11.   A tumor can grow for a long time before it causes discomfort or pain.

12.   But cancer cells can build tolerance to Tamoxifen, allowing new tumors to grow that are resistant to it.

13.   But all these tumors eventually grew again.

14.   But his tumor recently grew again and he underwent radiation therapy.

15.   But often, when the drug is stopped, the tumors grow back, because some of the blood supply is able to survive.

16.   But the process is hijacked by malignant tumors, which recruit the tiny new vessels to nourish them so that the tumors can grow and spread.

17.   But when the tumors do grow and metastasize, the body is often attacked with a destructive vengeance.

18.   But when denial extends more than a few months, it rapidly becomes harmful as tumors grow and spread.

19.   Colonic tumors grow slowly and spread slowly.

20.   Do all such tumors eventually grow and spread, or only some?