Had a ct a few months ago for upper abdominal pain and all came back fine except for mild mesenteric lymph nodes. had another ct and they're still there,my doctors says theirs not explanation because ct is clear besides that. could it still be caner?

Normal mesenteric lymph nodes may show up on ct scans. If they are quite prominent then pathological causes like inflammation, malignancy & infection are possible causes. My sense is that the mesenteric lymph nodes seen on your ct scan are normal ones, but I would review the images with the radiologist and ask him/her if he/she thinks they look normal,whether other studies or a followup advisable