Prognostic factors and nomogram to predict the relapse-free survival of cervical chordoma / 中华骨科杂志

ABSTRACT

Objective:To explore the relevant prognostic factors and construct a nomogram to predict the relapse-free survival of cervical chordoma.Methods:Data of 48 patients with cervical chordoma treated by operation from November 1994 to June 2018 were retrospectively analyzed, including 28 males and 20 females, aged 48.5±15.4 years (range 5-70 years). Data extraction comprised patients age, gender, Karnofsky performance status scale (KPS), duration of preoperative symptoms, location, involved segments, preoperative Frankel score, diagnostic biopsy method, adjuvant radiotherapy, surgical option and complications. Follow-up was conducted at 3, 6, 12 months after surgery and annually, X-Ray/CT/MRI were used to evaluate the progress of disease. Univariate analysis was performed using Kaplan-Meier survival analysis and Log Rank test to identify prognostic factors relevant to relapse-free survival, and multivariate Cox regression analysis was used in multivariate analysis, then R 3.6.2 was used to construct a nomogram.Results:Mean follow-up time was 66.6±51.1 months (range 14-228 months), 35 cases relapsed up to follow-up time, the cumulative 1-year, 3-year and 5-year relapse-free survival were 70.8%, 42.1% and 30.9%. Univariate analysis showed that diagnostic biopsy method ( P=0.016), adjuvant radiation therapy ( P=0.027), surgical option ( P<0.001) were relevant to relapse-free survival of cervical chordoma. Multivariate Cox regression analysis showed that surgical option (intralesional resection after extracapsular separation vs. directly intralesional resection), HR=0.209, 95% CI (0.076, 0.575) had significant impacts on relapse-free survival of cervical chordoma. A nomogram with c-index of 0.760 to predict 1-year, 3-year and 5-year relapse-free survival was conducted basing on age, gender, location, involved segments, diagnostic biopsy method, adjuvant radiation therapy, surgical option. Conclusion:Aspiration biopsy, intralesional resection after extracapsular separation and adjuvant radiation therapy could prolong the relapse-free survival of cervical chordoma. The nomogram in this study could predict 1-year, 3-year and 5-year relapse-free survival of cervical chordoma with relatively good accuracy.