Treatment of cancer has shifted from treating tumors by tissue origin to selecting targeted therapies. Cancer treatment is based on genetic and molecular profiles of cancer. Next Generation Sequencing, NGS, and Whole Exome Sequencing, WES, re-define classification and methods of cancer treatment. Leading precision medicine expert and pediatric hematologist-oncologist shares a vivid clinical case. A couple of months ago in the department we had a child with cancer. I show you photos of child with cancer with permission of the parents. Dr. Shai Izraeli, MD. We had a child with this tumor. Dr. Anton Titov, MD. The child was four months old. Terrible! You want me to put it on the screen? This child had this tumor. His cancer progressed on chemotherapy. We thought he will die. Then we did genomic sequencing of his tumor. We found this genetic abnormality. Because I'm a leukemia expert, I knew about a very rare case of leukemia with this same genetic mutation abnormality. At that time this genetic mutation was put into mice. The mice were cured by a new inhibitor cancer medication. I googled the medication. Dr. Shai Izraeli, MD. I found that there was a clinical trial with this new cancer inhibitor. We gave the child in a clinical trial this inhibitor. This is a picture of tumor before cancer treatment. This picture of cancer is two weeks after starting targeted tumor therapy. Now this is two months later. Gross tumor disappeared completely! Unbelievable! Yes! Dr. Anton Titov, MD. Now, what is the relevance of this child cancer case example to leukemia? Because this is a typical new cancer treatment method at the age of precision medicine. The cancer treatment is against the genetic abnormality. Treatment of tumor is not against the disease as it is defined by affected organ. This genetic abnormality is called TRK. This is an excerpt from a paper that I wrote. It is published in Blood, a journal of hematology oncology. This genetic mutation is found in many subtypes of cancer. It exists in brain cancer, blood cancer. Dr. Shai Izraeli, MD. This child’s cancer was a chest wall cancer. But it is a very rare cancer. What is the implication? The implication is that you have to test genomics, you must sequence DNA in all cancer cases. Because if you find this genetic abnormality, then you can treat it with new inhibitor. It is a targeted chemotherapy. But there is no benefit to use other cancer medications for patients that don't have this genetic abnormality in their cancer. Dr. Anton Titov, MD. In other words, when we deal with precision medicine, we don't anymore deal with only a specific disease. Dr. Shai Izraeli, MD. We do not deal with only a leukemia or brain cancer. This type of cancer is a soft tissue cancer. But cancers from different organs are caused by the same cause. Then tumors may be treated as the same disease. I have several such examples. This is not the only one example of child cancer. This is really the age of precision medicine. That's the meaning of the precision medicine. It happens in many areas of oncology. You move from classification of cancer by the organ or by the tissue. You move to the classification of cancerous tumors based on genetic and molecular signature. Dr. Shai Izraeli, MD. We can use this example. This is a solid tumor, it's not a leukemia. But it's very relevant to leukemias. Because only 1% of leukemias have this molecular abnormality, TRK mutation. But 30% of brain tumors below the age of three have this molecular abnormality, TRK.