​How quickly can Tamoxifen cause uterine changes?

eviec1

I've been on T for about 2 months. Last week I did a pelvic/TV ultrasound which was intended to establish a baseline that could be monitored for changes. However, this initial ultrasound found thickening (13.5mm) and a suspected polyp (12mm). It also found bilateral simple benign-appearing ovarian cysts. Yikes!

I have never had a pelvic ultrasound before, so I have no idea if these things are new or old. I know that these are all things that T can cause. However, as I said, I've only been on it for 2 months. Could T cause these changes that quickly, or were these issues likely pre-existing? I'll be honest, I'm a bit worried about them (scheduled for hysteroscopy later this month and my anxiety is pretty high).

Any thoughts?

bcincolorado

I was on Tamoxifen for many years with no issues. I did make sure to be checked reguarly but still had no issues at all for me. Does not mean it won't for other people though since every person has different health issues going on as well. I would ask your doctor if it was there before and not caught before perhaps? I assume they also know your cancer diagnosis as well. You can always get a second opinion as well if you are uneasy as well. Best wishes to you.

eviec1

Thanks! At this point, I am nervously awaiting the hysteroscopy and having flashback of waiting for the biopsy results when I was diagnosed with bc...

PamEP

eviec1: Did you have any symptoms of endometrial/uterine irregularity or any side effects from the tamoxifen? And what dosage are you taking? I ask these questions because I just started tamoxifen about a month ago, but at a lower than standard dose. I have noticed some lower abdominal pressure and vaginal discharge that occurred once I started the drug. I have not yet had a pelvic ultrasound.

Tamoxifen is tolerable (for me) as a post-menopausal user but its potential endometrial abnormalities are very worrisome. Research that I have read generally says to stop after 5 years because the endometrial negative SEs occur at a greater rate after that time.

Hope all goes well for you.

eviec1

I am taking the standard 20mg/day dose.

I didn't notice any particular symptoms - I am perimenopausal so my periods have been a little screwy for the past few years, but nothing new since starting T.

The only side effects I've had have been GI-related: I had constipation, gas, and bloating almost immediately after starting. The gas and bloating have gotten better, but the constipation persists.

beach2beach

Hi,

I've been taking T for 4 years. Only recently had a thickened lining which turned out to be a polyp. Had a d/c and removed it and it was benign.

To say whether your thickening could be cause by T is tough. My GYN told me when my routine ultrasound noted the thickening that it could be because I am still peri-menopausal and it could be where I was in my cycle at the time. (I no longer get periods since starting T). Waiting 26-28 days and had a repeat ultrasound, still thickened so he did biopsy. Came back with no changes but polyp. I had the option to keep following at my usual 6mth rate for ultrasound or do a d/c and remove it. I chose it. I was sooooooo nervous but it was an in and out procedure and I was at work next time. Everything came back good. He did tell me he couldn't say whether I would have developed the endometrial polyp even if I wasn't on T..

Let us know how it goes

eviec1

Thanks - it does have me a bit worried. Hoping it's all benign, of course - I am not ready for more problems.

WC3

I was on it for about a year and a half before I developed uterine issues with it. It started to thicken my uterine lining pretty quickly.

Veeder14

Yes I had uterine changes right away on Tamoxifen but didn’t realize it. At 4 months I had my scheduled pelvic ultrasound and my lining was already 17mm up from 2mm prior to beginning Tamoxifen. The tech couldn’t believe it and kept asking me if I was on hrt. Ended up stopping treatment to have a hysterectomy before resuming Tamoxifen

eviec1

Thanks, WC3 and Veeder14 - hearing of your experiences is reassuring that this might just be from the Tamoxifen and hopefully benign.

Jinx27

Im a premenopausal patient and decided to have a vaginal ultrasound as a baseline before starting Tamoxifen. I believe I learned about how it can change the endometrium lining on here.

Since I starting taking it, I have a menstrual cycle, so Im not sure if my answer can help because of my cycle. However I was told by my Gyno that I will have some thickening.

My dose is lower, 10mg every other day, Im building up to 20mg every other day.

eviec1

Thanks, Jinx27, that's good to know! I'm hoping that's all it is. The waiting is awful - as we all already know from our bc diganosis days.

PamEP

I did not get a baseline transvaginal or pelvic US before starting tamoxifen. My MO said I would not need to see an GYN unless I saw blood spotting. That seems more than a little late. I have an appointment to consult with my GP about my tamoxifen concerns and to get a referral to have an US as needed.

