Alumna Dr. Stewart speaks about her research on early detection for lung cancer
On Wednesday 23, Mount Allison Alumna Dr. Erin Stewart was part of the speaker series hosted by the Chemistry and Biochemistry Society. Through a meeting on Microsoft Teams, Dr. Stewart discussed her experience in lung cancer research, as well as the journey from her undergraduate degree to her post-doctorate degree. Stewart graduated from Mount Allison in 2012, and currently works as a clinical research manager at Pentavere in Toronto, a healthcare technology company.
Stewart began her research journey in chemistry but has dabbled in several different fields of research over her career. “You know, we can start in chemistry [or] biochemistry, but you can really go in a lot of different directions; you’re not necessarily restricted to one path,” said Stewart.
No matter what field of research she went into, Stewart explained she only had one goal: improving the outcomes of lung cancer patients. Stewart explained that her goals for lung cancer research were inspired by her grandfather’s passing from lung cancer, and the fact that lung cancer is the leading cause of cancer-related deaths world-wide. “Most of us, when we think of lung cancer, we think of people who have been heavy smokers throughout their lifetime; but actually, we’re seeing a significant increase in people who have never smoked who are getting lung cancer. Part of the reason lung cancer [is] so deadly and it is quite prevalent, [is] we don’t tend to detect it until it is in a very late stage and it has already spread throughout the body. Which makes it quite difficult to treat,” said Stewart.
Stewart got her PhD in the Department of Medical Biophysics at the University of Toronto. Stewart focused on figuring out how to choose the right type of treatment for each patient as well as why patients eventually develop a resistance to them. She focused on EGFR (epidermal growth factor receptor) target therapies (when EGFR is activated the cell will grow). Stewart said, “In about 10-70% of lung cancers —depending on what population you’re looking at— this EGFR might be altered so that it’s constantly stuck in its active state, and that is what is driving the cancer.”
She continued, stating that, “If you can understand what’s causing the cancer and develop a drug against it, when you give it to patients it tends to work quite well. Unfortunately, most of the time, even though it works well initially, patients will develop resistance to the treatment and the cancer will come back.” In one experiment, in order to figure out why patients built up resistance to drugs, Stewart took parts of tumors from patients and put them in immune-compromised mice. She then conducted clinical drug trials in order to evaluate how the tumors built up a tolerance to the drugs given. Even though it seemed as if the cancer was gone when the mice were dissected, there were still traces of the tumor in their systems.
Stewart also spoke about her time at the Princess Margaret Cancer Research Center where she managed an early detection of lung cancer research program. The program was designed to figure out if there were ways to optimize the current screening methods and if there were ways to use these screening results to improve the overall diagnosis process. She explained that there are not many standard practices used to improve screening for patients; however, there are many experimental studies being done in order to improve screening. Most of these experimental studies are looking at the use of chest X-rays and low dose CT scans as a potential way of using screening methods to improve the diagnosis process. Some of the studies were found to be highly successful but had a significant false positive rate. “So, there’s still a lot of work that needs to be done in order to improve this methodology if we really want to make it an efficient use in the real world,” Stewart explained.
That is where the program that Stewart worked on came in. Headed by Dr. Geoffrey Liu, Stewart took part in a program called Lung CALIBER (Clinical and Liquid Biopsy, Informatics, Breathomics, Radiomics) to screen for the early detection of lung cancer. The program tried four different techniques to screen for lung cancer. They explored each technique separately as well as in combination with each other for screening. For radiomics (a field of science that uses AI to improve and automate image analysis), one can feed an image into AI that radiologists suspect of cancer and pull out the information surrounding the image (like shape or texture of the mass/tumor). It can combine some of the radiomic and clinical features about the patient to predict whether an individual has lung cancer. For liquid biopsies, blood is drawn from the patient to detect cancer-derived molecules circulating in the blood. Drawing blood and testing for presence of cancer-derived molecules in the blood allows for the detection of cancer early on. The blood testing is not limited to lung cancer screening. Breathomics is when one breathes into a device called a cyranose to detect cancer in the breath. Although this technology is in its very early stages, it has promising results for detecting lung cancer.
Stewart also mentioned the research she is currently working on. She is examining the current treatment practices used in the field for patients. She explained that not all doctors use the same treatments, and that information was mainly accessible through medical records —which until a couple decades ago were not digitized. The goal is to digitize all patient medical files to make them more accessible and in a more structured format. “So really, there has been a huge blockage in people being to access this information,” Stewart said. According to Stewart, this is a huge problem. About 80% of health records are not electronically accessible. Pentavere uses algorithms to extract information from patients’ health records and put them in an electronic and readable form, in a timely manner.
Following the presentation there was an informal Q&A about Stewart’s journey from undergraduate to graduate school and helpful advice for students’ considering pursuing the same path. “We were very lucky to have Dr. Stewart come present to us. As a recent Mt. A grad and researcher in her field, she was a great person to ask advice about post grad opportunities and show us about unique opportunities that can arise from post-grad research,” said Maggie Pickard, VP of Biochemistry for the Chemistry & Biochemistry society. Dr. Stewart’s research was enlightening and displayed that research can take students in many directions. She showed that there are numerous possibilities for students out there, as long as they have an open mind to them all.