Development and Internal Validation of a Prediction Model for Nasopharyngeal Carcinoma: Using BMI and Inflammatory Response for Deciding Sequence of Chemotherapy.

PURPOSE: Concurrent chemoradiotherapy followed by adjuvant chemotherapy (CRT-AC) and induction chemotherapy followed by concurrent chemoradiotherapy (IC-CRT) are among the best treatments in nasopharyngeal carcinoma (NPC). This study aimed to develop a model for deciding the sequence of chemotherapy in NPC. METHODS: Data were separated into two cohorts. The CRT-AC cohort had 295 patients, while the IC-CRT cohort had 112. The predictors were standard factors with BMI and neutrophil-lymphocyte ratio (NLR) to predict overall survival (OS). A flexible parametric survival model was used. RESULTS: A total of 132 (44.7%) and 72 patients (64.3%) died in the CRT-AC and IC-CRT cohorts, respectively. The predictors in the final models were age, sex, T, N, NLR, and BMI. The models of OS for CRT-AC and IC-CRT had concordance indices of 0.689 and 0.712, respectively, with good calibration curves. When changing the burden of disease along with NLR and BMI, we found that CRT-AC was not significantly different OS from IC-CRT when low NLR (<3) and high burden of disease (T3N3). By contrast, CRT-AC was remarkably more effective when there were high levels of NLR (≥3) and BMI (≥25) with any burden of disease (anyT anyN). CONCLUSION: With additional BMI and NLR in model, it could be easier to decide between CRT-AC and IC-CRT in countries with limited health care resources.

Added value of metastatic cervical lymph node group V in nodal staging of nasopharyngeal cancer.

BACKGROUND: Prognostic significance of posterior cervical lymph node metastasis in nasopharyngeal cancer is largely unknown. This study aims to determine the added prognostic significance of cervical lymph node group V to the standard American Joint Committee on Cancer (AJCC) staging system (eighth edition AJCC) of nasopharyngeal patients with cancer treated with intensity-modulated radiation therapy (IMRT) in terms of overall survival (OS), distant metastatic-free survival (DMFS), and disease-free survival (DFS). METHODS AND MATERIALS: A retrospective cohort of 199 consecutively diagnosed nasopharyngeal patients with cancer treated with definitive radiotherapy (RT) or concurrent chemoradiotherapy (CCRT) in the era of IMRT in a large university hospital in endemic area of Southeast Asia. Pre-treatment imaging studies were thoroughly re-evaluated and re-staged by a board-certified radiologist using radiographic criteria for cervical lymph node metastasis. T and N classifications were reclassified according to the eighth AJCC staging system. Group V (Va and Vb) cervical node was evaluated for its added prognostic significance. Cox's proportional hazard model was used to retrieve hazard ratio (HR), 95% confidence interval and P value for N classification. Harrell's C-statistic (concordance index) was used for test of discrimination and internal validation was calculated by bootstrap method. RESULTS: This study demonstrated greater separation of OS with HR of 6.75 (95%CI 1.94-23.51, P = .003) by using group Vb only as N3 compared to HR of 4.70 (95%CI 1.37-16.13, P = .014) by using current standard N3 disease (groups IV and Vb). Similarly, N2 with presence of Va shows worsened DFS with HR of 8.70 (95%CI 1.08-69.67, P = .042) compared to N2 without Va with HR of 5.93 (95%CI 0.76-46.00, P = .089). After incorporating cervical group V into nodal staging, the HR and 95%CI among each group was better separated than the eighth AJCC staging system but without significant improvement in C-index. CONCLUSION: Cervical lymph node group V is a potentially added prognostic factor to standard TNM staging.