The Journal of the National Cancer Institute recently had a study which looked specifically at non-Hispanic white men and women. Cook, et al, wanted to evaluate the impact of smoking and then smoking cessation on the risk of adenocarcinoma of the esophagus.
I wanted to write about this topic because of the story about Michael Douglas, the long time actor who has come out this last week to let the world know that he has Stage 4 throat cancer. The actor did quit smoking a couple of years ago, back in 2006, but was self-described as a heavy smoker prior to his quitting. I'm not sure what kind of cancer Mr. Douglas has, but I can make a bet that it is some how related to his previous smoking habit. The study, Cigarette Smoking and Adenocarcinomas of the Esophagus and Esophagogastric Junction: A Pooled Analysis From the International BEACON Consortium, found a correlation between esophagus adenocarcinoma and smoking. They also found a very strong correlation between smoking and the risk for developing esophagogastric junction adenocarcinoma along with all adenocarcinomas.
In addition, there was a strong dose-response link betweek heaviness of smoking and outcome. This is based on a term we use called pack-years. Pack-years is a method healthcare professionals use to quantitate how heavy someone smokes. You take the number of packs per day they smoke on average and multiply by the number of years they smoked. So if someone smoked about 1 pack per day for 40 years then they have a (1 X 40 = 40) 40 pack-year history. This helps us compare smokers to other smokers, apples to apples as it were.
It is evident that the longer someone was smoke-free, the less risk for developing adenocarcinoma of the esophagus they had, after adjusting for pack-years. For example, current smokers had the highest risk (odds ratio of 0.82), while those who quit 10 years ago had a lower risk (odds ratio 0.71). These differences in risk were seen in both men and women.
This is yet another unbiased study which details that smoking is bad for you. I still marvel at people who think this stuff is all made up. Those folks are in some serious denial.
