Link Between Endometriosis and Ovarian Cancer

Endometriosis is associated with certain types of ovarian cancers, according to a recent study.

Endometriosis is a condition where the lining of the uterus is found at sites outside the uterus, including the ovaries and the pelvis. It could result in painful periods, pelvic inflammation and even infertility.

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Endometriosis is a chronic painful disorder with endometrial tissue found at abnormal sites such as ovary and tubes. It causes pelvic pain and fertility issues.

Endometriosis has been associated with a particular type of ovarian cancer called invasive epithelial ovarian cancer. This type of cancer can be of 5 types depending on the biopsy picture - clear-cell, endometrioid, mucinous, high-grade serous, and low-grade serous.

A study was carried out to assess which specific type of epithelial ovarian cancer is associated with endometriosis. For the study, results of 13 previously published case-control studies on this topic were analyzed. These studies were conducted in Australia, United States and Europe.

The data was obtained from a total of 23, 144 women, of which 7911women had invasive ovarian cancer and 1907 women had borderline ovarian cancer. Other information regarding age, ethnic origin, parity, breastfeeding, duration of oral contraceptive use, family history of ovarian cancer, weight, height, and history of tubal ligation was also recorded.

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In the study, 9.3% women with invasive epithelial ovarian cancer and 8.8% women with borderline ovarian cancer had been diagnosed with endometriosis.

When the invasive ovarian cancer patients with endometriosis were classified according to types of cancer, it was found that 20.2% women had clear-cell cancer, 13.9% had endometrioid cancer, 6.0% had mucinous cancer, 7.1% had high-grade serous cancer, and 9.2% had low-grade serous type of cancer.

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In women with borderline ovarian cancer and endometriosis, 9% women had borderline serous and 8.5% had borderline mucinous cancer.

Conditions like breastfeeding, weight, height, body-mass index, tubal ligation, and family history of ovarian cancer did not influence the risk of ovarian cancer in patients with endometriosis.

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The study found that endometriosis was not associated with borderline ovarian cancer. It was however associated with invasive epithelial ovarian cancer, especially invasive low-grade serous, endometrioid, and clear-cell types.

A clearer understanding of the topic would help to screen women with endometriosis regularly for early detection of specific types of ovarian cancer.

Reference:

1. Association between endometriosis and risk of histological subtypes of ovarian cancer: a pooled analysis of case—control studies; Dr.Celeste Leigh Pearce et al; The Lancet Oncology 2012. DOI:10.1016/S1470-2045(11)70404-1

Source-Medindia