Greg Armstrong, MD, MSCE

As a physician-scientist in the Department of Epidemiology and Cancer Control, I have responsibilities in both the clinical and research spheres. On the clinical side, I provide care for neuro-oncology patients as well as long-term survivors of childhood brain tumors. My research is a natural extension of my clinical work, where I focus on the long-term health impact of the cancer therapies my patients and other survivors received.

I serve as the principal investigator (PI) of the Childhood Cancer Survivorship Study (CCSS), a multi-institutional and multidisciplinary collaborative resource for evaluation of the long-term outcomes of children with cancer who survived five or more years after diagnosis. Continuously funded by the National Cancer Institute since 1994, the CCSS is the world’s largest established open resource for survivorship research. The CCSS has more than 38,000 eligible survivors available for investigation of late mortality and more than 25,000 participants who have contributed valuable information on health-related and quality-of-life outcomes. The CCSS includes comprehensive information on treatment exposures, ongoing longitudinal follow-up, and an established biorepository from which genotype (SNP array) and DNA sequencing of survivors are available.

As the CCSS continues to grow and evolve, participating investigators and institutions are expanding the collection of data to evaluate the physiologic and neurocognitive function associated with aging. We are working to characterize accelerated aging in childhood cancer survivors and investigate the underlying pathophysiology of survivors as they enter their fourth, fifth, and sixth decades of life.

Given the unique healthcare needs of survivors, we are conducting health services research through the CCSS to evaluate patient, provider, and health care system factors and their associations with access, quality, and the cost of care. Ultimately, we aim to provide a resource to identify how survivors’ healthcare quality influences outcomes. 

In addition to my role as PI for the CCSS, I serve as the co-program leader for the Cancer Control and Survivorship Program, one of the five major programs within the St. Jude Comprehensive Cancer Center. I also have a robust line of research inquiry that has evolved into an intervention trial for frailty and senescence. Over the last decade, it has become evident that the biological age of childhood cancer survivors may be advancing faster than their chronological age. To better understand the biology behind that advanced physiologic aging, I collaborate with a colleague from the Mayo Clinic on a placebo-controlled intervention that tests the efficacy of senolytic agents. These agents halt a process called cellular senescence—one of the mechanisms responsible for premature aging—and the trial explores whether these drugs help improve frailty and senescence in cancer survivors.

All my work seeks to advance our knowledge of childhood cancer survivorship so we may ultimately improve quality of life and outcomes well past the initial years of survivorship.