Induction Chemotherapy and Sequential Concomitant Chemo-radiation in Locally Advanced Head and Neck Cancers: How Induction-phase Intensity and Treatment Breaks May Impact on Clinical Outcomes.

The purpose of the study was to assess outcomes of locally advanced head and neck (LAHNC) treated with induction chemotherapy (ICT) and subsequent concurrent chemo-radiation.A total of 71 LAHNC patients were treated with 2-3 cycles of docetaxel, cisplatin and 5-fluorouracil as induction chemotherapy and subsequent concurrent chemoradiation with weekly cisplatin or carboplatin. Definitive radiotherapy was delivered with intensity-modulated radiation and a simultaneous integrated boost approach up to a total dose of 70 Gy in 35 fractions to the macroscopic primary and nodal disease.Actuarial 2-year OS, CSS, DFS, MFS, LC were 55.3% (95%CI=39.3-68.6), 58.6% (95%CI=41.9-72), 60.5% (95%CI=47.3-71.4), 87.3% (95%CI=76.2-93.5) and 74.7% (95%CI=61.5-83.9), respectively. On multivariate analysis undergoing to 3 vs. 2 cycles of TPF (HR=22.31; 95%CI=2.68-185.66; p=0.004) and radiotherapy treatment break >4 days (HR=1.28; 95%CI=1.06-1.55; p=0.01) negatively affected cancer-specific survival (CSS) with statistical significance. Achieving complete remission after ICT had a statistically significant impact on CSS (HR=0.9; 95%CI=0.01-0.54; p=0.009). Patients undergoing ICT with 3 cycles had more frequently treatment breaks compared to those submitted to 2 cycles (HR=1.36; 95%CI=1.06-1.73; p=0.01), and had statistically significant longer treatment break time (5.9+1.8 vs. 3+0.36; p=0.02).A shorter ICT phase may be a better option enhancing patients' tolerance during concurrent chemoradiation and affecting clinical outcomes.