Pharma would cure cancer because then more people would get old. Make more money off elderly and all the drugs doctors prescribe them over the long years.
The problem is that cancer isn't one disease. It's a bunch labeled under one name with different causes. Some cancers like certain types of skin cancer can be cured just by removal of the spot.
My niece was diagnosed with a neuroblastoma at 4. It was caught late but hadn't spread any. They removed it and watched instead of doing chemo or radiation. She's 10 now and her yearly checkups have been clear. She'd had a bad reaction to a vaccine and it saved her life. It stressed her body enough that she was showing odd signs. Doctor at the children's hospital was specialized in childhood cancers and recognized some of the symptoms and had her have an MRI. 3 days later was the surgery. They had to delay her next vaccination routine, but she was back on track after that since the vaccines were even more important to her since getting ill was too risky. There is a good chance she'll have a normal life. Because they didnt have to do treatments, she'll actually be able to have kids one day if she wants.