Anastrozole and bladder pain

Did your interstitial cystitis cause symptoms like blood showing up in urine, which caused you to think you had a UTI? What sent you to the urologist for a cystoscopy?

So, can you tell me how often and at what time of day you have bladder pain? I have burning pain lower abdomen at night, keeps me awake but rarely have it during the day.

@karenvh, have you talked to your cancer team about this bladder pain? Have they ruled out any infection or other condition that may be causing this pain?

@virginiae
Such an interesting question. I have an estrogen-related issue which may or may not be in the same boat, but may further enlighten the discussion.

Six years ago, as a clearly postmenopausal woman, I began having horrendous UTIs each month (something my mother and older sister also were plagued with). My PCP would give me antibiotics to which I would have strong adverse effects, and sent me to a urologist who said my bladder and kidneys were in great shape. After several months of the UTIs, I went to a gyno-oncologist on another issue and mentioned the UTIs. He said the solution to that was easy and prescribed 10 mcg. vaginal estradiol tablets twice a week (a tiny, tiny amount)... and the UTIs stopped. I haven't had one since. (I had no idea there was a connection, and apparently, neither did my PCP nor the urologist.)

When menopause occurs, estrogen production is reduced, which is the major cause of urogenital atrophy. Atrophy means a wasting away of muscle mass, and urogenital atrophy involves atrophy of the vagina as well as atrophy of the urinary tract. Potential issues include UTIs, stress and urge incontinence, pelvic organ prolapse, vaginal bleeding, etc. There are various lifestyle changes (like reducing caffeine, specific exercises, maintaining a healthy weight, etc.) and medical procedures which can address these. Topical estradiol also is one.

As you likely know, anastrozole is a double-whammy for postmenopausal women... our ovaries are no longer making estrogen, and now the anastrozole is blocking the estrogen from our fat cells and adrenals.

At one time, it was thought that topical vaginal estradiol was contraindicated for HR+ breast cancer patients, as systemic estradiol (HRT) certainly is. More recently, however, studies indicate that postmenopausal breast cancer women who use vaginal estrogen have the same risks (for invasive breast cancer, stroke, blood clots, endometrial cancer, and colorectal cancer) as women who do not use vaginal estrogen.
https://www.breastcancer.org/research-news/vaginal-estrogen-not-linked-to-high-risk
https://www.acog.org/Clinical-Guidance-and-Publications/Committee-Opinions/Committee-on-Gynecologic-Practice/The-Use-of-Vaginal-Estrogen-in-Women-With-a-History-of-Estrogen-Dependent-Breast-Cancer?IsMobileSet=false
https://www.medpagetoday.com/obgyn/breastcancer/56449
The controversy now is whether the tiny amounts of estradiol (10 mcg taken twice a week = 20 mcg.) which breast cancer survivors use for urogenital issues is enough to interfere with the work of anastrozole (1 mg. = 1,000 mcg. taken daily = 7,000 mcg) as to make it substantially less efficacious. The use of estradiol therefore becomes an informed decision as the experts have not come to a conclusion.

Here's hoping that your uro-gyn can assess what's going on with your bladder (due to a prolapsed uterus, for example) and that s/he can provide the relief you need and deserve.

I agree with Trixie, @virginiae. I think a conversation with your doctor about switching AIs immediately is in order. Exemestane might be a good choice