Professor Stanley Riddell, from the Fred Hutchinson Cancer Research Center in Seattle, U.S. has reported on a set of remarkable results stemming from a new treatment for cancer. This relates to a study where 90 percent of patients (35 in total), suffering from an aggressive type of leukemia (acute lymphoblastic leukemia), made a recovery with no further trace of the cancer. The patients were at a critical stage and given no more than five months to live. Similar successes have been obtained in relation to other types of blood cancers.
Being symptom-free and having no detectable sign of cancerous cells is not the same as being “cured.” The patients are considered to be in remission.
The technique involves taking T-cells (a type of immune cell) from the patients. These cells are then tagged with targeting molecules (called chimeric antigen receptors), designed to target cancerous cells. These modified immune cells are infused back into the patient’s body. The antigen receptors were created in genetically engineered mice.
Many forms of cancer remain aggressive in the body because cancer cells are shielded from the human body’s immune system by the immune cells not recognizing the cancer cells. When the modified T-cells are infused back into the body, they latch onto cancer cells and then signal to the body’s immune system to attack and kill the cancer cells.
Speaking with Sky News, Professor Riddell said: “This is extraordinary. This is unprecedented in medicine to be honest, to get response rates in this range in these very advanced patients.”
In an interview with the BBC, the medic added: “Essentially what this process does is, it genetically reprograms the T-cell to seek out and recognise and destroy the patient’s tumour cells.”
The results have been presented to the American Association for the Advancement of Science (AAAS) annual meeting in Washington DC. The results present the first step. It is not known how long the treated patients will remain cancer free. Moreover, the results to date are only effective against blood cancer — there is no indication as yet that solid tumors can be treated (a fact missed in many other media reports).
With the blood cancer itself, only a small number of patients have been treated, each at an advanced stage. It is unknown if the same effect will be seen with a wider patient population. Nonetheless, the results presented to date are of great interest.
