Abstract
Introduction: Lung cancer is the leading cause of cancer related deaths in the United States. Impact of race on prognosis of lung cancer has been controversial. We performed a retrospective study to evaluate if survival differences exist in patients of different races diagnosed with lung cancer and potential causes of these differences, if they exist.
Methods: Data on patients diagnosed with lung cancer from 2003-2008 were collected from the Cancer Information Resource File (CIRF). Of 150,038 patients, complete data on age, gender, stage, histology, radiation therapy, chemotherapy, surgery and survival were available on 130,517 patients. Data were analyzed according to race and grouped into three categories: white, black, and other races (all non-white and non-black patients).
Results: Of 130,517 patients evaluated, 91.4% were white, 6.5% were black, and 2.1% were other races. Within each race category, the percentage of patients less than 70 years of age were 54,67, and 59, and male patients were 55,58, and 56 in white, black, and other races, respectively. Non small cell lung cancer was found in 83.3,87.7, and 86.6%, small cell lung cancer was found in 16.3,12, and 12.9% and mixed histology lung cancer was found in 0.4,0.3, and 0.5% in white, black, and other races, respectively. The percentage of patients with stage I was 23,19, and 21; stage II was 7,6, and 5; stage III was 29,31, and 30; and stage IV was 41,44, and 44 in white, black, and other races, respectively. The percentage of patients receiving chemotherapy was 44, 43, and 45; radiation therapy was 49,52, and 45; and surgery was 28, 21, and 28 in white, black, and other races, respectively. Median overall survival (MOS) in months was 10.3,9.1, and 11.8 in white, black, and other races, respectively. On multivariate analysis, factors affecting overall survival were age greater than 70 [hazard ratio (HR) 1.3], male gender (HR 1.2), chemotherapy (HR 0.57), surgery (HR 0.37), radiation therapy (HR 0.9), and bronchoalveolar (BAL) histology (HR 0.69). Race was an independent risk factor for other races compared to white patients (HR 0.86, CI 0.83-0.90), but not for black compared to white patients (HR 1.01, CI 0.98-1.03).
Conclusion: Race is not an independent prognostic factor for overall survival for black patients, but was a better prognostic factor for other races when compared to white patients. A higher percentage of black patients presented at a later stage and a lower percentage received surgery, and these factors may have contributed to a lower MOS compared to whites and other races. BAL histology had a favorable prognosis than other histologies. Prospective, randomized clinical trials are required to explore differences noted in MOS, stage, and histology according to race.
Citation Information: Cancer Epidemiol Biomarkers Prev 2010;19(10 Suppl):B78.