It is not uncommon for them to remove a fallopian tube if they had to remove the ovary. In your case, it is possible that the cyst was wrapped around the fallopian tube. You would get the best answer if you called the doctor who did the surgery and asked him. You have every right to know what is going on and why the tube was removed. I hope you get the answers you seek soon.
I had a dermoid as well and the doctor removed my ovary and my fallopian tube, This is usually the case when the cyst and ovary are intertwined with each other.
hi i had a dermoid that i was unaware of that twisted and caused my fallopin tube to knot and that knot cut the blood supply off to my ovary ,so my ovary went black and gangerous and died , dont know if that has any connection with you ,i know how you feel its very scary ,i am still trying to get my head around it sorry to read what happened to you keep posted you will get support on this forum x