We get educated as we go along. I now know more about BC than I ever ever imagined.

eviec1

PamEP, My MO was equally unconcerned about it - she just said, look for abnormal bleeding, but usually that happens in our older patients. She didn't recommend an ultrasound - I made an appointment myself with a gyn to discuss my concerns about T, and she ordered an ultrasound for a baseline and monitoring. My MO never even suggested it! But I guess it's a good thing I did as I clearly have some problems brewing..

PamEP

So what is this, a cost benefit analysis of treatment? Sure, most do not get endometrial/uterine cancer, but a certain percentage do, or get polyps and/or endometrial thickening and other abnormalities. We on the receiving side want to know that everything is right with us. We don't want more drugs and medical interventions to treat side effects. It seems that a baseline and continued monitoring should be standard of care, but it isn't. Good for you to have made that appointment on your own.

Jinx27

PamEP you are absolutely right, I had to push for it, while my Dr. agreed, she stated that wouldn't do one every year, and I told her that wasn't my expectation. I just want to know what changes take place from these meds.

My argument for it was because Im young and my cancer is hereditary (unknown mutation but strong family history) and I need to rule out the risk for ovarian, endometrial cancer too. Sometimes its exhausting having to push soo much, this should be the standard of care.

Had I not learned about that on this website I wouldn't have had it done.

Also you could still get one despite you already having starting Tamoxifen to see any developments.

Eveic1 Im wishing for favorable results for you!

eviec1

Oh my goodness, that hysteroscopy was NO JOKE. The lidocaine went straight to my head, which I didn't expect at all, and I got so dizzy, my ears started ringing, my head started pounding, and I felt like I was going to pass out. It was awful! The gyn said that's an uncommon but possible side effect of the lidocaine - I had no idea and the unexpectedness of it made me panic. The dizziness began to pass about about 5-10 minutes and then I felt a good deal better. I guess there wasn't much actual pain, but very uncomfortable. It was the dizziness that was the worst part. Now waiting on the pathology report.....

PamEP

Eviec1: Wishing you a benign pathology report. Let us know what happens.

After last posting on this thread, I consulted with my PCP. She also said that spotting would be the indicator of endometrial disorder and did not recommend an ultrasound at this time. That is the standard procedure. I am only taking a low dose of tamoxifen, which is supposed to drop the toxicity of the SEs, and am finding the drug more and more tolerable. Apparently some who have problems with tamoxifen are taking Fareston/Toremifene, a similar SERM developed in Finland.

eviec1

Just got this message from my gynecologist:

"Great news- The polyp and the endometrial biopsy are both benign- nothing of concern was noted:)"

PHEW, that is a HUGE relief!

I still don't know whether this was related to Tamoxifen or if these were pre-existing conditions. I have an appointment with my oncologist on the 21st and will talk to her about it - and discuss getting a hysterectomy, because this is too much worry for me.

PamEP

eviec1: That is good news and certainly a huge relief to you! John Link, MO, author of The Breast Cancer Survival Guide, seems to prefer tamoxifen over AI's, and says in the book, "I would guess that I have given around ten thousand women tamoxifen in my career, and I have had no fatality from either of these side effects [venous blood clots and endometrial-uterine cancer]; in fact, close to a thousand women have been cured because of this drug." Reassuring, but not ruling out problems.

Jinx27: Is there a reason you are taking the 10mg every other day? I have tried both splitting the pill and taking 5mg daily and taking the 10mg on alternate days. I wondered about the advisability of splitting the pills, so am tending toward taking the 10mg whole. My MO wants me on 10mg daily, but I am not there (yet). I do find the low dose pretty easy going so far.

inthesage

PamEP I have been fretting about hormone therapy re: bone loss and side effects. I had a zoom appointment with Dr. Link. What a wonderful person. He also said he'd start me on 10mg. tamoxifen. My oncologist here was all geared to begin AI's with Prolia. Once I read about it, I decided against it. I feel in good hands with Dr. Link and it is interesting you are on the low dose. I will ask Dr. Link about the European studies on 5 mg.

PamEP

Inthesage: How lucky you are to consult with Dr. Link. I will be interested in what he has to say about low dose tamoxifen for early stage BC, and 5mg daily vs 10mg alternate days. In all truth, after 5 months of the drug, the SEs even on low dose are beginning to get to me. My energy is lower than my old normal and generally I do not feel up to par. I have muscle aches, cramps at night, bloating, and some trouble with sleep. It would be helpful to talk to someone as specialized and experienced as Dr. Link about benefit vs risk.

Thanks for the update.