The current state of sinonasal malignancies and recent management updates

Cancers of the sinonasal tract represent a broad, heterogeneous group of tumors that can present significant diagnostic challenges for the surgical pathologist as well as management issues for the treating otolaryngology clinician. Greater than 60% of sinonasal malignancies are squamous cell carcinomas, and patients have an average 5‐year overall survival rate of 50%. Sinonasal adenocarcinoma and olfactory neuroblastoma are among the cancers with the best prognosis, with 67% and 62% 5‐year overall survival rates, respectively. The fifth edition of the World Health Organization Classification of Head and Neck Tumours (2022) recognizes at least 10 types of primary sinonasal cancer (Table 1) in addition to other infrequent malignant neoplasms not specific to the sinonasal cavity, such as rhabdomyosarcoma, Ewing sarcoma, and diffuse large B‐cell lymphoma among others. In some cases, such as olfactory neuroblastoma, sinonasal undifferentiated carcinoma (SNUC), sinonasal neuroendocrine carcinoma, and mucosal melanoma, sinonasal cancers will metastasize to regional lymph nodes or to distant sites, where they may be sampled by fine‐needle aspiration (FNA). The cytologic evaluation and diagnosis of this rare heterogeneous group of malignancies can be challenging, and a general familiarity by cytologists and practicing pathologists with the spectrum of sinonasal malignancies and their management is useful. In this commentary, we review the recent article by Thawani et al., which summarizes the current management approaches to the most common sinonasal malignancies. The recent report by Thawani et al. highlights updates in the molecular profiles, prognosis, and clinical management of selected sinonasal malignancies, focusing on cancers specific to the sinonasal tract as well as some occurring in the head and neck and often involving the sinonasal tract. Thawani et al. expand upon the available approaches to management for sinonasal cancers compared with the current National Comprehensive Cancer Network guidelines. A shared feature between the two management approaches is the use of fewer treatment branch points compared with corresponding tumor types, as published in the fifth edition of the World Health Organization Classification of Tumours of the Head and Neck. For example, the sections on sinonasal squamous cell carcinoma and sinonasal adenocarcinoma do not distinguish between keratinizing and nonkeratinizing types (or between human papillomavirus‐ associated and human papillomavirus‐independent types) for the former or between intestinal and nonintestinal types for the latter, although there are differences in the histopathologic features and/or prognosis for these sinonasal cancers. In addition, SWI/SNF‐complex–deficient carcinomas (including SMARCB1‐deficient sinonasal carcinomas) are included briefly when discussing the highly aggressive SNUC. This reflects data that the authors present from currently available treatment options and clinical trials. It is not surprising that the management approaches for the most common sinonasal cancers as presented by Thawani et al. contrast with the more granular diagnostic approach used by pathologists, which includes not only the more common cancer types but also rare tumor subtypes. In this regard, the role of pathology in continually analyzing and refining tumor classification is extremely important for advancing the field of oncology and, most importantly, for driving advances in patient care. The pathology literature includes many reports about the morphologic and biologic subtypes of sinonasal cancers with the intent of ensuring appropriate classification and prognostication as well as the possibility that such classification will have either present or future implications for management. In this way, clinical management algorithms often lag behind the ability of pathologists to subtype cancers, and this is especially true for rare cancers. One example to address this would be the recent ongoing shift toward the so‐called basket or umbrella clinical trials. Such a framework offers advantages, including the ability to advance treatment for some rare tumors that would otherwise be difficult to study on their own. They recruit and group tumors with a shared driver molecular alteration in a tumor type‐agnostic way. This is particularly relevant for the growing number of sinonasal cancer subtypes with specific genetic alterations, such as IDH2‐mutant SNUCs and SWI/ SNF‐deficient tumors, among others. Multiple clinical trials are now in