2-fold breast cancer risk increase

JoTheGreek

Since my benign diagnosis in July 2018 (adenosis, apocrine metaplasia, usual type of ductal epithelial hyperplasia with no
further categorization as mild, moderate, etc. stated in the histology report)
I’ve wanted to ask a question and get an answer to it from someone in the know as,
apparently, my math skills are quite insufficient when it comes to calculating percentages lol.  Having in mind that any
woman’s lifetime breast cancer risk is 12% what does it mean a 2-fold increase
for those with moderate ductal hyperplasia? Does it mean 24%, 36% or 48%?  The question may sound stupid but I really
can’t figure out which one is the correct one. Thanks so much to anyone who can answer this
query for me.

MelissaDallas

Have you discussed it with your doctor? Most of those conditions are essentially just related to having benign fibrocystic breasts and to my knowledge confer little, if any, additional risk, so not sure how you are coming up with those numbers. I have LCIS, which IS a considerable risk factor, but geneticist said probably only 20-25%, so lower than what you are coming up with lesser conditions.

JoTheGreek

Thank you so much for your response.  To be honest I've never discussed this subject with my doctor (ob/gyn specialized in breast surgery) mainly because my histology report didn't contain any info on the gravity of hyperplasia (mild, moderate, e.tc) other than it isn't atypical (usual type), so I assumed that he wouldn't have a clear idea as to if I am at a higher risk of developing bc in the future.  But I do read online that moderate usual ductal epithelial hyperplasia poses a 2-fold increase on the bc risk factor and I was wondering if that means 24% or higher.  From your response I assume that at least it's not higher than 24% and thank you for taking the time to respond. 

Ingerp

I'm sure it's the 24% figure, but let me just tell you to keep up with your regular mammos. I had ALH about 10 years ago and somehow several years later was about 18 months late with my mammo when I got the 2016 DCIS diagnosis. I don't think doing the mammo on time would have changed the diagnosis, but I do believe the area affected would have been smaller. Somehow nobody ever impressed on me that getting the ALH dx increased my odds of eventually getting breast cancer. Make sure you get in there to take a look every year.

MelissaDallas

This says usual, as opposed to atypical, confers minimal to none:

https://www.breastcancer.org/symptoms/benign/usual-hyperplasia

JoTheGreek

Thank you, my ladies! I'll defo never skip another yearly mammo and ultrasound ever again.  Mind you (and I'm not at all proud for confessing that) I haven't had a mammo for 6 years (between 2012 and 2018) and when I finally went to have my breasts checked in June 2018 the radiologist was pretty convinced she was looking at a small yet aggressive carcinoma tightly clung to the major thoracic muscle... I learned my lesson well, the hard way...

MelissaDallas

Jo, I sincerely believe that if the doctor had been concerned that any of these findings put you into a high risk category they would definitely be discussing it with you. I just don't think they do, which is a good thing. I got a similar biopsy report and was pretty much told fibrocystic/aging breasts.

Beesie

"Having in mind that any woman's lifetime breast cancer risk is 12% what does it mean a 2-fold increase for those with moderate ductal hyperplasia? Does it mean 24%, 36% or 48%?"

None of the above.

It is true that on average, an individual woman has a 12% chance of developing breast cancer over her lifetime (to about age 80), but this 12% average includes all women, some who are low risk but also all of those who are very high risk (those who are BRCA positive, for example).

What this means is that none of us individually actually have this 12% risk. It's just an average for all women, a guide post used to gauge whether an individual's risk is below average, about equal to average, or above average and possibly 'high risk'. To figure out our own individual risks, we all start off with the same relatively low 'base risk', which is the breast cancer risk we all face just because we are women. Then our own individual risk factors are added on top. This provides you with your own risk level, not a risk level based on the entire population of women.

It's been years since I've looked into it, but my recollection is that base risk is somewhere in the range of 4% - 5%. If you've been found to have a condition that presents a 2-fold increase in risk, this means that your personal risk, without consideration to any other risk factors you may have, would now be in the range of 8% - 10%, a doubling of your base risk. If you don't have any other conditions that increase breast cancer risk, this means that even with usual ductal epithelial hyperplasia, your risk might still be less than that of the 'average' woman.

This is why low level risk factors are not usually considered to be a concern, unless an individual has other more significant risk factors as well. These low risk factors are common conditions that many women develop that simply move them up from base risk into the range of the average risk, but do not put them anywhere near a 'high risk' category.

JoTheGreek

Thank you so much!  Very informative post, I guess I had it all wrong in my mind up to now.