Sinonasal Tumors

1

What are the important epidemiologic aspects of sinonasal cancer?

Sinonasal cancer is rare, accounting for only 3% of upper aerodigestive tract malignancies. There are varied histologic subtypes of sinonasal cancer, which at least in part explains the diverse behavior and presentation of these tumors. Sinonasal malignancies tend to be diagnosed in the fifth and sixth decades of life. The disease is most common in Caucasians, and men are affected at twice the rate of women. A number of occupational exposures are associated with these cancers, including industrial fumes, nickel, leather, and wood dust (more details later in this chapter). There is also a higher rate of sinonasal cancers in cigarette smokers and heavy alcohol users. The 5-year survival for all nasal and paranasal malignancy is 40%, although this varies based on the histopathology of the tumor.

2

What are the most common presenting symptoms of sinonasal tumors? What symptoms are particularly concerning for malignancy?

Unilateral nasal symptoms are the most common presenting symptoms of sinonasal tumors, including obstruction, discharge, congestion, and epistaxis. These symptoms are often overlooked because they can mimic chronic sinusitis or allergies. However, persistent or worsening unilateral nasal symptoms or development of orbital symptoms, such as vision loss, tearing (epiphora), diplopia, or exophthalmos warrant a detailed examination.

Paresthesia or pain along V2 (maxillary nerve), cheek swelling, and numbness of the face or palate would be unusual for sinusitis and are symptoms that are concerning for malignancy. Cavernous sinus invasion by sphenoid tumors can lead to dysfunction of cranial nerves III, IV, V1, V2, and VI. Thus, the most important indicators of malignancy include cranial neuropathies and orbital complications.

3

What are the different types of nasal papillomas?

Nasal papillomas are characterized based on their histologic appearance.

• Exophytic (fungiform) papilloma: the most common subtype, accounting for 50% of nasal papillomas. These papillomas typically arise from the nasal septum and resemble papillomas found at other locations on the body in terms of histopathology. In contrast to the other types of nasal papillomas, the exophytic papilloma does not have malignant potential.

• Inverted (endophytic) papilloma: these arise from Schneiderian mucosa, which is ectodermally derived ciliated columnar epithelium with goblet cells, though it is different from similarly appearing respiratory epithelium, which is endodermally derived. These papillomas are most commonly located on the lateral nasal wall or maxillary sinus; however, any paranasal sinus can be involved ( Fig. 19.1 ). These papillomas account for 47% of nasal papillomas and are associated with high rates of recurrence if not completely resected. Inverted papillomas are associated with an 8% to 10% chance of malignant transformation to squamous cell carcinoma. Inverted papillomas can be associated with HPV infection.

  

• Oncocytic (cylindrical) papilloma: oncocytic papillomas usually arise from the lateral nasal wall and are the rarest of the three papilloma types, accounting for only 3% of nasal papillomas. These tumors are thought to have rare malignant potential, usually reported at between 4% and 17% ( Fig. 19.1 ).

4

What is the standard treatment for inverting papilloma?

Complete surgical resection with clear margins is the treatment of choice for all sinonasal papillomas. Identification and removal of the tumor site of attachment (origin) gives the highest chance of cure. Radiation with or without chemotherapy is reserved for tumors with malignant transformation.

Traditional open surgery utilizes a lateral rhinotomy or midface degloving to provide access to the nasal cavity for tumor removal. Endoscopic or endoscopic-assisted approaches have largely replaced open approaches for most IPs and have reduced the tumor recurrence rate from 20% to 12%.

5

What is a juvenile nasopharyngeal angiofibroma (JNA)?

JNA is a benign vascular tumor, seen exclusively in adolescent males. These tumors are slow growing, are locally invasive, and do not metastasize. However, these tumors can be quite large at presentation and can involve the intracranial cavity, orbit, pterygopalatine fossa, or infratemporal fossa. JNAs often present with unilateral, recurrent epistaxis. CT/MRI adding angiography can be helpful to visualize the vascularity of the tumor and confirm the diagnosis. Biopsy carries a high risk of hemorrhage and is not recommended, and preoperative embolization is often warranted to reduce intraoperative blood loss.

6

What is Fisch’s classification system for JNA?

• Fisch I: limited to nasal cavity

• Fisch II: extends to pterygomaxillary fossa or sinuses with bony destruction

• Fisch III: invades orbit, infratemporal fossa, or parasellar area

• Fisch IV: extends to cavernous sinus, optic chiasm, or pituitary fossa

7

What is the treatment of JNA?

Tumors are typically embolized prior to surgical removal to reduce intraoperative bleeding. Endoscopic techniques are typically used for Fisch I and II, whereas more advanced lesions may require a craniofacial or endoscopic-assisted resection. Radiation therapy may be used for unresectable tumors.

8

What other benign tumors are found in the nasal cavity? What are the unique features of these tumors?

• Osteomas are the most common benign sinonasal tumors and are slow-growing tumors of mature bone. Multiple osteomas can be associated with Gardner’s syndrome. These are most often incidentally discovered on CT scans of the sinus, although they can cause symptoms by obstruction of normal sinus drainage or through direct mass effect. The most common location of osteomas in the paranasal sinuses is in the frontal sinuses, with more than 80% presenting in this location.

• Hemangiomas are rare and most often present on the septum or inferior turbinate.

• Pyogenic granulomas are benign, friable polypoid lesions often found on the septum that can be caused by irritation, physical trauma, and hormonal factors. There is a female predilection and increased incidence during the first trimester of pregnancy.

• Hemangiopericytomas are vascular tumors derived from pericyte cells (Zimmerman pericytes) that surround capillaries and postcapillary venules, accounting for approximately 1% of all vascular tumors. Hemangiopericytomas are usually well-differentiated tumors with a low potential for recurrence with complete resection. The treatment of choice is surgical resection.

• Salivary gland tumors arising from minor salivary glands in the sinuses are rare. The most common is pleomorphic adenoma.

• Chordomas are benign, locally aggressive tumors arising from notochord. They are usually found in the clivus and often present with cranial nerve palsy.