Long-term outcomes of neoadjuvant chemotherapy followed by concurrent chemoradiotherapy (CCRT) vs CCRT alone for nasopharyngeal carcinoma in the era of intensity-modulated radiation therapy using propensity score matching method

PURPOSE Whether neoadjuvant chemotherapy (NCT) followed by concurrent chemoradiotherapy (CCRT) could improve survival in nasopharyngeal carcinoma (NPC) remains controversial especially in the era of intensity-modulated radiation therapy (IMRT), and we explored the role of NCT for NPC patients. PATIENTS AND METHODS A retrospective review was conducted of 255 NPC patients treated with NCT+CCRT (n=67) or CCRT alone (n=188) based on IMRT between December 2006 and December 2012. To control the imbalance, a 1:2 match was performed using propensity score matching (PSM) method based on patient's heterogeneity and regimens of concurrent chemotherapy (CCT). The long-term treatment outcomes and toxicity between NCT group (n=67) and concurrent chemoradiotherapy (CRT) group (n=134) after PSM were compared. RESULTS The 5-year overall survival (OS), progression-free survival (PFS), recurrence-free survival (RFS), local recurrence-free survival (LRFS), regional recurrence-free survival (RRFS) and distant failure-free survival (DFFS) were 78.8%, 69.1%, 90.0%, 90.0%, 100% and 78.3% for NCT group, while 79.5%, 75.7%, 92.7%, 94.2%, 96.1% and 82.7% for CRT group (P=0.305, 0.448, 0.790, 0.512, 0.104 and 0.671). It indicated that the treatment method (NCT+CCRT vs CCRT) was not the independent prognostic factor for the survival in NPC patients, and only patients who had completed at least two cycles of CCT got better OS, RFS and DFFS (P=0.009, 0.016 and 0.043), whether to receive NCT or not. No difference in the incidences of any acute and most late toxicity between the two groups was shown. CONCLUSION Our study did not show the exact advantage of NCT followed by CCRT compared with CCRT alone or higher incidences of toxicity in NCT group. It suggests that NCT might not be necessary if two or more cycles of CCT are finished well in the era of IMRT, and when NCT is finished well, less than two cycles of CCT with IMRT could be enough. However, in the era of IMRT, the role of NCT still needs to be further explored.