Estrogen replacement effectively controls hot flashes associated with biologic or treatment-associated postmenopausal states in women. The proposed mechanism of action of estrogen replacement therapy is that it ameliorates hot flashes by raising the core body temperaturesweating threshold;[Level of evidence: I] however, many women have relative or absolute contraindications to estrogen replacement. Physicians and breast cancer survivors often think there is an increased risk of breast cancer recurrence or de novo breast malignancy with hormone replacement therapies and defer hormonal management of postmenopausal symptoms. Methodologically strong data evaluating the risk of breast cancer associated with hormone replacement therapy in healthy women have been minimal, despite strong basic science considerations suggesting the possibility of such a risk.
Langerhans cell histiocytosis is a type of cancer that can damage tissue or cause lesions to form in one or more places in the body.
Langerhans cell histiocytosis (LCH) is a rare cancer that begins in LCH cells (a type of dendritic cell which fights infection). Sometimes there are mutations (changes) in LCH cells as they form. These include mutations of the BRAFgene. These changes may make the LCH cells grow and multiply quickly. This causes LCH cells to build up in certain parts of the body,...
In May 2002, the Women's Health Initiative (WHI), a large, randomized, placebo-controlled trial of the risks and benefits of estrogen plus progestin in healthy postmenopausal women, was stopped prematurely at a mean follow-up of 5.2 years (±1.3) because of the detection of a 1.26-fold increased breast cancer risk (95% confidence interval [CI], 1.00-1.59) in women receiving hormone replacement therapy. Tumors among women in the hormone replacement therapy group were slightly larger and more advanced than in the placebo group, with a substantial and statistically significant rise in the percentage of abnormal mammograms at first annual screening; such a rise might hinder breast cancer diagnosis and account for the later stage at diagnosis.[3,4][Level of evidence: I] These results are supported by a population-based case-control study suggesting a 1.7-fold (95% CI, 1.3-2.2) increased risk of breastcancer in women using combined hormone replacement therapy. The risk of invasive lobular carcinoma was increased 2.7-fold (95% CI, 1.7-4.3), the risk of invasive ductal carcinoma was increased 1.5-fold (95% CI, 1.1-2.0), and the risk of estrogen receptor-positive/progesterone receptor-positive breast cancer was increased 2.0-fold (95% CI, 1.5-2.7). Increased risk was highest for invasive lobular tumors and in women who used hormone replacement therapy for longer periods of time. Risk was not increased with unopposed estrogen therapy.