Role of chemotherapy in patients with nasopharynx carcinoma treated with radiotherapy (MAC-NPC): an updated individual patient data network meta-analysis

Abstract

Background: The meta-analysis of chemotherapy for nasopharynx carcinoma (MAC-NPC) collaborative group previously showed that the addition of adjuvant chemotherapy to concomitant chemoradiotherapy had the highest survival benefit of the studied treatment regimens in nasopharyngeal carcinoma. Due to the publication of new trials on induction chemotherapy, we updated the network meta-analysis.

Methods: For this individual patient data network meta-analysis, trials of radiotherapy with or without chemotherapy in patients with non-metastatic nasopharyngeal carcinoma that completed accrual before Dec 31, 2016, were identified and updated individual patient data were obtained. Both general databases (eg, PubMed and Web of Science) and Chinese medical literature databases were searched. Overall survival was the primary endpoint. A frequentist network meta-analysis approach with a two-step random effect stratified by trial based on hazard ratio Peto estimator was used. Global Cochran Q statistic was used to assess homogeneity and consistency, and p score to rank treatments, with higher scores indicating higher benefit therapies. Treatments were grouped into the following categories: radiotherapy alone, induction chemotherapy followed by radiotherapy, induction chemotherapy without taxanes followed by chemoradiotherapy, induction chemotherapy with taxanes followed by chemoradiotherapy, chemoradiotherapy, chemoradiotherapy followed by adjuvant chemotherapy, and radiotherapy followed by adjuvant chemotherapy. This study is registered with PROSPERO, CRD42016042524.

Findings: The network comprised 28 trials and included 8214 patients (6133 [74·7%] were men, 2073 [25·2%] were women, and eight [0·1%] had missing data) enrolled between Jan 1, 1988, and Dec 31, 2016. Median follow-up was 7·6 years (IQR 6·2-13·3). There was no evidence of heterogeneity (p=0·18), and inconsistency was borderline (p=0·10). The three treatments with the highest benefit for overall survival were induction chemotherapy with taxanes followed by chemoradiotherapy (hazard ratio 0·75; 95% CI 0·59-0·96; p score 92%), induction chemotherapy without taxanes followed by chemoradiotherapy (0·81; 0·69-0·95; p score 87%), and chemoradiotherapy followed by adjuvant chemotherapy (0·88; 0·75-1·04; p score 72%), compared with concomitant chemoradiotherapy (p score 46%).

Interpretation: The inclusion of new trials modified the conclusion of the previous network meta-analysis. In this updated network meta-analysis, the addition of either induction chemotherapy or adjuvant chemotherapy to chemoradiotherapy improved overall survival over chemoradiotherapy alone in nasopharyngeal carcinoma.

Funding: Institut National du Cancer and Ligue Nationale Contre le Cancer.