BackgroundNeoadjuvant chemotherapy for induction selection of definitive treatment (IS) protocols have shown excellent outcomes for organ preservation and survival in patients with T3 laryngeal squamous cell carcinoma (LSCC). We seek to evaluate survival and organ preservation outcomes in T4 LSCC patients treated with IS protocols. MethodsRetrospective cohort of advanced T3 and T4 LSCC patients who underwent IS protocols based upon potential for preserving a functional larynx. Patients received one neoadjuvant cycle of platinum-based chemotherapy with either 5-fluorouracil or docetaxel or with two cycles of platinum-based chemotherapy with docetaxel and a Bcl-2 inhibitor. Patients who achieved ≥ 50 % response as determined by radiographic review and/or endoscopic evaluation received definitive chemoradiation. Patients who had < 50 % response after IS underwent total laryngectomy (TL) followed by post-operative radiation +/- chemotherapy. ResultsAmongst T4 patients, 114 met inclusion criteria including 89 who underwent IS protocols and 25 who received an upfront TL. In total, 76.0 % of T3 patients and 71.9 % of T4 patients responded to IS and underwent definitive chemoradiation. There was no significant difference in hazard of death between T4 IS and T4 TL patients (HR: 0.9, p = 0.86). Among responders, there was no significant difference in 5-year laryngectomy-free survival (T3 – 59.6 %, T4 44.3 %, p = 0.15) or laryngeal preservation by T stage (T3 – 72.8 %, T4 – 73.0 %, p = 0.84). ConclusionsSelect T4 patients may benefit from organ preservation using IS protocols with similar response rates to patients with T3 tumors, without compromising survival when compared to upfront TL.