My husband been treated for lymphoma leukomia several years

Patient: My husband been treated for lymphoma leukomia several years ago. It’s in remission. The last 2 daysHe has had no appetite.Difficulty walking,severe pain in his legs and feet. Swelling in his handsIs this a possible sign of his cancer coming back and what should I do

Symptoms: Psin in legs swelling in legs and fingers difficulty walking. He is a diabetic. Had shingles x2. Nerve damage.
Sugars are good. Low readings 90 today.

Doctor: