Reason Why Hormone Therapy Alone Cannot Cure Endometriosis Uncovered

Researchers found great variability in hormone receptor distribution in the lesion of different women with endometriosis as well as in the different lesions of the same woman.

Key Points

Highlights:

• The reason why hormone treatment alone cannot cure endometriosis could be that estrogen and progesterone receptors are not distributed homogeneously in different lesions and between women.

Importance:

• This finding could help shape the future of endometriosis research

Key results:

• There is high variability in the expression of estrogen receptor alpha and progesterone receptor among distinct glands in the same deep infiltrating endometriosis sample.
• There was also heterogeneity among distinct glands.
• There was no typical pattern of hormone receptor distribution in treated or untreated women.
• Finally, there were variations between patients receiving the same hormone treatment.

Limitations of the study:

The study only included 41 women, 18 of whom did not receive hormonal treatment while 23 received three different types of hormone treatment before surgery.

Lay Summary

Researchers in Belgium have shed light on why hormone therapy cannot cure endometriosis on its own in a study published in the scientific journal Gynecological Endocrinology. 

Their findings could shape the direction of future research and may help to find a cure for this complex condition.

Hormone therapy is being used by a large number of women with endometriosis to relieve pain. However, it is known that this is not a cure for the condition and that different women with endometriosis respond differently to hormone therapy. But the exact reason behind this was so far not understood.

Researchers had previously identified mutations in genes that are known to be linked to the formation of cancer in some endometriosis-causing cells but not in others suggesting a heterogeneity among different cells. 

So, in order to better understand the differences among the cells that make up endometrial lesions, Dr. Géraldine Brichant at the University of Liege in Belgium and colleagues looked at the expression of estrogen and progesterone receptors (receptors to which hormones bind to), in endometriosis samples obtained from women with deep infiltrating endometriosis. Some of these women were not treated with hormone therapy, and some were treated with various hormone therapies. Any differences among the epithelial cells could be the reason why patients respond so differently to hormone treatment, the researchers thought. 

They found that the distribution of estrogen receptor alpha and progesterone receptor were not even in these lesions. This unevenness was also seen in the lesions of women who were treated with the same hormone therapy, and no typical pattern of hormone receptor distribution could be identified in women how were not treated or those who were.

The researchers observed a high variability not only among distinct glands in the same sample but also in the same gland, and among different patients receiving the same treatment. These findings indicate that there is considerable variability between epithelial cells activities in deep infiltrating endometriosis lesions even in the same woman.

The researchers concluded that this variability “could explain why endocrine treatments are unable to cure this condition.”

Research Source: https://www.ncbi.nlm.nih.gov/pubmed/29383962