Skull Base Inverted Papilloma: A Comprehensive Review

Table 6

Cannady’s et al. staging system about prognosis (as operationally defined by RR) for IP managed by advanced endoscopic techniques.

Group	Location and spread	Recurrence rate
Group A	IP confined to the nasal cavity, ethmoid sinus,; and medial maxillary sinus	3.0%
Group B	IP with lateral maxillary sinus, sphenoid sinus,; or frontal sinus involvement	19.8%
Group C	IP with extrasinus extension	35.3%