Prognostic implications across histological subtypes of head and neck squamous cell carcinoma: An update

Background: Head and neck squamous cell carcinoma (HNSCC) is one of the most common malignancies worldwide, arising from the mucosal epithelium of the oral cavity, oropharynx, hypopharynx, nasopharynx, larynx, and sinuses. In addition to the conventional morphologic pattern characterized by the degree of cellular atypia and squamous differentiation, HNSCC is classified into eight histopathologic subtypes: basaloid, spindle cell, adenosquamous, cuniculatum, verrucous, lymphoepithelial, papillary, and acantholytic. Methods: This review provides a comprehensive review of the literature on the prognostic implications of the histological subtypes of HNSCC. Results: Although there is extensive literature on HNSCC, few studies specifically focus on the treatment and prognosis of its histopathologic subtypes. Among these subtypes, verrucous squamous cell carcinoma and carcinoma cuniculatum generally have a favorable prognosis, while others, such as basaloid and spindle cell squamous cell carcinoma, tend to follow a more aggressive clinical course. Conclusion: In this review, we delve into the histopathological subtypes of HNSCC and explore their clinicopathological, molecular, and prognostic findings. Further molecular investigations aimed at identifying targeted therapies for these subtypes are necessary. Moreover, it is crucial to recognize the emerging histopathological variants documented in the literature, considering the ongoing limitations in prognostic assessment. (c) 2024 Elsevier Masson SAS. All rights are reserved, including those for text and data mining, AI training, and similar technologies.