NEW YORKFewer blacks than whites receive potentially curative surgery for early stage lung cancer, and this disparity is substantially responsible for lower survival rates for black patients, according to researchers at Memorial Sloan-Kettering Cancer Center and the National Cancer Institute.
In our study, black men and women were 13% less likely to have surgery for early stage lung cancer, and this translated into lower overall survival. It is a phenomenon that appeared independent of socioeconomic status, said Peter B. Bach, MD, first author of the study and an epidemiologist at Memorial Sloan-Kettering. We believe that fewer blacks will die of this disease if more receive the best available treatment.
The researchers analyzed data from nearly 11,000 patients age 65 and older who were diagnosed with early stage non-small-cell lung cancer (NSCLC).
Treatment of early stage NSCLC was chosen for analysis because surgery offers the possibility of cure. The optimal strategy is unambiguous, Dr. Bach said. An average of 40% of patients undergoing surgery are alive after 5 years vs only 5% of patients who do not have surgery.
Dr. Bach and his colleagues looked at the experience of 10,984 Medicare patients diagnosed with stage I or II non-small-cell lung cancer between 1985 and 1993; 860 (8%) were black, and 10,124 (92%) were non-Hispanic white. The patients all lived within one of 10 regions included in the NCIs Surveillance, Epidemiology and End Results (SEER) database. All were covered by Medicare, either through an HMO or a traditional indemnity plan.
By linking Medicare and SEER data, the researchers were able to obtain comprehensive information about each patient, including diagnosis, coexisting conditions, treatment, availability of health care, and patient demographics.
The researchers found that 64% of the black patients in the study underwent surgery, compared with 76.7% of the white patients (P < .001).
This disparity translated into higher overall mortality for blacks. At 5 years, 26% of the black patients were still alive, compared with 34% of the white patients (N Engl J Med 341:1198-1205, 1999). If whites and blacks were to receive surgical treatment equally, the authors estimate that the survival of black patients would rise to 31%.
Five-year survival rates were comparable for blacks and whites who received surgery (39.1% and 42.9%, respectively, P = .10), and for blacks and white who did not undergo surgery (4% and 5%, respectively, P = .25).
Because the study did not examine the reasons why black patients undergo surgery less frequently, it is difficult to know why this disparity exists, Dr. Bach said. One explanation could be that blacks are not offered the surgery as frequently; another is that they are choosing not to have surgery.