All are true for plemorphic adenoma except?

Answer is 'd' i.e. None Pleomorphic adenomas arise most commonly in the parotid gland. These form majority (-80-90%) of tumors of the parotid gland. Pleomorphic adenomas are less common in the submandibular glands & sublingual glands; relatively rare in the minor glands. Pleomorphic adenomas are benign tumors derived from a mixture of ductal (epithelial) and myoepithelial cells, and therefore show both epithelial and mesenchymal differentiation (hence k/a mixed tumor) Although benign, it has the potential to turn malignant k/a carcinoma ex pleomorphic adenoma or malignant mixed tumor. The incidence of malignant transformation increases with the duration of the tumor Signs & symptoms suspicious of malignant transformation a) rapid growth b) pain c) paresthesias d) facial weakness e) skin invasion and fixation of mastoid tip.