From what I can tell, this sort of falls into the 1st category, along with a bit of the 3rd. They take the patient's cells and look for a type of rare white blood cell called [tumor-infiltrating lymphocytes]( https://en.wikipedia.org/wiki/Tumor-infiltrating_lymphocytes) that can hit the cancer cells specifically, then make a bunch more of them and put them back into the patient. It's promising because the treatment is effectively an extension of the patient's own immune system (it won't provoke an immune response or poison the person's own cells), the TILs can reach anywhere that the bloodstream can reach (helping to deal with metastasis), and because there is potential for this type of therapy to work on multiple different types of cancers (rather than a specific drug targeting a specific cancer's oncogene).
I just finished The Emperor of All Maladies and it's a terrific read. The timing of this research result is pretty neat.