T2 T1 post-gad T1 post-gad

Diagnosis: Squamous cell carcinoma arising in an inverting papilloma

Inverting papilloma is a histologically benign, but locally aggressive epithelial neoplasm which usually arises in the lateral nasal wall. They usually extend into the ethmoid air cells and maxillary sinus with less common involvement of the sphenoid and frontal sinuses. The lesion occurs more commonly in men between the ages of 50 and 70. The most common presenting symptoms are nasal obstruction and epistaxis. Inverting papillomas belong to a larger category of papillomas of the sino- nasal tract; including fungiform papilloma and cylindrical cell papilloma. Less than 4% of inverting papillomas are bilateral. An association with inverting papilloma and human papilloma virus has been invoked. Inverting papillomas are not believed to be associated with environmental stimuli such as smoking due to their high probability of unilaterality. Up to 10% of inverting papillomas may lead to squamous cell carcinoma.

On imaging, inverted papillomas typically appear as nasal cavity masses with variable extension into the paranasal sinuses which tend to remodel bone, rather than destroy it. They may spread into the anterior cranial fossa and the orbit. They enhance homogeneously and have variable signal on MR but are usually isointense on T1 and slightly hypointense on T2. Although calcifications have been reported within inverted papillomas, these are actually fragments of bone. As in this case, the calcifications within the lesion, seen on the coronal CT, are actually pieces of the turbinates.

The relatively less invasive nature of this lesion may be suggested by the presence of adjacent remodeled bone. These findings are more commonly associated with entities such as inverting papilloma, lymphoma, plasmacytoma, and esthesioneuroblastoma. Pure squamous cell carcinomas and adenocarcinomas tend to destroy adjacent bone before it is has a chance to be remodeled. At surgery, in addition to the obvious tumor in the nasal cavity and ethmoid air cells, tumor was found in the intracranial fossa, the left orbit, and the sphenoid sinus. The maxillary sinus was uninvolved. Related Cases

McCary WS, Gross CW, Reibel JF, et al. Preliminary report: endoscopic versus external surgery in the management of inverting papilloma. Laryngoscope, Apr 1994; 104(4): p415-9.

Yousem DM, Fellows DW, Kennedy DW, et al. Inverted papilloma: evaluation with MR imaging. Radiology, Nov 1992; 185(2):p501-5.

Woodruff WW, Vrabec DP. Inverted papilloma of the nasal vault and paranasal sinuses: spectrum of CT findings. AJR, Feb 1994; 162(2):p419-23.

Bawa R, Allen GC, Ramadan HH. Cylindrical cell papilloma of the nasal septum. Ear, Nose, & Throat Journal, Mar 1995; 74(3):p179-81.

Angiofibroma SCCA Esthesioneuroblastoma