“…By contrast, none of the above factors has been found to be an independent prognostic factor for OS in multivariate analysis. These findings are in accordance with those reported by others [9,14,15,35]. To different degrees, the parapharyngeal space was the most commonly infiltrated region, which has also been documented in other series, due to the little resistance that opening of the sinus of Morgani offers [4,36].…”