Paranasal sinus malignancies comprise a diverse group of histologies, accounting for approximately 3% of upper aerodigestive tract malignancies. Most malignancies are diagnosed within the 5th and 6th decades of life, are more prominent in Caucasians, and disproportionally affect men twice as often as women. Malignancies of the paranasal sinuses frequently present at more advanced stages, as compared to cancers of the nasal cavity. This has been attributed to the fact that lesions in these cavities, particularly the maxillary sinuses, can grow inconsequentially for longer periods of time before producing symptoms. Overall five-year relative survival for all types of sinonasal malignancies is poor at approximately 50%, although this greatly depends on the histology involved and the primary site of origination.

Squamous cell carcinoma is the most commonly involved epithelial malignancy, followed by adenocarcinoma, mucosal melanoma, esthesioneuroblastoma, adenoid cystic carcinoma, and sinonasal undifferentiated carcinoma (SNUC).  For lymphomas, diffuse large cell B cell lymphoma is most common, followed by nasal NK/T cell lymphoma.  Leather, nickel, and wood dust have been associated with the development of adenocarcinoma, whereas squamous cell carcinoma is more frequently associated with tobacco and alcohol abusers. In general, the maxillary sinus cavities are the most commonly involved paranasal subsite, followed by the ethmoid, sphenoid, and frontal sinuses. 

Epithelial malignancies of the nasal cavity, maxillary and ethmoid sinuses are staged by the TNM staging criteria as outlined by the American Joint Committee on Cancer (AJCC).  Malignancies of the sphenoid and frontal sinuses are so rare that no set staging system is currently in place for these primary sites.  Lymph node involvement and distant metastasis are generally rare in sinonasal tumors, but portend poorer prognoses when present.  Some differences in staging are notable for particular histologies. As per the AJCC 7th edition, mucosal melanomas are all considered advanced stage, regardless of regional or distant metastasis. Esthesioneuroblastomas and SNUC tumors are typically staged by Hyams or Kadish staging systems.  Staging for lymphomas are classified with the Lugano system (based on the Ann Arbor system).  Treatment for paranasal sinus malignancies (non-lymphomas) consists of primary surgical therapy, with or without radiotherapy.  Treatment for lymphomas primarily consists of chemotherapy and radiation therapy.