Sinonasal Cancers

Clinical, aetiological, pathological, and genetic features differ from tumours at the main head and neck cancer localisations

Owing to distinctive characteristics, sinonasal tumours should be considered as separate entities, not to be included in the miscellany of head and neck cancers. Those are rare tumours, but the clinical management has improved due to advances in imaging techniques, endoscopic surgical approaches, and radiotherapy. A group of clinicians from the Hospital Universitario Central de Asturias in Oviedo, Spain review in the Nature Reviews Clinical Oncology epidemiology of sinonasal tumours, clinical presentation, histology, tumorigenesis, genetic characterisation, models of sinonasal cancer, prognosis and advances in treatment.

The sinonasal cavities represent an anatomical region affected by a variety of tumours with clinical, aetiological, pathological, and genetic features distinct from tumours at the main head and neck cancer localisations. Squamous-cell carcinoma and intestinal-type adenocarcinoma account for 80% of all sinonasal tumours, and are aetiologically associated with professional exposure to wood and leather dust particles and other industrial compounds, and therefore, are officially recognised as an occupational disease.

Patients with sinonasal tumours often present with non-specific clinical symptoms and with advanced-stage tumours, and therefore, have a poor prognosis.

Rare tumours

Sinonasal tumours are rare, with an annual incidence of approximately 1 case per 100,000 inhabitants worldwide, a fact that together with histological diversity have hampered diagnosis, genetic analyses, classification, and staging, and prevented the accumulation of clinical experience at individual institutions. Nevertheless, the clinical management of sinonasal cancer has improved owing to advances in imaging techniques, endoscopic surgical approaches, and precision radiotherapy.

These tumours have aneuploid genomes—harbouring multiple genetic aberrations—that are distinct from each other and from histologically similar tumours, head and neck squamous-cell carcinoma and colorectal adenocarcinoma, respectively. Currently, increasing knowledge of the genomics of sinonasal cancer enables a new approach to tumour classification, which is more-refined than classic anatomical and histological grouping.

Furthermore, genetic analyses comprising at least of a panel of druggable gene products, if not genome-wide, would be a promising addition to open up possibilities for targeted anticancer therapy. A low number of patients with sinonasal tumours who are available for clinical trials might not be an issue, as targeted therapy could be based on the results of ongoing or completed trials in patients with other more-common tumours that have the same druggable genetic aberrations. In addition, in vitro and mouse models of sinonasal tumours have been developed and are now available for preclinical studies with laying the foundations for future targeted therapies.

Occupational exposure to wood and leather dust is a strong aetiological factor, possibly through tumorigenic pathways of chronic inflammation. Further investigation of this field is needed and might yield tools for chemoprevention, such as anti-inflammatory drugs, and for early detection of tumours in individuals at risk. In the case of squamous-cell carcinoma, routine HPV-testing in biopsies of patients with inverted papilloma might also be advisable.

To provide the best possible care, the authors advocate that patients with sinonasal cancer should be treated in clinical referral centres specialised in skull-base pathologies. The study of molecular tumorigenic pathways and the testing of alternative treatment strategies would greatly benefit from wider multi-institutional collaboration.

Future directions

As technology improves, robot-assisted surgery might be the next breakthrough in sinus and skull-base surgery. With increasing miniaturisation of instrumentation to fit the sinonasal area and skull base, imaging-guided, robot-assisted surgery will become more useful, less invasive, and more precise.

Improved radiation therapy techniques, such as proton-beam and light ions radiotherapy, could potentially reduce toxicity and achieve better quality-of-life, and might improve survival outcomes compared with the current standard methodologies; these possibilities might be especially relevant in patients with tumours that have dural involvement or that affect structures such as the optic nerves and/or chiasm, cavernous sinus, or carotid artery.

The development of novel approaches to systemic therapy alone or in combination with other therapeutic modalities might contribute to improve disease control and minimise the associated morbidity if vital organs are affected.

The full article is accessible through myESMO Journals programme.

Reference

Llorente JL, López F, Suárez C, et al. Sinonasal carcinoma: clinical, pathological, genetic and therapeutic advances. Nat Rev Clin Oncol 2014; Published online 17 June. doi:10.1038/nrclinonc.2014.97