Fighting disease with personalized medicine
February 25, 2016At the heart of the 2016 German Cancer Congress lie "four Ps." That is prevention, precision, participation, and personalization.
The organizers of the Berlin meeting say future cancer medicine should focus on prevention, it should also be precise, and increasingly patients will be expected to participate in their own healing process.
Above all, though, tomorrow's cancer treatments will be more personalized than ever before.
But what exactly is personalized cancer medicine?
Usually, when a cancer is diagnosed, doctors administer common therapies: a combination of operating to remove the tumor and a course of either chemotherapy or radiotherapy.
If that's not enough to get the cancer under control, doctors may now switch to a personalized strategy.
By conducting a molecular analysis of tumor cells, doctors can identify active substances that will work against the specific cancer and use them in a targeted way - personalized for just that one patient. This approach often carries less risk than chemotherapy, and may also be more effective.
The first step to personalized treatment is gaining a better understanding of the molecular mechanisms and metabolic processes that allow cancer cells to multiply and spread.
Understanding the cancer and its genetics
Modern sequencing methods allow doctors to decipher the genome of a patient in just a few days. This gives doctors a whole new insight into genetic defects, or predispositions that may be indicators of a higher cancer risk - for example, for breast or ovarian cancer.
If doctors detect a predisposition, patients can use that knowledge to their advantage to alter their lifestyles or go for more regular check-ups.
Or if a cancer has developed, doctors have a chance of fighting it more efficiently than before, using the patient's personal genetic information.
Finding specific substances
Researchers are now able to identify changes in the genetic information of lung cancer cells, called "driver mutations." These are likely responsible for the malignancy of the cancer cells.
They are also finding more and more substances that can act against these genetic variations.
But as different lung cancers will show different driver mutations, doctors have to first sequence the tumor in question before they can determine which substance will inhibit its development. Once they have found the substance, the therapy usually works well.
However, such inhibitor substances usually only work against a very limited number tumor cells. So far doctors have found substances that work against roughly one-fifth of all lung cancer varieties. The search is far from over.
Supporting immune defenses
A promising form of personalized cancer treatment is fighting tumors by strengthening the body's immune defenses.
Oncologists use genetically custom-made proteins, so called "immune checkpoint inhibitors." These antibodies can strengthen or weaken the immune defense system. Various forms of such substances have proven successful in fighting tumors.
Another form of personalized cancer medicine is the search for biomarkers that are characteristic for specific forms of cancer.
By conducting targeted diagnostics, doctors can find out if a specific substance is likely to work, even before giving it to the patient. One way of doing this is mutation testing. It's a way of finding out whether and how a specific tumor cell multiplies after a substance is applied.
Reinventing medicine
Molecular personalization is changing our whole understanding of medicine as active treatments for patients become part of pharmaceutical research and development.
But that won't ensure the success of personalized medicine.
First, licensing procedures will have to get shorter. When it comes to cancer, which often ends fatally, this is something that can easily be justified from an ethical standpoint.
Then, success will also depend on a good exchange of information between cancer research centers and university hospitals.
France is a leader in this field. It boasts a nationwide grid of 28 centers for molecular diagnostics. The grid ensures tissue samples from cancer patients with specific cancers, including all forms of lung cancer, are analyzed. It is making it easier for experts to recommend custom-made, personalized medicine, rather than relying on "off-the-peg" therapies.