Angioimmunoblastic Lymphoma

Does anyone out there have or heard of Angioimmunoblastic Lymphoma? My husband was diagnosed in June. He has been getting chemo treatments, his last treatment is on Thurs and then he goes for a PET scan to determine if he should have a bone marrow transplant. I am very scared and nervous for him, I hear this is extremely dangerous, however the outcome could put my husband into full remission.  Any info would be greatly appreciated....