Risk models to predict the recurrence of major salivary gland malignancies after surgery assist clinicians in appropriately selecting candidates for adjuvant treatment. This study aimed to externally validate the MSKCC nomogram based on an Asian cohort.
We retrospectively enrolled 149 patients who had undergone intended curative resections for major salivary gland carcinoma between 2007 and 2012. Clinicopathological parameters and long-term outcomes of our cohort were analyzed. The performance of the MSKCC nomogram and American Joint Committee on Cancer (AJCC) 7th staging system in predicting recurrence-free survival (RFS) was compared.
Univariate analysis followed by multivariate adjustment identified histological grading, vascular invasion, and perineural invasion as three independent prognostic factors predictive of disease recurrence. The calibration plot indicated that the MSKCC nomogram accurately estimated the recurrence in low-risk groups but tended to overestimate the recurrence in high-risk groups, compared to the actual observed events. The power to predict the 5-year recurrence-free probability did not differ between the MSKCC nomogram and the AJCC system (c-index, 0.82 vs. 0.77, p = 0.45). Importantly, when the MSKCC nomogram was combined with the AJCC system to predict the 5-year recurrence-free probability, their c-indices were 0.92, 0.90, 0.51, and 0.62 for the patients categorized with AJCC stage I, II, III, and Iva disease, respectively.
Although the MSKCC nomogram and AJCC staging system exhibited comparable performances in predicting recurrence risk, concurrent use of the MSKCC nomogram enabled identification of high-risk patients that were identified as having early stage disease by the AJCC system.
Clinical trial identification
All authors have declared no conflicts of interest.