Brain operations are always a last resort, of course, but my wife had to have two. The tumour was bound-up in facial nerves. To protect it, doctors have since sewn the lids together. At the time I researched meningiomas. They happen to only one in 22,000 people each year.
Most sufferers are elderly, most such tumours are in reasonably accessible parts of the skull.
My testimony is that my faith is somehow stronger because of the suffering I have experienced. I can't really tell you why. The final thing to say in this debate is that God does understand. This is not a glib statement, but a truth borne out in scripture and in my experience. Some years ago, while at a large Christian conference, I saw a tiny baby sleeping in a pushchair.