Reoccurrence is not the same as a first occurrence. Most tumors contain a small percentage, approximately 2%, of MDR (multiple drug-resistant) cells. Chemo is not effective against these cells. After the first round of chemo, if the chemo is effective, all of the cells that are not MDR, are destroyed. Since this accounts for the vast majority of the tumor mass, the tumor appears to be effectively destroyed. However, the MDR cells remain and start to multiply. If the cancer reoccurs due to MDR cells, the new tumor is likely to be entirely MDR. The next time chemo is used, none of the cells will be destroyed because they are all MDR. This is why giving chemo after a cancer reoccurs often fails to have any effect. A wise patient would ask their doctor to determine what percentage of the new tumors are MDR cells. If you’re tumors turned out to be primarily MDR cells and your doctor, as you say, has recommended chemo again, you has every right to kick him as hard as you can. There is only one treatment that has been shown effective against MDR cells, Paw Paw.