ESTRO meets Asia 2024 - Abstract Book

S180

Interdisciplinary – Head & neck

ESTRO meets Asia 2024

275

Digital Poster

A nomogram based on PET/CT signatures to predict early metastasis in nasopharyngeal carcinoma patients

mengting xu

Head and neck radiotherapy Department, Fujian Cancer Hospital, Fuzhou, China

Purpose/Objective:

This study aimed to construct a novel nomogram based on PET/CT signatures to predict early metastasis (EM) in patients with nasopharyngeal carcinoma (NPC) .

Material/Methods:

A total of 473 NPC patients with PET/CT in our institute were enrolled in this study to be the training cohorts and 222 NPC patients with PET/CT in the Second Attached Hospital of Fujian Medical University and the First Affiliated Hospital of Xiamen University were enrolled to be the validation cohorts. The independent prognostic factors were determined by univariate and multivariate logistical regressions. The patients were stratified into different risk groups by nomogram model. The ROC analysis was used to compare models and other risks. A decision curve analysis (DCA), calibration curve, the kernel plot and clinical utility curves (CUCs) were applied to verify the predictability of nomogram model.

Results:

In total, 63 (13.3%) and 22 (9.9%) patients in training and validation cohorts were diagnosed with EM. Prognostic factors including T stage, N stage, SUVmax- N/T and Pretreatment plasma EBV DNA and neutrophil-to-lymphocyte ratio (NLR) were recognized as the independent risk factors, which finally separated the patients into low- and high-risk groups. The AUC of the nomogram was significantly excellent to every single independent factor (0.853, 95%CI: 0.805-0.901, P<0.001) and (0.898, 95%CI: 0.837-0.960, P<0.001) in the training and validation cohorts, respectively. The DCA of the nomogram model was superior to any others in any threshold probability. 0.31 was selected as optimal threshold probability according to the CUCs and the kernel plot for clinical decision-making. About 90% non-EM and 48% EM patients could be distinguished by it.

Conclusion:

Our nomogram model incorporating PET/CT indicators could serve as an accurate and powerful tool for the prediction of EM of NPC , thus we can select a personalized treatment, suitable treatment duration, and increased follow-up frequency.

Keywords: Nasopharyngeal carcinoma, early metastasis