MRI-based assessment of tumor aggressiveness in nasopharyngeal carcinoma: risk stratification and survival prediction.

Abstract

Objectives: MRI can reveal the signal characteristics and invasive potential of tumors. Our study aimed to explore the potential of MRI-identified primary tumor aggressiveness-related factors in nasopharyngeal carcinoma (NPC).

Materials and methods: This study retrospectively included patients with NPC from three institutes, and a prospective cohort was also included. A total of 12 imaging factors were evaluated in each patient. Univariate and multivariable Cox analyses were used to explore its predictive value. The model performance was calculated and compared, and Kaplan-Meier curves were used to compare survival outcomes.

Results: This study included 505 patients (mean age, 49.1 years, 384 males; Training cohort: 311; validation cohorts: 74, 68, and 52). Three imaging factors (Radiological depth, Tumor growth type, and Expanded enhancement area) were selected to construct the I-score. The median value of I-score was 8 (interquartile range: 5, 9), and there was no significant difference among the three cohorts (p = 0.866). The performance of the I-score (C-index: 0.693-0.753) was significantly higher than that of the Clinic model (p < 0.05) and TNM stage (p < 0.05). The similar results were found in validation cohorts 1, 2, and 3 (I-score: 0.672-0.752, 0.665-0.719, and 0.676-0.763). The 5-fold cross-validation (iteration = 1000) also showed robust results. The high-risk group identified by I-score had significantly worse survival compared with the low-risk group in four cohorts (all p < 0.05).

Conclusion: Radiological depth, tumor growth type, and expanded enhancement area are crucial factors in the risk stratification for NPC.

Key points: Question Can the MRI features of the primary tumor predict prognosis in patients with nasopharyngeal carcinoma? Findings Critical MRI features of primary tumor, including Radiological depth, Tumor growth type, and expanded enhancement area, serve as significant predictors of long-term survival in nasopharyngeal carcinoma. Clinical relevance In this retrospective study of 505 patients across four independent cohorts, the I-score constructed by Radiological depth, Tumor growth type, and Expanded enhancement area showed high performance in prognosis prediction, potentially supporting individualized therapy decision-making.