Women with hormone‑sensitive breast cancer often get hot flashes from their anti‑estrogen treatments. Traditional hormone‑replacement pills can’t be used because they may fuel the cancer. New research suggests that the brain's kisspeptin system may help cause these flashes, and drugs that block a related receptor (NK3) have shown early promise in reducing them in non‑cancer patients, but more studies are needed.

Breast cancer is the most frequently diagnosed cancer in women and the first cause of cancer death in France. Among the different subtypes of breast cancer, the predominant form is characterized by positive hormone receptors (more than 70% of breast cancers). Hormone therapy thus plays a key role in the strategy of management of these cancers both in adjuvant and metastatic situations. The two types of adjuvant hormone therapy used are selective estrogen receptor modulators and aromatase inhibitors. Fulvestrant, an anti-estrogen, is used alone or in combination with other molecules in metastatic situations. Hot flashes are one of the symptoms most frequently reported by patients under hormone therapy. Hormone replacement therapy, which is currently the most effective treatment for hot flashes, is contraindicated in patients with a personal history of breast cancer. Various therapeutic classes of drugs have been tested in this indication but without real efficacy in the various studies carried out to date, and moreover associated with non-negligible side effects. The recent discovery of the implication of the kisspeptin system located at the hypothalamic level in the mechanism of genesis of hot flashes opens the way to possible new symptomatic treatments for hot flashes. Neurokinin 3 receptor antagonists have shown encouraging preliminary results in postmenopausal cancer-free patients and could be considered in patients in hormonal therapy for breast cancer. Broader additional studies are needed to confirm these initial results.