Disparities and Trends in Genetic Testing and Erlotinib Treatment among Metastatic Non–Small Cell Lung Cancer Patients

Abstract

Background: Despite reports of socioeconomic disparities in rates of genetic testing and targeted therapy treatment for metastatic non-small cell lung cancer (NSCLC), little is known about whether such disparities are changing over time.Methods: We performed a retrospective analysis to identify disparities and trends in genetic testing and treatment with erlotinib. Using the Surveillance, Epidemiology, and End Results (SEER)-Medicare database, we identified 9,900 patients with stage IV NSCLC diagnosed in 2007 to 2011 at age 65 or older. We performed logistic regression analyses to identify patient factors associated with odds of receiving a genetic test and erlotinib treatment, and to assess trends in these differences with respect to diagnosis year.Results: Patients were more likely to receive genetic testing if they were under age 75 at diagnosis [odds ratio (OR), 1.55] independent of comorbidity level, and this age-based gap showed a decrease over time (OR, 0.93). For untested patients, erlotinib treatment was associated with race (OR, 0.58, black vs. white; OR, 2.45, Asian vs. white), and was more likely among female patients (OR, 1.45); for tested patients, erlotinib treatment was less likely among low-income patients (OR, 0.32). Most of these associations persisted or increased in magnitude.Conclusions: Race and sex are associated with rates of erlotinib treatment for patients who did not receive genetic testing, and low-income status is associated with treatment rates for those who did receive testing. The racial disparity remained stable over time, while the income-based disparity grew larger.Impact: Attention to reducing disparities is needed as precision cancer treatments continue to be developed.

Are there socio-economic inequalities in utilization of predictive biomarker tests and biological and precision therapies for cancer? A systematic review and meta-analysis

“…1) and were included in the review. Eight studies reported utilization data for predictive biomarker tests [21][22][23][24][25][26][27][28], thirty-seven studies (41 papers) reported utilization data for biological and precision therapies , and 3 studies reported both [66][67][68]. Ten papers (Additional file 1: Table S1) had no denominator populations or only reported an average measure of socio-economic status (e.g., mean household income), and were excluded from inclusion in the meta-analysis and are not discussed further [69][70][71][72][73][74][75][76][77][78].…”

“…The 48 included studies covered 7 cancers, 5 predictive biomarker tests, and 11 biological and precision therapy classifications, of which bevacizumab (12 studies) [ 41 – 45 , 54 – 56 , 58 , 59 , 64 , 65 ] and trastuzumab (11 studies) [ 29 – 39 ] were most common. Most studies were in the USA ( n = 42) [ 21 , 22 , 25 – 35 , 40 – 68 ], and a majority analyzed SEER registry data ( n = 27) [ 21 , 22 , 25 , 29 – 33 , 41 , 42 , 45 , 47 , 49 , 50 , 54 – 59 , 61 – 64 , 66 – 68 ] (Additional file 1 : Fig. S1).…”

“…The remaining studies were from Canada (4 studies) [23,[36][37][38], China (1 study) [39], and Ireland (1 study) [24]. Forty-six studies reported one or more area-based socio-economic status measure, and only two utilized individual-based measures [34,68]. Six SES measures (poverty, income, education, employment, deprivation, and socio-economic status aggregate score) were reported.…”

“…Eleven studies reported data of interest for five predictive biomarker tests [21][22][23][24][25][26][27][28][66][67][68]. Ten studies were included in the meta-analysis [21-28, 66, 68].…”

“…Nine lung cancer studies evaluated socio-economic status with biological and precision therapy receipt [41-47, 67, 68]. Four of these reported bevacizumab [41][42][43][44], 2 tyrosine kinase inhibitors [67,68], 1 both bevacizumab and tyrosine kinase inhibitors [45], 1 immunotherapy [46], and 1 biological therapies (mostly bevacizumab) [47]. Six were eligible for meta-analysis [42,[44][45][46][47]68], and the pooled OR for receipt of biological and precision therapies in those of low compared to high socioeconomic status was 0.71 (95% CI 0.51-1.00; I 2 = 95%) ( Fig.…”