Fig. 1From: Impact of primary tumor volume and location on the prognosis of patients with locally recurrent nasopharyngeal carcinomaMagnetic resonance imaging findings of the common tumor invasion sites in patients with nasopharyngeal carcinoma (NPC). a, the skull base, the most common tumor invasion site (70.4 %); b, the parapharyngeal space (49.8 %); c, the intracranial cavity (32.3 %). The numbers in the pictures represent the order of incidence of tumor invasionBack to article page