More than 100 drugs have been approved to treat cancer, but predicting which ones will help a particular patient is an inexact science. A new implantable device, about the size of a grain of rice, can carry small doses of up to 30 different drugs. After implanting it in a tumor and letting the drugs diffuse into the tissue, researchers can measure how effectively each one kills the patient’s cancer cells. Such a device could eliminate much of the guesswork now involved in choosing cancer treatments.
The device, made from a stiff, crystalline polymer, can be implanted in a patient’s tumor using a biopsy needle. After implantation, drugs seep 200 to 300 microns into the tumor, but do not overlap with each other. Any type of drug can go into the reservoir, and the researchers can formulate the drugs so that the doses that reach the cancer cells are similar to what they would receive if the drug were given by typical delivery methods such as intravenous injection.
After one day of drug exposure, the implant is removed, along with a small sample of the tumor tissue surrounding it, and the researchers analyze the drug effects. The device could help researchers identify the best chemotherapy agents and combinations for every tumor prior to starting systemic administration of chemotherapy, as opposed to making choices based on population-based statistics.