We aren’t flat… right?
We aren’t flat… right? This is not a trick question. As much fun as we might have being Flat Stanley and traveling the world in an envelope, people are decidedly not flat – we are three-dimensional creatures. But when doctors are trying to figure out how to best treat a patient’s cancer, they rely on technologies that treat patients like flat people. Determining what type of cancer someone has, and how to treat it, is largely done the same way it was a century ago – using microscopes to look at 2D slides.
Just like a few photos of a house wouldn’t be enough to decide whether you want to buy it, looking at a few 2D slides of a patient’s cancer can miss important information doctors need when choosing the best course of treatment. In a field where mistakes can be deadly, incomplete information is a major problem. Researchers at the University of Washington think they can fix this issue. They’re developing a microscope that takes 3D images instead of 2D pictures, which they hope will allow doctors to make better treatment decisions.
One of the first steps in treating many cancers is taking a biopsy, a small piece of tissue that is cut from a tumor. Doctors look at this piece under a microscope to figure out what kind of cancer someone has, and how to treat it.
Making an accurate treatment decision is critical. Take prostate cancer for example, which affects one in eight men in their lifetime but is frequently not aggressive. Treatment with surgery can have serious side effects, like incontinence or impotence, so the best approach for those with nonaggressive tumors is often to monitor the disease rather than treating it immediately. However, some forms of prostate cancer are very aggressive, and leaving them untreated would mean a high risk of death.
The appearance of the biopsy tells doctors which of these two types they’re dealing with and whether or not treatment is needed. If doctors get this wrong, that could mean doing unnecessary surgery with major side effects. Or worse, it could mean delaying treatment of an aggressive cancer that spreads and causes further complications.
Currently, doctors look at the biopsy by cutting it into hundreds of 2D slices, and then putting just a few of those slices on glass slides and looking at them under a microscope. In the case of prostate cancer, they are looking for abnormally shaped glands (small tubes in the prostate) that indicate how aggressive the disease is. This process is where errors can arise, in part because doctors can miss important features based on which slices they choose. It’s like trying to decide if a loaf of bread is moldy by only looking at two slices. If those slices look good then maybe the whole loaf is fine – then again, maybe not.
The microscope being developed at UW instead uses “sheets” of light to take pictures of thousands of different planes in every biopsy. The microscope puts all these pictures together into a 3D image of the entire biopsy. Doctors can then look around this 3D image (think Google Earth) and get a more complete picture of the cancer than they could with just a few 2D slides. This strategy can reveal critical features that would otherwise be missed.
The 3D microscope is still being tested, but if the promising results seen so far hold, it would be a powerful new tool in the battle against cancer. Doctors would literally see cancer in another dimension, and patients would know their cancer is being treated in the best way possible.
Kevin Bishop builds machines that shoot lasers at brains to make them glow–a key part of 3D microscopes that scientists and doctors can use to look at individual brain cells. His goal is to use light to make tools to treat brain diseases like cancer and Alzheimer’s.