Association between PCOS and Cancers

Emobileclinic Trending Topic: Endometrial Cancer

Endometrial adenocarcinoma is the second most common female malignancy but only 4% of cases occur in women less than 40 years of age. The risk of developing endometrial cancer has been shown to be adversely influenced by a number of factors including obsesity ,long- term use of unopposed oestrogens, nulliparity and infertility. Women with endometrial carcinoma have had fewer births compared with women who have not and with many children . Several studies had demonstrated that infertility per se gives a relative risk.

Hypertension and Type 2 diabetes mellitus have long been linked to endometrial cancer,conditions that are now known also to be associated with PCOS.The true risk of endometrial carcinoma in women with clearly defined PCOS,however,is difficult to ascertain.The degree of risk has not been clearly defined. It is generally accepted that for women with PCOS who experience amenorrhea or oligomenorrhoea, the induction of artificial withdrawal bleeds to prevent endometrial hyperplasia is a prudent management. Indeed it is considered important that women with PCOS shed their endometrium at least every three months. For those with oligo-/amenorrhea who do not wish to use cyclical hormone therapy we recommend an ultrasound scan to measure endometrial thickness and morphology every 6-12 months(depending upon menstraul history) An endometrial thickness greater than 10mm in an amenorrhoeic woman warrants artificial induced bleed,which should be followed by a repeat ultrasound scan and endometrial biopsy if the endometrium has not been shed. Another option is to consider a progestogen secreting intrauterine system, such as the Morena IUS®.

Obesity ,hyperandrogenism, and infertility also occur frequently in PCOS and are features known to be associated with the development on breast cancer. However,studies examining the relationship between PCOS and breast carcinoma have not always identified a significantly increased risk.Another study of the national registry of death over a period of 30 years, observed breast cancer as the leading cause of death among women.

In recent years there has been much debate about risk of ovarian cancer in women with infertility, particularly in relation with the use of drugs to induce superovulation for assisted conception procedures. Inherently the risk of ovarian cancer appears to be increased in women who have multiple ovulations- that is those who are nulliparous (possible because of infertility) with an early menarche and late menopause. Thus it may be inducing multiple ovulations in women with infertility with increase their risk- a notion that is by no means proven.Women with PCOS who are oligo-/anovulatory might therefore be expected to be at low risk of developing ovarian cancer if it is a lifetime number of ovulation rather than pregnancies that is critical.

Ovulation induction to correct anovulation infertility aims to induce unifollicular ovulation and so in theory should raise the risk of a woman with PCOS to that of a normal ovulating women .The polycystic ovary ,however  is notoriously sensitive to stimulation and it is only in recent years with the development of high – resolution transvaginal ultrasonography that the rate of unifollicular ovulation has attained acceptable leveld.

There are a few studies which have addressed the possibility of an association between polycystic ovaries and ovarian cancer.However  the results are conflicting.