I'm asking why a god would make deformed babies, cancer...?
Why wouldn't He?
You say this as though a) people have no value unless they're perfect and free of all unpleasantness in life, and b) the existence of God must require that life be a never-ending day at the beach.
Let's face it, some deformed people are so badly deformed/retarded... that it seems like a punishment of some sort.
Note the word "seems". Perception is not reality. Just because YOU see something as "bad" or a "punishment" because of your emotions coloring your view, doesn't mean it actually IS. A thunderstorm that is a "bad" thing to me because it prevents me from taking my kid to the park is a "good" thing to a farmer whose crops need the water, and a completely neutral it-just-exists thing to the world in general.
The reality is that the human body is designed to be fallible, to have a shelf life. It is designed to be ultimately disposable. It is also an immensely complex mechanism with a lot of moving parts and systems. With all of that in mind, it isn't at all surprising that sometimes, the things that can go wrong with it do so right from the outset.
Furthermore, temporal pleasure and enjoyment are not even remotely the purpose of this entire endeavor. Humans are also not designed mentally and spiritually to function well without stress and conflict and challenge. Come to that, we're not even designed PHYSICALLY to function well without those things (look at what happens to someone who sits on a comfy couch, happily eating his favorite potato chips, without ever exercising and getting sweaty). As much as we don't enjoy it a certain amount of suffering is built into the formula as a necessity.