Despite increased spending on lung cancer treatment, average life expectancy among elderly sufferers of the disease in the U.S. rose very little during a 14-year study period, new research suggests.

A study found that between 1983 and 1997, costs per patient aged 65 and older rose by more than $20,000 per patient, while the average life expectancy of those patients increased by less than one month.

"The additional money spent on lung cancer treatment in the mid-1990s compared to in the early 1980s did not result in a favourable economic rate of return by conventional benchmarks," write the authors.

The study was conducted by researchers at Harvard University, the U.S. National Cancer Institute and the U.S. National Bureau of Economic Research. The findings are published in the December 1, 2007, issue of the journal Cancer.

According to the Canadian Cancer Society, in 2007, an estimated 23,300 Canadians will be diagnosed with lung cancer and 19,900 will die of it. Lung cancer incidence and mortality rates continue to climb among women while decreasing among men.

According to the study, lung cancer patients have an 85 per cent chance of dying of the disease in the first five years.

The study found the cost-effectiveness of increased investment in treating the disease among the elderly — who account for over fifty per cent of cases — was poor. Researchers found that early-stage cancer treatment was more cost-effective than treatments for advanced lung cancer.

The cost-effectiveness ratio (the cost of treatment to an additional year of life) was $143,614 for localized lung cancer (a cancer that is confined to one area of the lung), $145,861 for regional cancer (a cancer that has spread within the lung but is contained within it) and $1.2 million for metastatic cancer.

"Almost all gains in survival have been in localized-cancer cases," read the study. "Life expectancy has improved by one fifth of a year for localized cancer cases and has not increased appreciably for distant-cancer cases."

The researchers attribute the improvements in localized treatment to better surgical technique and improvements in perioperative care.

The authors suggest that given the high percentage of lung cancer patients who are smokers, spending more money on smoking prevention and cessation programs may be a more promising approach.