There is said to be hope for a sick man, as long as there is life.

[Ut aegroto dum anima est, spes esse dicitur.]

Marcus Tullius Cicero (106-43 BC) Roman orator, statesman, philosopher

Epistulae ad Atticum [Letters to Atticus], Book 9, Letter 10, sec. 3 (9.10.3) (49 BC) [tr. Shackleton Bailey (1968), # 177]
    (Source)

Cicero says this was his feeling of hope for how things would turn out, as long as Pompey was in Italy -- which he had just evacuated from. Cicero makes it clear this is a common phrase at the time, usually expressed more straightforwardly as "While there is life there is hope" [Dum anima est, spes est.]

(Source (Latin)). Alternate translations:

But as we say of sick people, "while there is life there is hope."
[tr. Jeans (1880), # 63]

As in the case of a sick man one says, "While there is life there is hope."
[tr. Shuckburgh (1900), # 364]

As a sick man is said to have hope, so long as he has breath.
[tr. Winstedt (Loeb) (1913)]