Dear duff0015: Tamoxifen is associated with a slightly higher incidence of uterine cancer (regardless of menopausal status) and all women should be monitored for this. There may also be a slightly higher incidence of endometriosis. Endometriosis is a condition whereby the endometrium (or lining of the uterus) grows outside the uterus. Endometriosis does not cause cancer or increase cancer risk per se. However, there is speculation that there may be excess estrogen produced which may impact cancer growth. Endometriosis is most common in premenopausal women age 30-40. It is extremely rare in postmenopausal women but can occur. Lupron is sometimes given to suppress ovarian function, further reducing estrogen in premenopausal women with breast cancer. However, the most popular use of lupron is the treatment of endometriosis. Ovarian function must be monitored when used for suppression because lupron does not always completely suppress ovarian function. If the intention is to use an aromatase inhibitor (which is being trialed in premenopausal ovarian suppressed women), then hormones must be verified to be at menopausal levels. Ultimately, this boils down to a discussion between you and your doctor. You may also wish to consult your gynecologist. You may also benefit from a second opinion from another oncologist – preferably one who specializes in breast cancer. You need to discuss pros and cons of all the options in the context of your situation and a doctor who has specifically reviewed your case will be best equipped for this discussion.
Regarding the issue of lumpectomy and margins vs. mastectomy. A lumpectomy with radiaton and mastectomy have very similar survival rates. A lumpectomy with radiation has a slightly higher local recurrence (recurrence in the breast) rate.
I was almost in the very same position 6.5 years ago. I had a long history of endometriosis, stage 1 ductal carcinoma, very ER+/PR+, lumpectomy and radiation, BRCA negative despite a family history of BC. I was put on Tamoxifen and I was one of the rare few that developed ovarian cysts and my estradiol levels soared to 431. I was experiencing cramping. It was a difficult time because most experts said that couldn't happen. I was then put on monthly Lupron shots and my estradiol levels dropped to less than 10 and the ovarian cysts disappeared. Since I was close to menopausal age, they took me off the Lupron after a year and again my estradiol levels soared. I went back on the Lupron again. The second time I went off the Lupron it appeared by my estradiol levels that I was finally in menopause. However, by that time my endometriosis had expanded and I had a pelviscopy to remove it. I wish now that I would have had a hysterectomy but my gynocologist is conservative and doesn't want to remove anything unless it's cancerous. After 4 years on Tamoxifen, I had a D&C and was switched to an AI (not really available when I was first diagnosed.) After struggling with bone aches for 18 months and 5.5 years of hormonal therapy, I was finally taken off of everything. That in itself is a scary time. This year I had some cramping again and they did the ultrasound, etc and said I had a thickening of the lining again. A biopsy and hormone level test said everything was okay. So they said don't worry, and of course I do. Despite the fact that my oncologist says I'm doing great, the fact is my body betrayed me once and I'm always worried that it will betray me again. However, I suggest that you don't over react at this early stage. Trust your doctors. Keep researching yourself and ask your doctor questions. (I believe England has a lot more experience suppressing ovaries in pre-menopausal women.. do a search on ovarian oblation and breast cancer). Good luck.