1.   After an injection of lung cancer cells, tumors did develop but did not spread to other sites in their usually aggressive way.

2.   But that does not guarantee that tumors will develop.

3.   If a small tumor develops, Rist could undergo the procedure again.

4.   Osteosarcoma, a rare bone cancer afflicting adolescents, was spreading quickly, and tumors had developed in his lungs.

5.   Researchers said the discovery fleshed out an emerging picture of how a tumor develops.

6.   This insight, if confirmed, should provide a better understanding of how tumors develop, as well as new therapies for interfering with the process.

7.   Tumors develop resistance to chemotherapeutic agents because they have the ability to change their genetic information.

8.   Tumors had developed in laboratory mice whose skin had been painted with condensed roofing asphalt fumes, asphalt-based paint and raw asphalt.

9.   In any case, the tumors never did develop resistance to endostatin, they wrote.

10.   Many die before they reach the age when tumors commonly develop.