What is the most characteristic symptom in a lady diagnosed with Pheochromocytoma?

Pheochromocytomas and paragangliomas are catecholamine-producing tumors derived from the sympathetic or parasympathetic nervous system. These tumors may arise sporadically or be inherited as features of multiple endocrine neoplasia type 2. The "rule of tens" for pheochromocytomas states that about 10% are bilateral, 10% are extraadrenal, and 10% are malignant. However, these percentages are higher in the inherited syndromes. The clinical presentation is so variable that Pheochromocytoma has been termed "the great masquerader". The dominant sign is hypeension. Classically, patients have episodic hypeension, but sustained hypeension is also frequent.