Malignancies can form within the nasal cavity and surrounding paranasal sinuses, though they are rare. The inside of the nose is lined with a mucous membrane (mucosa), which differs from sun-exposed skin. Cancers developing internally are generally not the common, UV-related skin cancers, but are classified as sinonasal cancers. These originate from the specialized cells of the respiratory tract lining. Sinonasal tumors account for a very small fraction, typically less than five percent, of all cancers diagnosed in the head and neck region.
Distinguishing Nasal Cavity Cancers
Most malignant tumors found within the nasal cavity and paranasal sinuses are classified based on their cell type of origin, rather than being traditional skin cancers. Squamous Cell Carcinoma (SCC) is the most common type, accounting for over half of all sinonasal malignancies. SCC arises from the flat squamous cells lining the mucosal surface of the nasal passages and sinuses.
Adenocarcinoma is the next most frequent type, developing from glandular cells that produce mucus. Mucosal Melanoma is a less common, but highly aggressive, form that originates from melanocytes in the mucosal lining. Unlike external skin melanoma, mucosal melanoma is not linked to ultraviolet radiation.
These internal cancers are distinct from Basal Cell Carcinoma (BCC), the most common form of skin cancer associated with sun damage. BCC is typically found only on the external nose or the vestibule (the entrance), where sun exposure occurs, and is rarely seen deeper inside. The internal environment can also give rise to rare tumors, such as olfactory neuroblastoma, which stems from nerve cells responsible for smell.
Primary Risk Factors
Since internal nasal cancers are unrelated to sun exposure, primary risk factors involve occupational and environmental exposures affecting the respiratory lining. The inhalation of specific industrial dusts and chemicals is strongly linked to increased risk, particularly for adenocarcinoma.
Recognized hazardous substances include wood dust (common in carpentry), nickel compounds, chromium dust, and certain chemicals used in leather and textile manufacturing. These airborne particles accumulate on the mucosal lining, causing chronic irritation and cellular changes that can lead to malignant transformation.
Tobacco use, including smoking, is an established factor that raises the risk for sinonasal cancers, particularly SCC. Infection with certain high-risk strains of the Human Papillomavirus (HPV) has also been associated with some cases. Chronic inflammation from conditions like persistent sinusitis is considered a potential, though less direct, contributing factor.
Recognizing Symptoms
Early symptoms often mimic common, benign conditions like chronic allergies or sinus infections, making diagnosis challenging. The most frequent sign is persistent nasal obstruction or congestion that fails to clear with standard treatments. Blockage affecting only one side of the nose (unilateral) is particularly concerning.
Other symptoms include unexplained or frequent nosebleeds (epistaxis). As the tumor grows, patients may experience chronic pain or pressure in the facial area, specifically around the nose, cheeks, or eyes. A change in the sense of smell (anosmia) can also occur if the tumor affects the olfactory region.
Advanced symptoms arise when the tumor expands into adjacent structures, such as the orbit or oral cavity. This growth can manifest as a visible lump on the face or roof of the mouth, facial numbness or tingling, or persistent watery eyes. Changes in vision, such as double vision or a bulging eye on one side, indicate pressure on the eye socket and require immediate medical evaluation.
Diagnosis and Medical Approach
Diagnosis begins with a thorough physical examination, including nasal endoscopy. During endoscopy, a physician uses a thin, flexible tube with a camera to visually inspect the nasal passage and sinus openings for abnormal growths. If a suspicious mass is identified, imaging scans are essential to determine the tumor’s exact size and extent of spread into nearby bone or soft tissue.
Computed Tomography (CT) scans and Magnetic Resonance Imaging (MRI) are the preferred methods, providing detailed cross-sectional images of the complex sinonasal anatomy. The definitive diagnosis requires a biopsy, where a small tissue sample is surgically removed and examined by a pathologist. This analysis confirms the presence of cancer and determines the specific cell type, which guides subsequent treatment decisions.
Treatment for nasal cavity and paranasal sinus cancers is highly individualized and often involves a multimodality approach. Surgery is the most common primary treatment, aiming to remove the entire tumor along with a margin of healthy tissue. This is frequently followed by radiation therapy to eliminate remaining cancer cells and reduce recurrence risk. Chemotherapy may be used in combination with radiation, either before or after surgery, depending on the cancer type, stage, and location.