RAC Primer, page-355

Yes - Breast, ccRCC and melanoma can on rare occasions have spontaneous remissions. They are not common to the point that when they do they are treated as miracles and get saints canonised.

There has never been a medically documented case of AML spontaneously remising. The reason why is most cases of spontaneous remission are the patients immune system suddenly noticing the cancer and attacking it (basically doing what the immune checkpoint inhibitor drugs do). With AML there is no immune system left (it all gets crowded out by the cancer) so there is nothing left to attack the cancer.