Hormonal Replacement after Breast Cancer: What’s New?
Hormone replacement therapy (HRT) in menopause for women with a history of breast cancer remains one of the most complex and debated topics in gynecological endocrinology. For a long time, an extremely conservative approach prevailed, focused on the fear of recurrence. However, new evidence and guidelines now allow for a more personalized and balanced evaluation.
Hormone replacement therapy (HRT) in menopause for women with a history of breast cancer remains one of the most complex and discussed topics in gynecological endocrinology. For a long time, an extremely conservative approach prevailed, focused on the fear of recurrence. However, new evidence and guidelines now allow for a more personalized and balanced evaluation.
Understanding the complexity: the role of tumor biology
Not all breast cancers respond the same way to hormones. Therefore, it is essential to understand the histology and molecular profile of the tumor:
| Tumor subtype | Hormonal receptors | Implication for HRT |
| Invasive ductal carcinoma ER+ | ER+/PR+ | Contraindicates systemic HRT |
| Pure HER2+ carcinoma | No hormonal expression | Case-by-case evaluation |
| Triple-negative (ER-, PR-, HER2-) | Absence of receptors | Greater openness to discuss HRT |
| Curable in situ carcinoma (DCIS/LCIS) | Dependent on subtype | May be considered |
What do the main evidences say?
- The CGHFBC meta-analysis published in The Lancet (2019) noted an increased risk of recurrence with the continuous use of combined HRT in women with ER+ cancer.
- Isolated estrogen demonstrated much lower risk, primarily in women who have undergone hysterectomy.
- An integrative review published in 2025 (Acervo Saúde) showed that the duration and type of hormone used directly influence this risk.
New guidelines: more individualization
The NICE (2024) and BMS (2024) guidelines propose a more flexible approach:
- Systemic HRT remains contraindicated in active or recent ER+ breast cancers.
- It may be discussed in cases of triple-negative or HER2+ cancer, cured many years ago, always with the approval of the oncologist and specialized team.
Vaginal estrogen: a safe option?
- According to NICE and BMS, low-dose vaginal estrogen does not increase the risk of recurrence in women with ER+ breast cancer.
- A study presented at ASCO 2025 showed that women over 65 who used vaginal cream showed reduced mortality.
- They may be indicated for urogenital symptoms such as vaginal dryness, dyspareunia, and recurrent urinary infections, always with multidisciplinary follow-up.
Practical tips for clinical practice
- Active or recent ER+ breast cancer: formal contraindication for systemic HRT.
- Triple-negative, pure HER2+, or cured DCIS: may allow individualized evaluation.
- Local low-dose vaginal estrogen: safe even in ER+, with oncologist approval.
- The therapeutic decision must be shared and multidisciplinary, considering risks, benefits, and the patient’s quality of life.
References:
- NICE. Menopause: identification and management (NG23). 2024.
- British Menopause Society (BMS). Consensus Statement, 2024.
- The Lancet. Type and timing of menopausal hormone therapy and breast cancer risk. 2019.
- Acervo Saúde. Hormonal therapy in menopause and breast cancer: integrative review. 2025.
- Reuters Health. Older breast cancer patients using estrogen cream live longer. 2025.
- The Times. Menopausal cancer survivors offered HRT under new guidance. 2025.
Article written by Dr. Francisco Tostes, Scientific Director at Renewal.
