Tumor with perineural invasion

.SRB&;S Manual of Surgery 4th edition pg Adenoid cystic carcinoma has got high affinity for perineural spread both axially and circumferentially, antegrade and retrograde fashion along mandibular and maxillary divisions of trigeminal nerve and facial nerve. It infiltrates nerve more proximally for long distance. Tumor may reach Gasserion ganglion, pterygopalatine ganglion and cavernous sinus.