What do you think causes breast cancer?

ChiSandy

Cliff, both men's and women’s bodies make an androgen (androstenedione, the same stuff Sammy Sosa & Mark McGwyre took during their home run wars) via our fat cells and adrenal glands. Our livers make aromatase, which converts andro to the estrogen estradiol. This is because for most people, having some degree of circulating estrogen is beneficial (cardioprotective, slows progression of or even prevents bone loss). Unfortunately, in some people it also causes those few rogue estrogen-sensitive breast cells to decide they want to be immortal instead of die off like they’re supposed to, and so they keep dividing—et voilà: tumor. The reason it happens less often in men is that men don’t have lifelong exposure to higher levels of estrogen from that secreted by ovaries, birth control pills, shorter menstrual cycles, longer-than-normal childbearing years (early menarche/late menopause), etc. And the risk is higher for women who either never give birth, gave birth late in life (>30) and had only one or two children and didn’t breastfeed. Tick all of the above for me—except I did breastfeed my son for about 6 weeks. But my mom had just as early a menarche and as late a menopause, had me at 31 and my sis at 33, and bottle-fed us both from day one…and she never got breast cancer.

The incontrovertible risk factors are making it to adulthood & beyond, and having breasts. Yet, except for those with family history and genetic mutations, women have only a 12% chance of developing it by age 80, and men have less than one-tenth that probability. You, like us, drew the short straw.

Optimist52

ChiSandy, "you drew the short straw" was my surgeon's answer to why I might have got BC twice when we drew up my family tree with a lot of my relatives living until their late 80s and 90s. She knows a lot about genetics and that was her educated conclusion.

I breastfed my two sons for a total of nine years without a break, yes years not months, as I belonged to La Leche League and was practising child-led weaning. This is supposed to be very protective against breast cancer but unfortunately I was first diagnosed at 40. So much for that.

Traveltext

Hope this perennial topic kicks onagain! Men have a one in 1000 chance of developing bc in their lifetime and are one percent of new cases. I have genetics against me but I drew the shortest of short straws to get two such opposingly different cancers.

Lilaa

I think , hormonal contraception may trigger BC.. especially if you take it for more than 5-10 years. After asking, even my MO said, that he considered this possibility, too, but there aren't official studies..

Of course there aren't studies. Pharma wouldn't pay for such a study, would cause them losing lots of money if women stop using hormonal contraception

gb2115

There is really no way to know. Our bodies are constantly fighting off cells with DNA mutation all of the time. Cancer develops when that takes hold and can't be fought off. I would love to know what caused mine...I'm young and was BRCA negative, despite a family history. Who knows. I feel like it was something environmental since there are several other women I worked with who all developed breast cancer or other cancer over the years, but narrowing it down and proving anything would be near impossible. Makes you think though. I just keep popping that tamoxifen hoping it'll prevent anything else from taking hold.

Myraknits

I still struggle with the idea that it was totally random. My stats: 58 at DX, 138 lbs, 5'6", 8 yrs past menopause, no family history, 35 yr vegetarian, treadmill 5-6 days a week for many years on and off.

So here what I think it was... I decided 3 yrs previous to my DX to really get in shape. I spent a year dieting and working out and got my weight to 125. I was definitely skinny for the first time ever. Over the next year I got lazy and started eating crap and gained back the weight I'd lost plus a few lbs. we know excess estrogen is a contributing factor so my suspicion is that my weight gain created excess estrogen

I've read enough to understand it's a random mutation, especially considering I had a Her2+ DX but I don't know that I'll ever be convinced that rapid weight gain wasn't a factor as well.

By the way, thanks to lack of exercise, bad eating habits and a daily AI, I'm now up to 150. Frustrating.

BlueKoala

My doctors have all stressed that we can't know what caused my cancer. I haven't done anything to cause it, I am just unlucky.

We know some things that put you at higher risk for breast cancer. That is, things like being overweight, not exercising, taking HRT or birth control, alcohol, dodgy genes, might not cause breast cancer in everyone, but for some people will be a contributing factor to their development of breast cancer. The body has a pretty good process for stopping rogue cells, but those contributing factors can interrupt the process and the rogue cells can get past one or more of the defence mechanisms.

For me, personally, I think the contributing factors were probably:

-exposure to an insecticide every week for a year and a half about ten years before diagnosis

-some dodgy genes that I (or medical science possibly) hasn't found yet (there's a fair bit of cancer floating around my family, but nothing obviously related),

- seven pregnancies (resulting in three live births who were all breastfed for over twelve months) and the subsequent surges of hormones and changes to breast tissue

-being female and having breasts!