What do the terms in my mom's pathology letter mean?

Nicky1234 Asks:My mom is recently diagnosed with ovarian cancer. The pathology letter mentioned: -Bilateral ovarian adenocarcinoma -Papillary serous systic type -moderately differentiated -vascular invasion: identifed -perineural invasion: dentified -endometrium: inactive -tubes: tumor free -staging: T1C (tumor is seen in both ovaries with involvement of ovarian surface and omental seeding).If