Is having alzheimer's similar to living with cancer?

Yes, somewhat.: These can be similar because both can be progressive, and both can result in permanent deficits. Alzheimer's starts slowly, but as it continues, family members notice clear deficits in daily organization of things like finances, etc., to the point where they cannot recognize family members. Certain cancers, like pancreatic cancer, can start with jaundice and progress to pain and weight loss.

No: Alzheimer's disease is a progressive loss of cognitive abilities and function while with most cancers, the person can function well until shortly before death.