Non-Small Cell Lung Cancer: EGFR Mutations and Targeted Therapies
Continuing our series on non-small cell lung cancer, this week Real World Health Care speaks with Lecia V. Sequist, MD, MPH, Associate Professor of Medicine at Harvard Medical School and the Mary B. Soltonstall endowed chair in oncology at Massachusetts General Hospital. Dr. Sequist’s research focuses on studying novel targets and targeted agents for lung cancer treatment, particularly those that target the epidermal growth factor receptor (EGFR) and in detecting and studying the significance of tumor cells circulating in the bloodstream.
Real World Health Care: Tell us about what you do at Massachusetts General Hospital, especially in relation to research and treatment of non-small cell lung cancer.
Lecia Sequist: I’m a medical oncologist with a busy practice, seeing and treating patients with lung cancer. I also conduct clinical and translational research on new drugs, looking at the molecular aspects of tumors and biopsies as patients go through various forms of treatment. My focus is on personalizing treatment for each patient.
RWHC: Can you share some highlights of your recent research in non-small cell lung cancer?
LS: Most of my recent research has revolved around EGFR mutations. One of the biggest advances in lung cancer in recent years is that we’ve come to understand lung cancer is not one disease. It’s many diseases. We can now tell the difference between one cancer and another by looking at the tumor genetics. These are not the genes we inherit from our parents, rather they are genes that reside only in cancer cells. These genes are at the core of what causes cancer. By identifying these genes in a lung cancer patient’s tumor, we can be more successful with treatments that target those genes and the proteins they produce.
EGFR mutations were first discovered here at Mass General, right around the time I started in oncology. It was a very exciting time, and ushered in a new era of personalized treatment for cancer. Since those early days, we’ve done a tremendous amount of research with patients who have the EGFR mutation, and we’ve found treatments that work better than standard chemotherapy.
RWHC: What are some of the biggest challenges you face as a researcher studying non-small cell lung cancer?
LS: I think of the challenges in two categories: scientific and societal. From the scientific point of view, we can’t currently identify mutations in every lung cancer, though we’re constantly working to uncover more of them. The group of lung cancer patients who have no identifiable mutation, or who have a mutation with no matching drug therapies at this time, are effectively left out of the “molecular revolution.” For those groups, the challenge is to find alternative approaches. Luckily some of the newer immunotherapies may work particularly well in such patients. Then down the road, we know that targeted therapies eventually “wear off,” in the sense that cancer cells get smart and find ways to work around the roadblocks we put in their path. For example, we saw this with the first generation of tyrosine kinase inhibitors (TKIs) developed to target EGFR mutations. Most patients initially responded, but subsequently developed a resistance after about a year, because they developed a second mutation that prevents the TKIs from binding to the cancer cells. Last year, a new EGFR drug was FDA approved that is able to effectively target this second mutation. Now we’re racing trying to learn how the cancers may get around the newer drug and also looking at strategies to prevent resistance.
From a societal standpoint, one of our biggest challenges in the lung cancer research community is the stigma that still exists around lung cancer. In the United States, we were fortunate to have had a very successful public health campaign around the dangers of smoking over the last generation. Those dangers are important to understand, but one of the unexpected consequences of this was to popularize the opinion that lung cancer is a self-inflicted disease and therefore patients carry some degree of blame. Not only does this end up negatively affecting individual patients, it also cuts into research funding. The fact is, some smokers get lung cancer while others don’t. And more importantly, many lung cancer patients have never smoked. No one deserves lung cancer and research must push forward to stop this, the deadliest of all cancers.
RWHC: What are some of the biggest challenges you face as a clinician treating patients with non-small cell lung cancer?
LS: There are promising treatments being studied in clinical trials, but many patients don’t have access to those treatments because the trials are concentrated in academic centers. Even if patients have geographic access to research studies, clinical trials have fairly high thresholds for eligibility, so if a patient has other medical conditions — which many lung cancer patients have — or if their cancer has certain characteristics, they won’t be eligible for the trial. We need to keep pressure on the pharmaceutical industry to include broader groups of patients in trials so all patients can get access to promising new treatments.
RWHC: What do you think are some of the biggest opportunities for advancement in how we research non-small cell lung cancer and treat people with the disease?
LS: Immunotherapy has really changed the paradigm for non-small cell lung cancer. Years of failed vaccine studies led us to believe that it wasn’t possible to affect the human immune system in meaningful ways against lung cancer. Now that we’ve hit upon a different way to activate the immune system, new discoveries are tumbling out the door every day. Unlike past treatments, immunotherapy has true promise for long-term disease control. There are already three FDA-approved lung cancer immune therapy treatments over the last year and likely many more to come. I think someday we’ll look back on this time and say that this is when the needle really started to move.
RWHC: Why did you get into this field of research? What continues to inspire you?
LS: I was initially drawn to studying lung cancer when I was in training by the doctors who were mentoring me and the patients I met. At the time, there weren’t many treatments available for non-small cell lung cancer, so there was a lot of room for improvement. This was attractive to me as a clinician and a researcher and it has remained a vibrant and ever-changing field. I enjoy being involved in the exponentially increasing number of treatments available and how these new treatments can bring hope to patients. It has ended up being an intellectually stimulating and extremely fulfilling career and I continue to be inspired by the patients I meet every day.