[Inverted papillomas in the nose and paranasal sinuses]

[A study of surgical procedures for inverted papilloma in the nasal cavity and paranasal sinuses]

Inverted papilloma, although benign, recurs frequently and may become malignant, making definitive initial resection extremely important. We evaluated surgical procedures for recurrence and sites, with special reference to management of the orbital plate of the ethmoid and lacrimal bones, in 24 patients (32 cases) with inverted papilloma of the nasal cavity and paranasal sinuses undergoing surgical resection from 2000. Nine of the 32 showed recurrence, all around the ethmoid orbital plate. Up to 2002, recurrence was noted in 7 of 17 cases (41%), so we changed surgical selection criteria. Since 2003, we have conducted partial and combined excision of the orbital plate of the ethmoid and lacrimal bones (extended operation of the extranasal ethmoid and frontal sinuses) in cases in which tumors adhered to the orbital plate, noting recurrences in only 2 of 15 cases (13%). A number of reports advocate endoscopic sinus surgery to minimize invasiveness for inverted papilloma, but partial and combined excision of the orbital plate is indispensable, in progressive inverted papilloma cases to reduce recurrent.

HPV infections in benign and malignant sinonasal lesions

This review updates the evidence that the human papillomavirus (HPV) is involved in the development of benign and malignant sinonasal lesions. Since the early 1980s, when evidence was provided on the possible involvement of HPV in the aetiology of both benign respiratory papillomas and squamous cell carcinomas, a substantial number of studies have explored this issue. To date, 33.3% of sinonasal papillomas and 21.7% of sinonasal carcinomas analysed have been shown to be positive for HPV. Many elements of the data parallel the observations made in HPV lesions at other mucosal sites, such as malignant transformation and frequent recurrence after radical treatment; the fact that low risk HPV types 6 and 11 are usually confined to benign lesions, whereas the reverse is true for the oncogenic HPV types 16 and 18; and the presence of squamo-columnar junctions and squamous cell metaplasia in the sinonasal system. The discrepancies reported by several studies might result in part from technical reasons, but it is also possible that sinonasal lesions have a heterogeneous aetiology (HPV related and non-related) and/or that some novel (yet unidentified) HPV types exist in these lesions, which are detected by some studies but not by others.

Factors in the pathogenesis of tumors of the sphenoid and maxillary sinuses: a comparative study

OBJECTIVES/HYPOTHESIS

To explain the processes that lead to the development of tumors in the maxillary and sphenoid sinuses.

STUDY DESIGN

A 32-year review of the world's literature on neoplasms of these two sinuses and a randomized case-controlled study comparing the normal mucosal architecture of the maxillary to the sphenoid sinus.

METHODS

Analysis of a 32-year world literature review reporting series of cases of maxillary and sphenoid sinus tumors. Tumors were classified by histological type and separated into subgroups if an individual incidence rate was reported. Histomorphometry of normal maxillary and sphenoid sinus mucosa was performed in 14 randomly selected patients (10 sphenoid and 4 maxillary specimens). Specimens were fixed in 10% formalin, embedded in paraffin, and stained with periodic acid-Schiff (PAS) and hematoxylin. Histomorphometric analysis was performed with a Zeiss Axioscope light microscope (Carl Zeiss Inc., Thornwood, NY) mounted with a Hamamatsu (Hamamatsu Photonics, Tokyo, Japan) color-chilled 3 charge coupled device digital camera. The images were captured on a 17-inch Sony (Sony Corp., Tokyo, Japan) multiscan monitor and analyzed with a Samba 4000 Image Analysis Program (Samba Corp., Los Angeles, CA). Five random areas were selected from strips of epithelium removed from each sinus, and goblet and basal cell measurements were made at magnifications x 100 and x 400.

RESULTS

The literature review revealed that the number and variety of tumors in the maxillary sinus are much greater than those in the sphenoid. The incidence of metastatic lesions to each sinus is approximately equal. No recognized pattern of spread from any particular organ system could be determined. On histomorphometric study there were no statistically significant differences between the sinuses in the concentration of goblet cells, basal cells, or seromucinous glands.

CONCLUSIONS

Factors involved in the pathogenesis of tumors of the maxillary and sphenoid sinuses include differences in nasal physiology, embryology, morphology, and topography. There are no significant histological differences in the epithelium and submucous glands between the two sinuses to explain the dissimilar formation of neoplasms.