Hello,

Thank you for your query.

Prednisone is not prescribed to get strength, though sometimes it helps to increase appetite. In cancerous patient the role of prednisone is not so clear. It may induce apoptotic cell death. It also decreases peritumour inflammatory edema (swelling around the tumour).
As a result, intervention during operation becomes less difficult.

It is very difficult to say how much time it will take to get adequate fitness. It depends on his nutrition, presence or absence of infection and physical condition.

Continue the medication according to doctor's advice.

I hope I have been some help of your query. Please write if you have any doubt.

Take care

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