Tumors of the paranasal
sinus cavities grow silently for months. They are rare lesions,
which usually present late in the course of disease.
Diagnosis is complicated because these lesions symptomatic only
when erosion into adjacent structures occurs. In addition, the symptoms
are identical to those of benign sinonasal disease which delays
definitive diagnosis.
In patients with a history of exposure to known paranasal sinus
carcinogens, it is important for otolaryngologists to keep a high
index of suspicion when treating patients with sinonasal symptoms.
Suspicious lesions should be biopsied and appropriate imaging studies
obtained in order to avoid prolonged delay in definitive diagnosis.
Most lesions are at
an advanced stage at the time of definitive diagnosis. However,
in recent years the widespread use of systematic nasal endoscopy
and high resolution computed tomography have contributed to earlier
diagnosis.
The primary cause of death from paranasal sinus malignancies is
failure of local control. Adequate surgical treatment requires wide
en bloc surgical resection of the tumor and adjacent structures.
The high mortality rate and poor prognosis associated with these
tumors is related to late diagnosis secondary to the early symptomatic
latency of these lesions.
Tumors of the paranasal sinuses are uncommon in the general population.
The incidence of sinonasal carcinoma is about one case per 100,000
people per year, which represents 3% of the upper aerodigestive
tract malignancies and less than 1% of all malignancies in the body.
Males are affected
two to three times more often than females, and most patients are
in their fifth to seventh decade at the time of diagnosis. The majority
of paranasal sinus tumors arise in the maxillary sinus (80%). Twenty
percent arise in the ethmoid sinuses, and the remainder (less than
1%) originate in the frontal and sphenoid sinuses.
Eighty percent of these lesions are squamous cell carcinomas; fifteen
percent are adenocarcinomas, with the remaining five percent composed
of all other types.
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