Exposure to air pollution could negatively affect your chanes of survival if you have lung cancer, a new study is claiming. This is particularly true for patients who are in the early stages of the disease, and especially for those with adenocarinoma, the most common form of lung cancer making up 80 percent of cases, according to a BMJ statement.

The study was based on more than 352,000 patients with newly diagnoses lung cancer who had a higher exposure than normal to nitorgen dioxide. They found an increased risk of death of about 38 percent, depending on the cancer stage and what kind of pollutant was involved, indicating that reducing one’s exposure to pollution could increase their chances of survival from lung cancer.

Scientists were quite surprised at the finding, as until now the scientific community hadn’t thought that air pollution might have a significant impact on lung cancer survival. But the study found that pollution has different impacts depending on the stage and histology at diagnosis, and the effects were the strongest on those with the highest survival rate.

“Air pollution has been linked to a higher incidence of lung cancer and death, but little is known about its potential impact on an individual’s chances of survival after diagnosis,” the statement reads. “In a bid to clarify this, the researchers tracked the health outcomes up until the end of 2011 of more than 352,000 people newly diagnosed with lung cancer between 1988 and 2009, and whose details had been entered into the US California Cancer Registry. Their average age at diagnosis was 69. More than half (53%) of the cancers were diagnosed at an advanced stage (distant spread); and the average survival time for localised (early stage) disease was 3.6 years, falling to 1.3 years for regional spread, and just 4 months for distant spread. For patients with early stage disease, average survival time was shortest for those with small and large cell cancers (around 1.5 years) and longest for those with adenocarcinoma (around 5 years).”