A 38-year-old woman from Delhi presents with a 6-month history of a painless, slow-growing mass in the left parotid region. On examination, the mass is soft, mobile, and non-tender, located anterior to the angle of the mandible. Facial nerve function is intact. Ultrasound shows a well-defined, hypoechoic lesion measuring 2.5 cm with no cervical lymphadenopathy. The patient is anxious about surgery and asks if the mass can be managed conservatively. What is the most appropriate next step in management?