A CT Chest With Contrast Was Performed. Impression: 1.) Abnormal

A CT Chest with contrast was performed. Impression: 1.) Abnormal chest x-ray appearance is caused by enlargement of the ascending thoracic aorta which measures up to 4.1 x 4.4 cm. This could be secondary to bicuspid valve. 2.) Soft tissue mass in the upper abdomen, interposed to the duodenum and the cava, causing some mass effect on the cava. This is of uncertain etiology or significance. Some of the main considerations would include gastrointestinal duplication cyst, lymphatic malformation, or lymphadenopathy. Less likely diagnostic considerations would include a neural tumor or sarcoma. If the patient has prior studies at an outside hospital, comparison would be helpful to determine chronicity of this lesion. If none are available, reasonable first starting point would be MRI of the abdomen, to determine if this lesion is cystic or solid.
This patient has a strong family history of heart disease and the lipid panel results were as follows... HDL 36, LDL 278, non HDL cholesterol 326.
Which impression above (1 or 2) should be addressed or further inspected first?