My grandmother aged 65 she had mutiple myeloma and leoimoma can it be cured?what is the treatment?

Yes ; no: Multiple myeloma is not curable. Leiomyoma is the medical term for uterine fibroids. Fibroids can be treated successfully.

Which one is worse?: Leiomyoma sounds like a benign tumor, so it should not cause much of a problem. Multiple myeloma is a cancer inside the bone(bone marrow). There is good treatment for myeloma but it is chronic, long term treatment off and on, most patients can and often live for 5-10 years with this cancer.