What they all said!
If asked, you need to answer truthfully, or you could be sacked instantly with no compensation, and total denial of benefits, plus no references. A lie also damages you, as you'll always have that fear of being caught out.
Also, if you have any limitations due to PCa or its treatment (eg frequency, reduced stamina), then you'd be unwise to try and hide them.
Some employers may be sympathetic (so long as you're up to the job), others will discriminate against you. A few will not even consider you (if they have 200 applications, they'll often choose to keep it simple). Most will appreciate the honesty, and that could help. That's the reality.
People do lie to get jobs; they lie about health, experience, qualifications, age. For that matter, employers lie too! But all those who lie are taking a calculated risk. If you're tempted, do a careful risk assessment first ... is it really worth it?