269MO Comparison of Three Induction Chemotherapy Regimens with Gemcitabine Plus Cisplatin, Cisplatin Plus Fluorouracil, and Cisplatin Plus Capecitabine for Locoregionally Advanced Nasopharyngeal Carcinoma: A Pooled Analysis of Two Prospective Studies

We report the results of our prospective study comparing the differences in efficacy and safety between three induction chemotherapy regimens of gemcitabine plus cisplatin (GP), cisplatin plus fluorouracil (PF) and cisplatin plus capecitabine (PX) in previously untreated locoregionally advanced nasopharyngeal carcinoma (NPC). Induction chemotherapy with either GP (from our prospective observational study), PF or PX (from NPC-0501 study) was given in prospectively recruited patients who had previously untreated locoregionally advanced (stage III to IVA) NPC. The primary study objectives included locoregional recurrence-free survival (LRFS), distant metastasis-free survival (DMFS), progression-free survival (PFS), cancer-specific survival (CSS) and overall survival (OS). The secondary objectives were major treatment-related toxicities (grade ≥ 3), both acute and late. From 2006 to 2016, 278 patients were enrolled (84, 94 and 100 patients in GP, PF and PX group respectively). After a median follow-up duration of 80 months, the 3-year LRFS, DMFS, PFS, CSS and OS of the whole population were 84.9%, 80.9%, 78.7%, 89.8% and 88.1% respectively. There were no statistically significant difference in pre-specified survival endpoints between GP, PF and PX group in both stage III and stage IVA patients. GP group had a lower incidence of severe (grade 3 or 4) anaemia and diarrhoea in stage III patients; and severe anaemia, dehydration, renal impairment and vomiting in stage IVA patients. The incidences of grade 3 or 4 late toxic effects were similar between 3 induction regimen groups. GP had similar efficacy and potentially fewer complications as compared with PF and PX.