In the next few years, the biggest advancements in cancer care may occur at the smallest level, the level of individual molecules.
By imaging individual molecules on cancer cells, malignancies can be detected when they are smaller and more easily treated. Targeting individual molecules has also allowed groundbreaking new therapies with great precision, increasing the efficacy of treatment and minimizing side effects.
This effort sounds like something out of “science fiction,” but the field of molecular imaging and therapy (MIT) is already “science fact” and impacts the care of patients with many types of cancer, such as prostate cancer, breast cancer, myeloma, and neuroendocrine tumors.
What is molecular imaging and therapy (MIT)?
To understand this field of medicine, it helps to imagine a lock and a key. Every tumor has molecules on it and inside it. These are the locks. We can design agents that specifically bind to these tumor molecules, acting like keys fitting into the locks. We can then add things to our keys that allow us to image or treat a tumor. If we add an isotope that emits a small amount of radiation that can be detected and localized in a positron emission tomography-computerized tomography (PET/CT) scanner, our key will fit into the lock and let us know where the cancer is. If the add an isotope that emits a large amount of radiation, enough to kill cells, now our key will fit into the lock and deliver cancer-killing treatment directly into the cancer cell. MIT images and treats cancer at a molecular level.
Every treatment has side effects, and these are no exception, but because we can bring the therapy to the cancer cell through this “lock and key” approach, in general, we see fewer side effects and more precise, targeted therapy.
Currently, the field is exploding with the search for keys that help us locate and treat cancer. As we discover the right “keys, ” we’re able to use advanced imaging to locate cancer cells throughout the body.
For example, in breast cancer, the molecule fluoroestradiol attaches itself to estrogen receptors that are present in 80% of breast cancer tumors. This key can “light up” tumors on a PET/CT scan, allowing us to detect the spread of cancer more sensitively than ever before. Keys like this exist for prostate cancer, neuroendocrine tumors, myeloma, and other cancers.
What the future holds
For many years to come, the most effective treatment of localized solid tumors will remain surgery. So long as the cancer hasn’t spread, surgical removal of a tumor is the best chance for a cure. But for cancers that have spread, Molecular Imaging and Therapy holds tremendous promise in the near future. There is already FDA approval of MIT agents for neuroendocrine tumors and breast cancer. I expect we’ll see FDA approval for imaging and treating prostate cancer within one to two years.
Ultimately, the goal of this field is to detect a single cancer cell, eradicate it and ensure that a patient never develops a tumor. This will take some time to achieve. And, in another decade, I expect this field will advance beyond cancer and into cardiac treatment, neurology and infectious disease.
When we’re focused on something as small as a molecule, there’s nothing stopping the medical profession from thinking big.
Gary Ulaner is a radiologist, Hoag Memorial Hospital Presbyterian, Newport Beach, CA.
Image credit: Shutterstock.com
