Can anyone understand the Risk % in Lung Cancer studies?

[Steph74]

I read this 2006 MD Anderson study - I'm confused and wonder if anyone can explain to me. I know the regular risk of lung cancer in women is 1 in 16 - so about 6%, does this article state that my risk is now 68% (being a first degree relative to a lung cancer never smoker)?!? I'm not sure if this is relative or absolute risk. I pray I'm not reading this correctly. Any insight would be helpful..(link to article is below)

Study Demonstrates Lung Cancer Susceptibility Runs in Families of Patients that never smoked

They discovered:

* First-degree relatives of cases had a 25 percent increased risk of developing any type of cancer, compared to controls. Cancers diagnosed in the relatives include melanoma, colorectal, head and neck cancer, lung, prostate and breast cancers.

* Case relatives were about 10 years younger when they were diagnosed with cancer, compared to control relatives.

* A 44 percent excess risk of young onset cancers - those diagnosed before age 50 - among case relatives.

* More than a six-fold risk of developing young onset lung cancer in the case families compared to control families.

* Relatives of case patients had a 68 percent increased risk of developing lung cancer.* Mothers of case patients had more than a two-fold risk of developing breast cancer.

http://www.mdanderson.org/departments/n ... 508b603a14

[raneyf]

I don't know, but wish someone could interpret. If that's the case, I wonder what my kids risks are, since I was diagnosed young and a never-smoker. Maybe I should ask the pediatrician for spiral ct's.

[wondermom]

I am not sure either. I have heard varying numbers. I am going to ask my doctor about it during my physical on Friday. I am also asking to start yearly chest x-rays as my Mom is a never smoker who has lung cancer. I am definately concerned for my siblings and my risk.

[Don M]

Well, I am not an expert biometrician or any thing, but I think I understand it.

It is a relative risk since two groups are being compared. It means that for the 2 given populations one group is 68% more likely to get lung cancer compared to the other group. This speaks to the population as a whole only and not any individual anywhere that has a never smoking relative that got lung cancer. I think it is safe to say though, that you are more likely to get cancer than someone who does not have a first-degree relative that never smoked and got lung cancer.

Don M

[neilb]

It means that you would have a 68% greater chance of developing lung cancer than someone in similar circumstances (they probably controlled for smoking history of the first-degree relatives). For instance, if (and I'm making this number up), a non-smoking woman has a 3% chance of ever developing lung cancer, your chances would be 68% greater than that, which be 3% + (68% of 3%). So, your chances would be 5% instead of 3%. I hope that reassures you some.--Neil

[Nick C]

Yeah, it isn't a 68% chance it will happen, you are 68% more likely.

So mathematically:

If the chance of SOMETHING happening is 1/16 that is a 6.25% chance.

If you are 68% more likely because of some OTHER factor, then there is a 10.5% chance of this SOMETHING happening. (.0625 X 1.68)

That's the math.

As far as studies go and whatnot...who knows.

There are always variables not taken into account.

[Lee and Chi]

I have been wondering the same thing. Not only did my Mom develop lung cancer at an early age as a non smoker, but so did my great grand mother on the same side. She passed away around the same age from this disease.

However, BOTH my grandmother and her sister are in their mid 80's and they both smoked for around 30+ years and neither one of them has lung cancer. Also, my mother has an older brother who is a non smoker with no cancer.

So I guessed it just decided to skip a generation? Or half of one? I really have no idea. But it shows you at least that studies are just guesses in the dark as to what is going to happen to us "at risk" folks. I am going to be more vigilant and have routine chest x-rays. If I think about it too much I start to panic, and I can't live in fear of this for the rest of my life! I'm determined to make it to 100!