A 55-year-old woman is diagnosed with breast cancer and undergoes breast-sparing mastectomy. The tumor margin did not show any invasion, and sentinel axillary lymph node biopsy was negative for nodal metastasis. The tumor was estrogen receptor and progesterone receptor positive but HER-2 negative. After discussion of management options, the patient is started on tamoxifen. While on this medication, she experiences hot flashes that come and go in waves and affect her sleep significantly. Which of the following conditions is the patient also likely to experience as a result of this therapy?

Question

A 55-year-old woman is diagnosed with breast cancer and undergoes breast-sparing mastectomy.  The tumor margin did not show any invasion, and sentinel axillary lymph node biopsy was negative for nodal metastasis.  The tumor was estrogen receptor and progesterone receptor positive but HER-2 negative.  After discussion of management options, the patient is started on tamoxifen.  While on this medication, she experiences hot flashes that come and go in waves and affect her sleep significantly.  Which of the following conditions is the patient also likely to experience as a result of this therapy?

Quizplus · Accepted Answer

11ec160b_3bab_0e7e_9249_4b3dd43dc9cf_MD0001_00 Tamoxifen and raloxifene are selective estrogen receptor modulators (SERMs). They interact with the estrogen receptor and have agonist or antagonist activity depending on the tissue. In breast tissue, tamoxifen has an anti-estrogenic effect, and it is used for adjuvant treatment of estrogen receptor-positive breast cancer. Tamoxifen reduces the risk of recurrent cancer as well as estrogen-dependent benign breast lesions (eg, fibroadenoma, cystic changes) (Choice D). In endometrial tissue, however, tamoxifen has a stimulatory effect and can lead to development of endometrial hyperplasia and endometrial cancer. This risk is not seen with raloxifene. (Choice A) Tamoxifen and raloxifene act as partial estrogen receptor agonists in bone and can cause an increase in bone mineral density after menopause. (Choices B and E) Tamoxifen has a favorable effect on serum lipids, with a decrease in total and LDL cholesterol and no significant change in HDL. Serum triglycerides may increase in some patients. Educational objective: Selective estrogen receptor modulators (eg, tamoxifen, raloxifene) are competitive inhibitors of estrogen binding to estrogen receptors. They can have agonist or antagonist effects depending on the specific tissue. Tamoxifen has an estrogenic effect on the uterus and can cause endometrial hyperplasia and cancer. __________ References: Tamoxifen treatment for breast cancer and risk of endometrial cancer: a case-control study. (http://www.ncbi.nlm.nih.gov/pubmed/15741574)

A 55-Year-Old Woman Is Diagnosed with Breast Cancer and Undergoes