement rates were 61% (diplopia) and 53% (headache). Postoperative radiation included proton beam (n = 19), cyberknife (n = 7), IMRT (n = 6), external beam (n = 10), and none (n = 4). At the last follow-up, 23 of 47 patients with follow-up (49%) remain disease-free or have stable residual. Lower-third of clivus progressed most after STR (upper-third = 14%,mid-third = 55%, and lower-third = 57%), and GTR (upper-third = 33%,mid-third = 50%, and lower-third = 67%). In a multivariate Cox proportional hazards model, male gender (HR = 1.2, p = 0.03), STR (HR = 5.0, p = 0.02), and the preoperative presence of tumor in the middle-third (HR = 1.2, p = 0.02) and lower-third (HR = 1.8, p = 0.02) of the clivus increased recurrence or progression of residual, whereas radiation modality did not influence increase recurrence or progression of residual.

Conclusion: Our findings underscore long-standing support for GTR as reducing chordoma recurrence. The lower-third of the clivus frequently harbored residual or recurrent tumor, despite staged approaches providing mediolateral (transcranial + endonasal) or superoinferior (endonasal + transoral) breadth. There was no benefit of proton-based over photon-based radiation, contradicting conventional presumptions.