This sounds like an adrenal incidentaloma, that is, a tumour of the adrenal gland that was found incidentally. Surgery is recommended if:
A. The tumour is functioning - you will need to see an Endocrinologist to carry out the appropriate tests
B. The tumour is greater than 4 cms in size, which it is not
Otherwise, a follow-up scan is recommended in 3-6 months time to confirm that the lesion is not growing in size.