Absolute contraindication of hormone replacement therapy is:
**Core Concept**
Hormone replacement therapy (HRT) involves administering hormones to alleviate menopausal symptoms or treat hormone deficiencies. The decision to initiate HRT requires careful consideration of the patient's medical history, particularly factors that may increase the risk of adverse outcomes.
**Why the Correct Answer is Right**
Absolute contraindications are conditions that render HRT inadvisable due to a significant risk of severe adverse effects or no potential benefits. In this context, the correct answer is **Breast cancer**. HRT, particularly estrogen therapy, is known to stimulate the growth of estrogen receptor-positive breast cancer cells, potentially leading to disease progression and worsened outcomes. This is because estrogen can promote cell proliferation, angiogenesis, and metastasis in breast cancer.
**Why Each Wrong Option is Incorrect**
**Option A:** Pregnancy is not an absolute contraindication for HRT, although it may be contraindicated in certain situations, such as a history of thromboembolic events. HRT can be safely used during pregnancy to manage symptoms, but it's usually not the first-line treatment.
**Option B:** Ovarian cancer is not an absolute contraindication for HRT. However, it may be contraindicated in patients with a history of ovarian cancer, as HRT may stimulate the growth of residual cancer cells.
**Option C:** There is no evidence to suggest that thyroid cancer is an absolute contraindication for HRT. In fact, some studies suggest that HRT may have a protective effect against thyroid cancer.
**Clinical Pearl / High-Yield Fact**
When considering HRT, it's essential to weigh the benefits against the potential risks, particularly in patients with a history of breast cancer or other hormone-sensitive cancers. Always assess the patient's individual risk profile and monitor for adverse effects closely.
**Correct Answer: C. Thyroid cancer**