A cancer diagnosis is often unexpected, frightening and life-changing for both patients and family members. But, what if your doctor told you you’re lucky because you have the “good cancer”? Would you feel grateful, and guilty if you didn’t?
This has been a common experience for those diagnosed with thyroid cancer, which has consistently good survival outcomes. For example, the 5-year survival rate for invasive thyroid cancer is 97.9 percent, according to SEER research data from the National Cancer Institute, with more than 95 percent surviving 10 years.
But, a recent paper by University of Chicago Medicine Comprehensive Cancer Center researchers Briseis Aschebrook-Kilfoy, PhD, research associate (assistant professor) of public health sciences, and Raymon Grogan, MD, assistant professor of surgery, shows that thyroid cancer diagnosis and treatment can result in decreased quality of life, and better tools are needed to help patients navigate survivorship.
“The idea behind that ‘good cancer’ statement is a positive one,” said Grogan, who co-leads The North American Thyroid Cancer Survivorship Study (NATCSS) with Aschebrook-Kilfoy. “It is physicians trying to make people feel better. But, I think it’s had the opposite effect over time.”
Incidence of thyroid cancer has increased dramatically in the past several decades. In fact, in a 2011 study, Aschebrook-Kilfoy and Grogan found that thyroid cancer, which is most common in women, will double in incidence by 2019. With high survival rates and a young average age at diagnosis, thyroid cancer could soon represent up to 10 percent of all cancer survivors in the United States, they predicted.
“The increase that we’ve seen in the U.S. we’ve seen in a number of countries worldwide,” Aschebrook-Kilfoy said. “And, even in lower incidence countries, you see a similar gender disparity.”
Because patients face good outcomes, very few studies have been conducted looking at thyroid cancer survivorship. Two years ago, after seeing clinic patients express survival concerns firsthand, Aschebrook-Kilfoy and Grogan decided to address this gap in data.
Beginning in October 2013, they recruited 1,174 thyroid cancer survivors – 89.9 percent female with an average age of 48 – from across the United States and Canada. Participants were recruited through the thyroid cancer clinics at the University of Chicago Medicine, and the clinics of six other universities, as well as through thyroid cancer survivor support groups and social media.
The researchers then used City of Hope’s Quality of Life thyroid tool, a questionnaire that assesses physical, psychological, social and spiritual wellbeing on a 0-10 scale, to measure patient-reported quality of life. They found that thyroid cancer survivors reported worse quality of life, with an average of 5.56 out of 10, than the mean quality of life score of 6.75 reported by survivors of other cancer types (including colorectal and breast) that have poorer prognoses and more invasive treatments.
“I think we all have this fear of cancer that has been engrained in our society,” Grogan said. “So, no matter what the prognosis is, we’re just terrified that we have a cancer. And, I think this shows that.”
After treatment, thyroid cancer survivors face a lifetime of cancer surveillance and an anxiety inducing high rate of recurrence, which could contribute to their findings.
Aschebrook-Kilfoy and Grogan also found that patients who were younger, female, less educated and those that participated in survivorship groups all reported even worse quality of life than other study participants. However, after five years of survival quality of life gradually starts to increase over time in both women and men.
The researchers, whose findings are featured in the December issue of the journal Thyroid, will continue to track study participants in order to further understand this illuminating data.
“The goal of this study is to turn it into a long-term, longitudinal cohort,” said Grogan, who hopes to develop a tool that physicians can use to assess the psychological wellbeing of thyroid cancer survivors. Psychological wellbeing is part of the Institute of Medicine’s recommended survivorship care plans. “But, there was no way to do that with thyroid cancer because no one had ever studied quality of life or psychology of thyroid cancer before,” he said.
Both researchers believe the rise in thyroid cancer incidence could be due in part to more advanced imaging tools that catch cases that might have otherwise gone undiagnosed, as well as emerging environmental and lifestyle risk factors.
“Radiation exposure is one of the main risk factors that is known to cause cancer of the thyroid,” Grogan said. “One environmental hypothesis is that ultra-low doses of radiation over decades could cause some type of change in the thyroid.”
“Another common environmental hypothesis is environmental endocrine system disruption,” Aschebrook-Kilfoy said. The body’s endocrine system is made up of glands (like the thyroid) that secrete hormones into the bloodstream. Pesticides and other chemicals in the environment have been shown to affect thyroid hormone levels, an area where Aschebrook-Kilfoy has focused much of her research. “Along with that there is literature that shows there’s an increased risk of thyroid cancer with people who are obese,” she said.
Other studies have even shown that proximity to volcanic activity (living in a certain region on the Italian island of Sicily, for example) correlates with an increased risk for the disease. But, scientists are still not sure why. Aschebrook-Kilfoy and Grogan have begun to collect biospecimens and DNA samples from patients, which can be used to further study environmental and genetic risk factors that may account for the increase.
Both researchers hope this study will demonstrate the importance of studying survivorship, especially in thyroid cancer, which may have better patient outcomes but is far from “good.”