It means a 5 mm lesion (shadow) seen on the
CT scan in right lung in its upper lobe (Right lung has three lobes: upper, middle and lower). Since the nodule size is very small 5mm (half of a centimeter), the
radiologist has not been able to give an exact disgnosis and he has given a differential diagnosis (meaning it can be one of the following) of the following:
1. Inflammatory/granulomatous lesion: secondary to infection or foreign body etc
2. Pulmonary metastasis: metastatic disease to lungs is a possibility since you have a primary ovarian cancer
3. Early primary neoplasm: A primary
lung cancer in its very early stages because of the small size.
Since the size of the lesion is very small, a
biopsy would not be possible to confirm the diagnosis. I would suggest a repeat CT scan after 2 months to see if the nodule size has increased. If the size remains stable, its likely to be benign. If it increases to > 1 cm, a PET scan or a biopsy can be done.
I hope I have answered your query. I would be more than happy to answer if you have any further queries.