Patients who are diagnosed with Hodgkin lymphoma between the ages of 15 and 39 are less likely to survive the disease if they are black, Hispanic, or live in a neighborhood with low socioeconomic status, according to a study published in Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Association for Cancer Research.
"Hodgkin lymphoma is thought of as a curable cancer," said lead author Theresa H.M. Keegan, PhD, MS, associate professor in the Division of Hematology and Oncology at the UC Davis Comprehensive Cancer Center in Sacramento, California. "However, the impressive survival gains have not been shared uniformly across the adolescent/young adult [AYA] population."
Keegan and colleagues studied data from 9,353 patients in the California Cancer Registry who were between 15 and 39 years old when they were diagnosed with Hodgkin lymphoma between 1988 and 2011. They examined the impact of race/ethnicity, neighborhood socioeconomic status (SES), and health insurance.
The researchers found that AYAs diagnosed with early-stage Hodgkin lymphoma were twice as likely to die if they resided in a lower SES neighborhood. They were also twice as likely to die if they had public health insurance or were uninsured, regardless of whether they were diagnosed at an early stage or a late stage.
Disparities existed between race/ethnicities as well, Keegan noted. Black AYA patients were 68 percent more likely to die of the disease than non-Hispanic white patients, whether they were diagnosed at an early stage or a late stage. Hispanic AYA patients diagnosed at a late stage were 58 percent more likely than non-Hispanic white patients to die of Hodgkin lymphoma; there was not a significant disparity for Hispanic patients diagnosed at an early stage.
Keegan said patients from lower SES neighborhoods faced obstacles at several stages of their illness. First, AYAs who were uninsured, had public health insurance, or resided in lower SES neighborhoods were more likely to be diagnosed with advanced-stage Hodgkin lymphoma.
Also, much of the success in improving survival from Hodgkin lymphoma has been due to "combined-modality" treatment, which involves chemotherapy and radiation. The researchers found that black and Hispanic patients were more likely to receive chemotherapy only, although it was not clear why their treatment differed.
Finally, Keegan said, some patients who may have initially been declared cancer-free may not have continued medical care, leaving them susceptible to secondary cancers or other complications and late effects. "Identifying and reducing barriers to recommended treatment and surveillance in these AYAs at much higher risk of mortality is essential to ameliorating these survival disparities," Keegan said.
Keegan noted that the study subjects were mostly diagnosed before implementation of the Affordable Care Act, which went into effect in 2010. She noted that before the Affordable Care Act the AYA population was especially vulnerable to losing insurance, as many aged out of their parents' plans, were changing jobs or looking for jobs, felt that they were too healthy to need insurance, or could not afford to purchase insurance on their own. She expects that a similar study conducted now would show higher rates of insurance coverage. "Future research will determine whether that translates into improved survival outcomes," she said.
Keegan noted some limitations of the study. Researchers were able to identify the first course of treatment, but did not have specific details of treatment that followed the initial period. Also, health insurance status at the time of diagnosis was not available for patients who were diagnosed before 2001, and the researchers did not have information on changes in patients' insurance status that may have occurred after their initial treatment.
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