Anaplastic astrocytoma is a rare and highly aggressive form of brain cancer. Most commonly found in adults between the ages 30 and 50, it is characterized by aggressive tumor growth in the surrounding brain tissue.
Treatment is quite challenging and only 27% of patients live for five years or more after diagnosis. Dr. Courtney Burnett was diagnosed with anaplastic astrocytoma in January 2020, when she was in her final year of residency in Internal Medicine at the University of Minnesota.
At age 29, she became one of the roughly 15,000 people who are diagnosed with this type of cancer in the US each year. It took multiple challenging surgeries, six weeks of radiation therapy, and six months of chemo to treat and stabilize the cancer.
“After my diagnosis of a rare form of brain cancer, anaplastic astrocytoma, at age 29, I received treatment targeting an IDH mutation. This has become so successful in the brain cancer world, it has revolutionized the standard of care for IDH-mutated brain tumor treatment,” says Dr Burnett.
Thanks to the latest breakthrough in precision oncology, Dr. Burnett was able to beat the cancer, finish her residency, and become an author, motivational speaker, and Hospital Medicine Physician. In this story, we will look at recent advances in precision oncology that are helping young patients like Dr. Burnett successfully survive highly aggressive forms of cancer.
Common Challenges in AYA Cancer Treatment
In the United States, cancer patients between the ages of 15 and 39 years old are typically defined as Adolescent and Young Adult (AYA) patients. They are a relative minority, accounting for just 4.4% of all newly diagnosed cases each year.
While AYAs generally have a good prognosis with a 5-year survival rate of 85.8%, at the lower age ranges, things are not so positive. Dr. Sridhar PS, MBBS, MD, DNB, a senior consultant and expert in radiation oncology, had this to say about adolescent cancers:
“Teen cancers are different from those of children or older adults. They are typically more rare, more aggressive, and more resistant to conventional therapies. Some of the most common types of teen cancers are sarcomas, brain tumors, leukemia, lymphoma, and thyroid cancer.”
Dr. Sridhar highlights the presence of complex genetic mutations as a major impediment to successful treatment. Standard drugs are often unsuccessful in targeting and removing such cancers.
Another major issue is the relatively low incidence of cancers in this demographic. Rarer cancers mean less data on genetics and mutations, and fewer clinical trials aimed at AYA patients. This can drastically limit their access to novel treatments involving immunotherapy and precision oncology.
Regardless, things have improved drastically in the US over the last 50 years. The 5-year survival rate for adolescents aged 15 to 19 has increased from just 58% in the mid-1970s to 86% at present. However, according to the National Cancer Institute, this data is often skewed due to the 99% survival rate seen in thyroid cancer and Hodgkin lymphoma.
In the rarer cancers like stage-3 astrocytoma, the survival rates continue to be low. More than 400,000 AYAs die each year from cancer around the globe, out of which 9200 are reported in the US. Improved access to medical care, clinical trials, and novel therapies can help bring down this number.
The Promise of Precision Oncology in AYA Cancer Care
Precision oncology is a revolutionary new concept in cancer care, driven by recent advances in genetics and molecular biology. It is based on the realization that cancer is a highly complex disease whose genetic and molecular roots can vary widely from patient to patient.
Instead of using a standard treatment like chemotherapy that can hit both cancer cells and healthy cells, doctors can now look for individual gene mutations that are driving a patient’s cancer. Once the gene is identified, they can use a medicine designed to target that mutation and prevent tumor growth.
Next-generation Sequencing (NGS), a technology for the quick sequencing of DNA/RNA, played a crucial role in the rise of precision medicine. “NGS is a quick, cheap way to look at the DNA of a tumor, showing many gene changes. This can highlight the main changes driving the tumor’s growth,” explains Dr. Sumeet Kumar, MD, PhD in Human Genetics.
An expert in the genetic factors driving Parkinson’s Disease, Dr. Kumar is also the founder of Geneswellness.com, an educational blog to demystify the impact of genetics on various aspects of health, including cancer care.
In his opinion, precision medicine is changing the fight against cancer, particularly among AYA patients. Dr. Kumar highlights instances like this 2019 study where NGS led to the discovery of targetable gene changes in 30% of all acute lymphoblastic leukemia cases in children, resulting in improved survival rates.
NGS was also critical in Dr. Burnett’s successful cancer therapy experience. It was used to determine the presence of Isocitrate Dehydrogenase (IDH) mutations, a distinctive feature often seen in brain cancer tumors and acute myeloid leukemia (AML).
Several new therapeutic drugs have received regulatory approval for the treatment of IDH mutations, particularly in the treatment of AML in children and AYA patients – these include ivosidenib and enasidenib. Vorasidenib is currently undergoing clinical trials according to a recent report in the New England Journal of Medicine (NEJM).
Another breakthrough in precision medicine involves Anaplastic Lymphoma Kinase (ALK) – an enzyme and its related gene identified in various cancers like neuroblastoma, anaplastic large cell lymphoma, and inflammatory myofibroblastic tumors. Crizotinib is a novel drug that inhibits ALK and stops its signaling, resulting in the halting of the cancer.
“It has shown remarkable efficacy and safety in patients with ALK-positive tumors, regardless of their age or tumor type. Crizotinib is now approved by the FDA for patients with ALK-positive non-small cell lung cancer and anaplastic large cell lymphoma, and it is being tested in clinical trials for other ALK-positive tumors,” says Dr. Sridhar.
The Future of Precision Medicine in AYA Cancers
Precision medicine has shown remarkable results in treating rare and aggressive pediatric and AYA cancers in recent years. There is no doubt that it has the potential to improve existing treatment modalities to unprecedented levels in the future.
However, Dr. Sridhar also cautions about some sobering realities – precision oncology is a multidisciplinary approach that requires a team of experts including oncologists, pathologists, and geneticists to deliver personalized care to each patient.
“It requires a robust infrastructure of molecular testing, data analysis, drug development, and clinical trials to support its implementation. Moreover, it faces several challenges, such as the cost and accessibility of genomic testing, the availability and affordability of targeted drugs, the ethical and legal issues of data sharing and consent, and the need for more research and evidence on its long-term outcomes.”
Despite these challenges, all the experts remain optimistic about the future of precision medicine in our fight against cancer, particularly among young patients. Dr. Courtney Burnett summarizes it best from her unique position as both a physician and AYA cancer survivor:
“As an AYA cancer survivor and physician, I’m thankful every day for the clinical research that leads to advances in targeted treatment, both for my own health and that of my patients.”
