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Home > Understanding Breast Cancer > Breast Cancer Research > Table 56: Menopausal hormone therapy after breast cancer diagnosis and recurrence


Table 56: Menopausal hormone therapy after breast cancer diagnosis and recurrence

This summary table contains detailed information about research studies. Summary tables offer an informative look at the science behind many breast cancer guidelines and recommendations. However, they should be viewed with some caution. In order to read and interpret research tables successfully, it is important to understand some key concepts. Learn how to read a research table.

Introduction: Menopausal hormone therapy (MHT) increases the risk of developing breast cancer (see Table 8) [1]. For this reason, all women, including breast cancer survivors, are advised to avoid long-term use of MHT. MHT is also known as postmenopausal hormone therapy and hormone replacement therapy.

Findings from large randomized controlled trials have shown that for breast cancer survivors, MHT use increases the risk of [2-3]:

Learn about the strengths and weaknesses of different types of studies.  

Study selection criteria: Randomized controlled trials.

Table note: Relative risk above 1 indicates increased risk. Relative risk below 1 indicates decreased risk.


Study Population
(number of participants)


Relative Risk of a Breast Cancer Event 
Among Survivors Who Used Menopausal Hormone
Therapy after Breast Cancer Compared to
Those Who Did Not,
RR (95% CI)

Randomized controlled trials   

Holmberg et al. [2]



Local recurrence, metastasis or
cancer in the opposite breast:
2.2 (1.0-5.1)

Fahlén et al. [3]



Local recurrence:
0.8 (0.3-1.7)

1.0 (0.5-2.3)

Cancer in the opposite breast:
3.3 (1.2-10.9)


1. Writing Group for the Women’s Health Initiative Investigators. Risks and benefits of estrogen plus progestin in healthy postmenopausal women: principal results from the Women's Health Initiative randomized controlled trial. JAMA. 288(3):321-33, 2002.

2. Holmberg L, Iverson OE, Rudenstam CM, et al., for the HABITS Study Group. Increased risk of recurrence after hormone replacement therapy in breast cancer survivors. J Natl Cancer Inst. 100(7):475-82, 2008.

3. Fahlén M, Fornander T, Johansson H, et al. Hormone replacement therapy after breast cancer: 10 year follow up of the Stockholm randomised trial. Eur J Cancer. 49(1):52-9, 2013.

Updated 05/16/14