DCIS and Tamoxifen

DaBahm

I’m just wondering as I go through the threads how many people were offered or opted to take hormone therapy after DCISdx. I treated my multicentric DCIS with a mastectomy and was recommended Tamoxifen. I am trying to find a way to take it that minimizes side effects but am also wondering how much fight is it worth. GP says not much, MO wants me on. Looking for others thoughts and reasons.

Ingerp

DaBahm--I'd ask your MO how much Tamoxifen will reduce your probability of recurrence and base my decision on that.

MBPooch

I was never offered hormone therapy after my BMX for DCIS and Pagets. Did you have close margins?

DorothyB

How much does your doctor want you to take?

https://www.medscape.com/viewarticle/906170

I had both IDC and DCIS so the above article doesn't apply to me. However, I did opt to take 10 mg, not the 20 mg prescribed by the MO. I was up to 12.5 mg and going down to 10 mg has reduced my side effects of "being a zombie", leg cramps (still get them, but less) and hot flashes (are now warm flashes).

DaBahm

Ingerp and DorothyB: MO wants me on 20mg and says there’s maybe a 6% chance of recurrence.

MBPooch: Margins were not close on the mastectomy.

It seems like overkill a bit but also not if that makes sense

Beesie

After a MX for DCIS, unless the margins are close, the recurrence risk is in the range of 1% - 2%. There have been lots of studies over the years that have confirmed this.

Given that Tamox reduces recurrence risk by 50%, this means that the absolute benefit is at most 1%. This is why treatment guidelines generally do not recommend Tamox. after a MX for DCIS.

For those who have a UMX and not a BMX, the greater (in terms of benefit) reason to take Tamoxifen is to protect the remaining breast. Once diagnosed one time, we are all higher risk to be diagnosed again, not with a recurrence but with a new primary breast cancer. Tamoxifen can significantly reduce this risk.

The issue to consider however is that this higher new primary risk stays with us for our entire lives, and like all women, our risk to develop breast cancer is greatest when we are in our 60s and 70s. So if you want to take meds to reduce this risk, depending on your age now and how long you want to stay on endocrine therapy (whether Tamoxifen or an AI or Tamox followed by an AI), it may make sense to take it now or it may be a better option to delay for a few years. 5 years of Tamox will reduce your new primary risk for more than 5 years, but for someone who is 49 at time of diagnosis, as I was, it would not provide much risk reduction 15 or 20 years out. This is why in my case (DCIS-Mi, UMX), my MO discussed Tamox with me but recommended against it at that time.

Lots to consider.

DaBahm

Ahhh, finally home and not trying to type on my phone. Thank you guys for responding! And yes Beesie, I forget that I still have to protect the other side. DorothyB, I had asked for 10mg so I could split the doses and am thinking I may dial back a bit and try to get the side effects under control. I’m going to try to stick with it:

DaBahm

To minimize SE’s I started taking all 20mg of tamoxifenat night with an ambien and moved other medications to the morning. It seems to work well enough that I feel like myself again in case anyone ends up in the same spot.