Survivors of thyroid cancer who were diagnosed when aged younger than 40 years appeared at increased risk for various diseases associated with aging, including heart disease and osteoporosis, according to a study scheduled for presentation at the Cancer Survivorship Symposium.
“Patients diagnosed with thyroid cancer often have an excellent prognosis and survival rate, especially those diagnosed at younger ages ... but as the number of thyroid cancer survivors grows, more people are living with other serious health conditions resulting from treatment,” Brenna Blackburn, MPH, member of the Hashibe Lab at Huntsman Cancer Institute, and a PhD candidate at University of Utah, said during a press conference. “It is important to understand these long-term risks so that we can not only help manage their health, but also inform how oncologists care for these patients from the onset of diagnosis.”
Blackburn and colleagues reviewed data from patients in the Utah Population Database who were diagnosed with thyroid cancer between 1997 and 2012. Survivors were matched with up to five cancer-free controls based on birth year, sex, birth state and follow-up from case diagnosis date.
The analysis included data from 1,365 survivors matched with 6,043 controls aged 40 years and younger, and 2,341 survivors matched with 9,544 cancer-free controls aged 40 years and older.
Electronic medical records and statewide ambulatory surgery and inpatient discharge data were used to determine late effects of thyroid cancer over three time periods: 1 to 5 years, 5 to 10 years and more than 10 years after diagnosis.
Risk for hypertension within 1 to 5 years after diagnosis appeared greater in survivors diagnosed with thyroid cancer before 40 years of age (HR = 2.32; 95% CI, 1.83-2.94) and after 40 years of age (HR = 1.68; 95% CI, 1.54-1.84). The risk for hypertension also was higher in both younger (HR = 1.54; 95% CI, 1.18-2.01) and older survivors (HR = 1.3; 95% CI, 1.11-1.53) more than 10 years after diagnosis.
Younger survivors appeared more likely to develop osteoporosis 1 to 5 years after diagnosis (HR = 7.56; 95% CI, 2.74-20.91) than were older survivors (HR = 2.34; 95% CI, 1.95-2.8).
Younger survivors had increased risks for developing pericarditis, endocarditis and myocarditis (HR = 5.12; 95% CI, 1.04-25.14) and heart valve disorders (HR = 2.43; 95% CI, 1.36-4.33) more than 10 years after diagnosis. The corresponding HRs for older age groups did not reach statistical significance.
“This group [of survivors] had significant risk increases, but not as high as the younger diagnosed population,” Blackburn said.
Blackburn further explained that the thyroid cancer survivors diagnosed before 40 years of age had increased risks for these diseases, but experienced them at lower frequencies.
“For instance, 1.1% of those diagnosed before age 40 had osteoporosis compared with 9.6% of those diagnosed with osteoporosis at age 40 or older in the same time period,” Blackburn said, adding that part of the explanation may be because younger patients are receiving more aggressive treatments.
“Prolonged exposure to treatment or side effects to treatment may lead to higher rates of long- term health problems in younger diagnosed thyroid cancer survivors,” Blackburn said. “It is important to remember that thyroid cancer is a young cancer with very high survival. It is a population living a long time after diagnose, so understanding late effects can lead to better surveillance and disease management.”
The study is important and “underscores” the need for personal survivorship care and what areas clinicians should focus on, Merry Jennifer Markham, MD, associate professor in the division of hematology and oncology at University of Florida Health, and an ASCO expert, said during the press conference.
“The reality is that many patients with thyroid cancer are treated successfully and do live very long lives after cancer and treatment, but we still don’t know enough about how treatment affects survivors later in life,” Markham said. – by Melinda Stevens
Blackburn B, et al. Abstract 111. Scheduled for presentation at: Cancer Survivorship Symposium: Advancing Care and Research; Jan. 27-28, 2017; San Diego.
: Blackburn reports no relevant financial disclosures. Please see the abstract for a list of all other researchers’ relevant financial disclosures.