Explore the Value of Adding Induction Chemotherapy to Concurrent Chemoradiotherapy in T3-4N0M0 Nasopharyngeal Carcinoma Patients: A Retrospective Study

Therapeutic Evaluation of Induction Chemotherapy for Locoregionally Advanced Nasopharyngeal Carcinoma With Low-risk N Stage : A Multicenter Retrospective Study From Nonendemic Region of China

OBJECTIVES

The role of induction chemotherapy (IC) remains ambiguous in a patient with T3-4N0-1 nasopharyngeal carcinoma (NPC) according to data from the endemic area of China. Here, we conducted a multicenter retrospective study to investigate the value of adding IC to concurrent chemoradiotherapy (CCRT) for T3-4N0-1 NPC from Northwest China.

METHODS

Data were extracted in 3 hospitals from Northwest China between May 1, 2010 and August 30, 2018. The Kaplan-Meier method was used to estimate the endpoints. Survival curves were compared using the log-rank test. Initial propensity matching was conducted with a 1:1 match of IC + CCRT to CCRT. The primary endpoint of this study was overall survival (OS).

RESULTS

A total of 108 patients with staging T3-4N0-1 were included in this study. The median follow-up time was 50 months (range: 6 to 118 months). IC followed by CCRT did not significantly improve OS compared with CCRT in the whole cohort (89.5% vs 77.6%, hazard ratio: 0.41, 95% CI: 0.16-1.04, P = 0.100). But significantly better OS was found when a well-balanced propensity score-matched cohort was analyzed. Adjusted 4-year OS was 89.5% for IC followed by CCRT versus 71.1% for CCRT (hazard ratio: 0.30, 95% CI: 0.11-0.80, P = 0.027). No significant differences were detected in side effects between the two groups.

CONCLUSION

This study suggested IC followed by CCRT had the potential to further improve OS in patients with T3-4N0-1M0 NPC from Northwest China compared with CCRT. However, prospective studies with a large sample are warranted to confirm the results.

A nomogram to predict survival and guide individualized induction chemotherapy in T3-4N1M0 nasopharyngeal carcinoma

Induction chemotherapy (IC) plus concurrent chemoradiotherapy (CCRT) and CCRT alone were the optional treatment regimens for T3-4N1M0 nasopharyngeal carcinoma (NPC) patients. Therefore, we established a nomogram to predict clinical prognosis and guide individualized IC in T3-4N1M0 NPC. Overall, 699 T3-4N1M0 NPC patients treated with CCRT with or without IC between January 2010 and December 2018 were examined. Overall survival (OS) was the main endpoint. A nomogram was developed that included prognostic variables selected by multivariable analysis. The risk score, which was calculated according to the nomogram, was used for risk stratification. The survival difference of patients undergoing CCRT with or without IC was then compared in risk-stratified subgroups. The nomogram yielded C-indexes of 0.708 (95% confidence interval [CI]: 0.682-0.734) in the training cohort and 0.670 (95% CI: 0.625-0.715) in the validation cohort. Calibration curves for 1-, 3- and 5-year OS suggested a good association between the nomogram predicted and observed probabilities. High-risk patients stratified by nomogram benefited from IC (IC + CCRT vs CCRT: 5-year OS: 77.8% vs 58.8%; P = 0.040; 5-year disease-free survival: 75.0% vs 58.2%; P = 0.017), whereas in the low-risk group, the application of IC was associated with worse locoregional recurrence-free survival and distant metastasis-free survival. This nomogram can serve as a reliable model for prognostic prediction and can be used to guide individualized treatment of T3-4N1M0 NPC. High-risk patients are candidates for IC before CCRT, while the use of IC for low-risk patients should be considered carefully.

A Nomogram to Identify the Optimal Candidates for Induction Chemotherapy in Advanced N-Stage Nasopharyngeal Carcinoma

Purpose

We aimed to select optimal candidates benefiting from the addition of induction chemotherapy (IC) to concurrent chemoradiotherapy (CCRT) in advanced N-stage nasopharyngeal carcinoma (NPC).

Patients and Methods

A total of 624 NPC patients with N2-3 stage received CCRT with or without IC were retrospectively reviewed. We constructed a nomogram for predicting overall survival (OS) based on the result of the multivariate analysis in the training cohort (n = 468) and then tested it on the validation cohort (n = 156). Harrell’s concordance indices (C-index) and time-independent receiver operating characteristic (tdROC) analysis were applied to evaluate the discriminatory ability of the nomogram and compare it with TNM staging. IC plus CCRT was compared with CCRT in the whole cohort and two risk groups based on the nomogram with balanced baseline characteristics. In addition, acute toxicities were compared between different treatment groups.

Results

The nomogram showed good prognostic accuracy with a C-index of 0.716 (95% CI 0.669–0.763) in the validation cohort. The 5-year OS of low and high-risk groups stratified by the nomogram were significantly different. IC+CCRT was significantly associated with superior OS as compared with CCRT (75.4 vs 52.6%, p = 0.009) in the high-risk group. However, no significant difference between IC plus CCRT and CCRT was observed (p = 0.843) in the low-risk group. IC plus CCRT was associated with more grade 1–4 acute toxicities.

Conclusion

Our study can help clinicians select NPC patients with advanced N stage who benefit from IC.