A sinonasal inverted papilloma of mixed histology: implications for management of all sinonasal papillomas

Ear, Nose & Throat Journal, Dec, 2007 by Jacob D. Steiger, Alexander G. Chiu

Abstract

Sinonasal papillomas ape classically categorized by their histology. Inverted, cylindrical, and fungiform are the three subtypes used to describe these lesions, and their medical and surgical management is often based on the specific subtype. We describe a case of a sinonasal papilloma with all three subtypes represented within the same surgical specimen. To our knowledge, this represents the first such case in the literature and has implications for the management of all sinonasal papillomas.

Introduction

The management of sinonasal papillomas has largely been based on biopsy-proven identification of their histologic subtypes. Cylindrical and inverted subtypes are aggressively treated because of a relatively high recurrence rate and potential for malignant transformation. Fungiform papillomas often are locally excised or, sometimes, simply observed because they have not shown the potential for malignant transformation. (1,2)

A possible flaw in this decision tree is encountered when the initial biopsy misguides the management plan. We present a case of a sinonasal papilloma in which all three histologic subtypes were found within the same specimen. The implications of this pathologic finding may change how all sinonasal papillomas, regardless of the initial subtype on biopsy, are managed.

Case report

A 53-year-old man presented with a 3-month history of nasal congestion. A right-sided nasal mass arising from the lateral nasal wall was diagnosed by rigid nasal endoscopy, and a biopsy performed in the office confirmed the presence of a sinonasal papilloma of the inverted subtype. Computed tomography was performed, showing a right middle meatus mass with opacification of the right maxillary sinus and destruction of the right medial maxillary wall. Magnetic resonance imaging (MRI) of the paranasal sinuses showed a mass pedicled on the right posterior maxillary wall with retained secretions filling the right maxillary sinus.

The patient underwent a right endoscopic medial maxillectomy, complete ethmoidectomy, and sphenoidotomy. Intraoperatively, the tumor was confirmed to be pedicled on the posterior wall of the right maxillary sinus. The tumor and the underlying mucosa of the maxillary sinus were removed, and the bony surface of the posterior maxillary sinus at the site of tumor attachment was drilled down with a 70-degree diamond burr. Final pathology revealed a sinonasal papilloma with separate and distinct areas of fungiform, inverted, and cylindrical histologic features (figure, A and B). There was no evidence of dysplasia, and the patient did well postoperatively. He has remained disease-free 24 months following the surgery.

Discussion

To our knowledge, this is the first reported case of a sinonasal papilloma demonstrating multiple histologic subtypes. It illustrates that a small biopsy of a sinonasal papilloma may not be representative of the entire specimen. This is an example of how basing management decisions on a biopsy of a large sinonasal papilloma could prove to be costly.

Inverted and cylindrical papillomas are most commonly found on the lateral nasal wall, whereas fungiform papillomas are most frequently encountered on the nasal septum. Since the inverted and cylindrical subtypes have malignant potential, management has traditionally been surgical and more aggressive. Medial maxillectomies through external incisions, which are now often performed endoscopically, are routinely performed for these lesions. Fungiform papillomas have often been treated by local excision and have at times been simply observed. A lesion that contains distinct areas of the histologic subtypes, as seen in this case, may lead to improper conservative management if the initial biopsy is read as a fungiform papilloma.

Once a nasal mass has been diagnosed as a sinonasal papilloma, it may he wise to treat all lesions, and certainly those that are large and located along the lateral nasal wall, as if there is potential for the presence of inverted or cylindrical subtypes. It is also important to take into consideration the rest of the clinical picture when making treatment decisions. Large size, evidence of bony erosion, and a characteristic stranding pattern on MRI are further clues that these lesions should be treated as if they hold the potential for malignancy and/or a high rate of recurrence. This would lead to a more thorough excision and closer follow-up.

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Conclusion

Our discovery that a sinonasal papilloma may contain fungiform, cylindrical, and inverted histologic subtypes within the same specimen holds implications for the management of all sinonasal papillomas, and should serve as a precaution to those physicians who manage papillomas conservatively based on an initial biopsy showing the fungiform subtype.

References

(1.) Christensen WN, Smith RL. Schneiderian papillomas: A clinicopathologic study of 67 cases. Hum Pathol 1986;17(4):393-400.

(2.) Hyams VJ. Papillomas of the nasal cavity and paranasal sinuses. A clinicopathological study of 315 cases. Ann Otol Rhinol Laryngol 1971;80(2):192-206.