Scarring can definitely occur following a cyst removal, and I am sorry your dermatologist said that this would not happen, as it is a common occurrence following this type of procedure. We recommend patients use Biocorneum, a silicone based scar gel plus SPF, for existing scars. It is also very important that you keep it protected from sun exposure. You can also explore laser options. Patients may opt to do laser genesis treatments, which are non-invasive (no downtime) and aim to help reorganize collagen in the scar, or fractionated CO2 treatments which will help resurface the scar and build collagen. You could potentially explore the option of a scar revision surgery, though this may not be needed. I would suggest you contact a board certified plastic surgeon whose office has laser options for scarring, and schedule a consultation.
Best of luck!