Anatomic location is a risk factor for atypical and XXXX .

@entity5 @entity1 @entity1653 @entity1313
BACKGROUND: Grade II and III @entity1653 have higher rates of @entity5 recurrence than grade I @entity1653 after surgery and/or external irradiation. As the utility of noninvasive treatments for @entity1313 increases, it is becoming increasingly important to assess the likelihood that a @entity5 is not benign before treatment initiation. Hence, the authors have reviewed a large series of their @entity1 to determine risk factors for higher-grade pathology, with particular interest paid to @entity5 location. METHODS: The authors reviewed 378 @entity1 presenting at their institution from 2000 to 2007 with histologically confirmed @entity1653 , central pathology grading according to the World Health Organization 2000 guidelines, and @entity5 location confirmed with preoperative imaging. They performed univariate and multivariate logistic regression on potential risk factors for high-grade pathology. RESULTS: Risk factors for grade II/III pathology included nonskull base location (2-fold) and male sex (2-fold). @entity1 with prior surgery had a 3-fold increased incidence of higher-grade @entity1653 at presentation at the authors' center. The authors controlled for this referral bias by performing a multivariate regression, and analysis without @entity1 receiving prior treatment. Ninety-seven percent of operations were performed for @entity5 size and clinical symptoms, whereas <3% were performed for interval growth or features concerning higher-grade pathology. CONCLUSIONS: Nonskull-base @entity1653 , male sex, and prior surgery impart increased risk for grade II or III pathology. This increased risk translates to probable poorer prognosis and increased likelihood of recurrence after treatment. Thus, it is prudent to take these specific variables into consideration in conjunction with the complete clinical presentation when advising @entity1 regarding their prognosis.
