Substantial variation in treatment patterns can explain geographic differences in survival outcomes in patients with lung cancer, according to a new study conducted in the United Kingdom.
“Survival from lung cancer has been lower in England than in comparable countries,” wrote study authors led by Henrik Møller, MD, of King’s College London. “There remain important variations in lung cancer outcomes linked to region of residence, hospital of first attendance, socioeconomic position,” and other factors. The authors aimed to evaluate the magnitude of treatment variation among regions of England, in order to potentially identify opportunities to improve outcomes.
They conducted a detailed analysis of the records of 176,225 lung cancer patients diagnosed from 2010 to 2014. More than half of the cohort (54.6%) were male, and stage IV disease was seen most commonly (43.6%) Results of the analysis were published in Thorax.
They first showed in a larger group dating back to 2005 that lung cancer survival in general has been improving steadily; the 1-year survival estimate rose from 26% in 2005 to 36% in 2014.
The primary analysis showed substantial variation by geography in treatments used. Surgical resection varied from 9.3% of patients in the lowest quintile, up to 17.2% in the highest quintile. For radical radiotherapy, the range was 4.0% to 12.9%, and for chemotherapy it was 21.6% to 34.5%.
The highest geographic quintile for surgical resection had lower all-cause mortality than the lowest quintile; after adjustment for age and sex, the hazard ratio (HR) was 0.84 (95% CI, 0.83–0.86). The authors noted that the statistical trend across the five quintiles was highly significant. If all areas used surgical resection at the rate of the highest quintile, approximately 188 deaths per year could be avoided at the 2-year survival time point.
For radical radiotherapy, there was a trend toward better survival in the highest quintile compared with the lowest, with an HR of 0.94 (95% CI, 0.92–0.95); a total of 373 deaths per year at the 2-year time point could be avoided with the highest quintile’s level of treatment. For chemotherapy, the HR for survival was 0.90 (95% CI, 0.88–0.91), and the number of avoidable deaths at 6 months was 318.
“The data suggest important improvement in lung cancer survival over time, but there is potential for further survival gains if the use of active treatments in all areas could be increased toward the highest current regional rates,” the authors wrote. “The mechanisms required to achieve this range from improving access to more specialized lung cancer multidisciplinary teams, to increasing the number of specialist thoracic surgeons.”