From the Guidelines
Hormone replacement therapy (HRT) is generally contraindicated in patients with ductal carcinoma in situ (DCIS) of the breast. According to the NCCN clinical practice guidelines in oncology 1, the focus is on risk reduction therapy for ipsilateral and contralateral breast, with consideration of endocrine therapy for patients with ER-positive DCIS. However, this does not imply the use of HRT, which has a different context and purpose. Women with a history of DCIS should avoid systemic HRT due to the increased risk of breast cancer recurrence or progression. DCIS is considered a precursor to invasive breast cancer, and since many forms of breast cancer are hormone-sensitive, introducing additional estrogen and/or progesterone through HRT could potentially stimulate growth of residual cancer cells.
For menopausal symptom management in these patients, non-hormonal alternatives should be considered first, such as:
- Selective serotonin reuptake inhibitors (SSRIs) like paroxetine (7.5-25mg daily) or venlafaxine (37.5-150mg daily) for hot flashes
- Vaginal moisturizers for vaginal dryness
- Lifestyle modifications including regular exercise and maintaining healthy weight. In rare cases where severe menopausal symptoms significantly impact quality of life and do not respond to alternatives, a very low-dose, short-term HRT might be considered after thorough discussion of risks with an oncologist and gynecologist, particularly if the original DCIS was estrogen receptor-negative. The guidelines 1 emphasize the importance of counseling regarding risk reduction, which should include discussions about the potential risks of HRT in patients with a history of DCIS.
From the Research
Hormone Replacement Therapy in Breast DCIS Patients
- The use of hormone replacement therapy (HRT) in patients with ductal carcinoma in situ (DCIS) of the breast is a topic of ongoing debate, with some studies suggesting that it may be contraindicated due to the potential risk of breast cancer recurrence 2.
- However, other studies have found that the evidence on the impact of HRT on breast cancer recurrence and survival is controversial, and that HRT may be effective in managing menopausal symptoms in breast cancer survivors without significantly increasing the risk of recurrence 3, 4.
- A review of the literature on HRT in cancer survivors found that the oncologic risk of HRT is extremely difficult to assess, and that the decision to prescribe HRT should be made on a case-by-case basis, taking into account the individual patient's risk factors and medical history 2.
- Some studies have suggested that HRT may be relatively contraindicated in patients with hormone-sensitive breast cancer, but that the data on safety for patients with DCIS is inconclusive 5, 6.
- Overall, the current evidence suggests that HRT should not be automatically contraindicated in patients with breast DCIS, but that a shared-decision-making approach should be used to weigh the potential benefits and risks of HRT in each individual case 3, 4.
Key Considerations
- The potential benefits of HRT in managing menopausal symptoms and improving quality of life in breast cancer survivors must be balanced against the potential risks of breast cancer recurrence 3, 4.
- The decision to prescribe HRT should be made on a case-by-case basis, taking into account the individual patient's risk factors and medical history 2.
- Further research is needed to fully understand the impact of HRT on breast cancer recurrence and survival, and to inform evidence-based decision-making in this area 3, 4, 6.