Poor outcomes more common among minority populations with NSCLC
Black and American Indian patients with stage I non–small cell lung cancer had higher rates of overall and cancer-specific mortality than white patients, a disparity that has persisted over time, according to results of a SEER analysis presented at the Multidisciplinary Thoracic Cancers Symposium.
Although there is greater availability of potentially curative treatments for early-stage NSCLC, black and American Indian patients were less likely to receive these curative treatments, results also showed.
“These findings bring attention to the importance of the medical system actively addressing disparities on pace with advancements in medical science,” Andrew M. Farach, MD, radiation oncologist at Houston Methodist Hospital, said during a press conference.
NSCLC is the most common malignancy, with only approximately a quarter of patients diagnosed at an early and curable stage, Farach said.
“The purpose of our study was to understand if racial disparities in the treatment and outcome of stage I non–small cell lung cancer have diminished, given the increased adoption of the advancements in its treatment,” Farach said.
The researchers used the SEER database to identify 62,312 patients diagnosed with stage I NSCLC between 2004 and 2012. All patients were aged older than 60 years and divided into cohorts based on racial subsets: white (86.6%), black (8%), Asian/Pacific Islander (5%), American Indian (0.3%) and unknown (0.02%).
Patients underwent surgery only (67%), radiation only (19%), surgery and radiation (3%) or no therapy/observation only (12%).
The treatment patients received varied by race. Sixty-seven percent of white patients and 72% of Asian/Pacific Islander patients underwent surgery compared with 56% of black patients and 58% of American Indian patients (P < .05).
“About two-thirds of patients with stage I disease received surgery in the overall population,” Farach said. “However, there was significant discrepancy of the utility of surgery in both the black and American Indian populations.”
Further, 18% of black patients received no treatment.
“We find that a 12% [nontreatment rate] overall for stage I disease is a pretty high number, so if you increase that to one in five patients, it is a dramatic impact on the outcome for these patients,” Farach said.
Analyses also showed that black and Asian/Pacific Islander patients were more like to receive radiation than surgery.
At a median follow-up of 23 months, OS curves showed Asian/Pacific Islander patients had the highest OS (76%) followed by white patients (70%), black patients (65%) and American Indians (60%; P < .05).
Cancer-specific survival also was highest for Asian/Pacific Islander patients (84%) followed by white patients (79%), black patients (76%) and American Indians (73%; P < .05). Median cancer-specific survival was 80 months for blacks and 49 months for American Indians, but 107 months for the overall population (P < .05).
“It was striking to see that African Americans’ median cancer-specific survival was only 80 months — more than 2 years lower than the standard patient with early-stage lung cancer — and the American Indian population was even more dramatic, with survival more than 5 years shorter than the general cohort,” Farach said.
Multivariate analysis showed, compared with white patients, cancer-specific survival was lowest for American Indians (HR = 1.35) and highest among Asian/Pacific Islanders (HR = 0.77).
Risk factors for poor outcomes include male sex, older age and stage T2 tumors. Favorable factors include receiving definitive therapy and Asian/Pacific Islander race.
“Importantly, if African American patients were taken to definitive therapy, the difference in survival was removed as a risk factor for worst outcomes,” Farach said. “So, if we can get them the treatment, they will do just as well as the Caucasian counterparts.”
The results showcase disparities and the need to provide access to care to minority populations, according to Pranshu Mohindra, MD, assistant professor in the department of radiation oncology at University of Maryland School of Medicine.
“This study brings to light racial disparities in the use of modern treatment, the cause of which is most likely multifactorial,” Mohindra, who was not involved in the study, said during the press conference. “While the study does not directly provide clinical practice altering results, it significantly highlights the need to provide access to care for the blacks and minority groups.” – by Melinda Stevens
Dalwadi SM, et al. Abstract 9. Presented at: Multidisciplinary Thoracic Cancers Symposium; March 16-18, 2017; San Francisco.
Disclosures: The researchers report no relevant financial disclosures. Mohindra reports no relevant financial disclosures.