{Reference Type}: Journal Article {Title}: Induction Chemotherapy for Locoregionally Advanced Sinonasal Squamous Cell Carcinoma and Sinonasal Undifferentiated Carcinoma: A Comprehensive Review. {Author}: Melder KL;Geltzeiler M; {Journal}: Cancers (Basel) {Volume}: 15 {Issue}: 15 {Year}: 2023 Jul 26 {Factor}: 6.575 {DOI}: 10.3390/cancers15153798 {Abstract}: Sinonasal squamous cell carcinoma (SNSCC) and sinonasal undifferentiated carcinoma (SNUC) are two of the most common, high-grade malignancies of the sinonasal cavity. The standard of care for resectable lesions per the National Comprehensive Cancer Network (NCCN) guidelines includes surgical resection with negative margins plus adjuvant radiation therapy. However, surgery for locally advanced disease with both orbital and intracranial involvement is associated with significant morbidity and poor overall survival. Over the last decade, induction chemotherapy (IC) has emerged as part of a multimodal treatment strategy to optimize locoregional disease control and minimize substantial surgical morbidity such as orbital exenteration without compromising rates of overall survival. The response to IC both guides additional therapy and helps prognosticate a patient's disease. This narrative review examines the data surrounding the management of patients with SNSCC and SNUC. The pros and cons of upfront surgical management plus adjuvant therapy will be explored, and the case for IC will be presented. The IC-specific regimens and treatment paradigms for SNSCC and SNUC will each be explored in detail. Organ preservation, treatment morbidity, and survival data will be presented, and evidence-based recommendations will be presented for the management of these patients.