Abstract
In locally advanced head and neck squamous-cell carcinoma (LA-HNSCC), clinical complete response (cCR) at the primary site, assessed by clinical examination, after induction chemotherapy predicts for a low relapse risk after subsequent chemoradiotherapy. Prior studies showed a cCR rate of 77% with induction nanoparticle albumin-bound (nab)-paclitaxel given with cisplatin and 5-fluorouracil (APF). The primary aims of this non-randomized phase 2 trial were to determine the cCR rate after induction nab-paclitaxel and cisplatin (Arm 1) and after nab-paclitaxel monotherapy (Arm 2). Eligibility required LA-HNSCC, T2-T4 stage classification, and suitable (Arm 1) or unsuitable (Arm 2) candidates for cisplatin. Arm 1 patients received nab-paclitaxel and cisplatin, then cisplatin with radiation. Arm 2 patients received nab-paclitaxel, then cetuximab with radiation. The primary endpoint was cCR after two cycles of induction chemotherapy. Each arm enrolled forty patients. cCR at the primary site occurred in 28 patients (70%) after nab-paclitaxel and cisplatin and in 8 patients (20%) after nab-paclitaxel monotherapy. The overall clinical response rate was 98% after nab-paclitaxel and cisplatin and 90% after nab-paclitaxel monotherapy. In subset analyses, cCR rates by T stage classifications (T2, T3, T4) were 54, 86, and 69% after nab-paclitaxel and cisplatin, and 14, 11, and 26% after nab-paclitaxel. cCR rates by human papillomavirus status (p16 positive oropharynx vs other) were 72 and 64% after nab-paclitaxel and cisplatin and 35 and 9% after nab-paclitaxel. The cCR rate after nab-paclitaxel and cisplatin was similar to APF; however, the cCR rate after nab-paclitaxel monotherapy was lower. The trial was registered at ClinicalTrials.gov NCT02573493 on October 9, 2015.