Nasal and paranasal sinus cancer (NPSC) describes malignancies that arise in the nasal cavity and the four pairs of air-filled spaces surrounding it, known as the paranasal sinuses. The nasal cavity is the space behind the nose that connects to the throat. The sinuses include the maxillary, ethmoid, frontal, and sphenoid sinuses. NPSC is widely recognized as a rare disease, accounting for a very small fraction of all cancers diagnosed annually.
Statistical Reality of Nasal Cancer
Cancers affecting the nasal cavity and paranasal sinuses are uncommon malignancies. The incidence rate generally falls below two cases per 100,000 persons per year. In the U.S., only about 2,000 new cases are diagnosed annually, underscoring its scarcity. NPSC accounts for less than one percent of all cancers and roughly three to five percent of all head and neck cancers. Men are generally twice as likely to develop this cancer compared to women, and most diagnoses occur in individuals over the age of 55.
The prognosis for NPSC varies significantly based on the stage at diagnosis. For all stages combined, the five-year relative survival rate in the U.S. is approximately 61%. When the cancer is localized to the original site, the five-year survival rate can be as high as 87%, but this rate drops considerably once the cancer has spread to distant parts of the body.
Understanding the Different Types of Nasal Cancer
Nasal and paranasal sinus cancers are classified based on the type of cell from which they originate within the nasal and sinus lining.
Squamous Cell Carcinoma (SCC)
The most frequent pathological type is Squamous Cell Carcinoma (SCC), which develops from the flat, thin cells lining the nasal cavity and sinuses. SCC accounts for about half of all sinonasal malignancies.
Adenocarcinoma
Adenocarcinoma is the second most common type, arising from the gland cells that produce mucus.
Other Rare Types
A less frequent type is Esthesioneuroblastoma, or olfactory neuroblastoma, which originates from the neuroepithelial cells responsible for the sense of smell. This tumor can occur across a wide age range. Sinonasal Undifferentiated Carcinoma (SNUC) represents a very rare and highly aggressive subtype. SNUC is characterized by rapid growth, often leading to a poor prognosis due to its advanced stage upon initial presentation.
Primary Risk Factors and Exposure
The development of NPSC is strongly linked to chronic exposure to specific inhaled substances, particularly in occupational settings. Exposure to hardwood dust, such as that generated in furniture manufacturing or carpentry, is a well-established risk factor, especially for adenocarcinoma. Other implicated materials include leather dust, nickel compounds, and chromium compounds, which affect workers in industries like shoemaking and metal refining.
Lifestyle factors also contribute to risk, with long-term cigarette smoking being a recognized cause, primarily for the squamous cell subtype. Smoking introduces nitrosamines and other cancer-causing chemicals that can irritate the nasal lining. Infection with the Human Papillomavirus (HPV) is considered a biological risk factor. High-risk HPV types are found in approximately 25% to 30% of sinonasal squamous cell carcinomas, suggesting a role in the development of this specific cancer subtype.
Recognizing Common Symptoms
The earliest symptoms of nasal and paranasal sinus cancer often resemble common, non-cancerous conditions like allergies or a persistent sinus infection. This similarity contributes to delayed diagnosis. The most frequent initial signs are persistent nasal obstruction or congestion that does not improve with standard treatments.
A significant differentiator is the unilateral nature of the symptoms, meaning the blockage or pain affects only one side of the nose or face. Patients may also experience recurrent nosebleeds (epistaxis) or a gradual loss of the sense of smell. As the tumor grows, it can cause facial pain, pressure, or numbness, and advanced tumors may cause vision changes if they extend into the eye socket.