Good prognosis of endometrial cancer is related to multiple favorable factors. The cancer generally occurs in menopause because the menstrual cycle involves a monthly renewal of the endometrium and it is therefore protective. When the endometrial cancer is formed, it typically bleeds. This symptom is abnormal in menopause, so the woman refers to the doctor and receives the diagnosis. The cancer is thus diagnosed because it is early symptomatic. Finally, the uterus is a muscle with very thick walls, and usually when diagnosis occurs, the cancer is still confined to the inner part of the organ and the removal of the uterus leads to healing in most menopausal cases.
Screening for endometrial cancer in asymptomatic women is not recommended since real benefits in terms of mortality reduction have not been observed. However, there are groups of women at high risk for endometrial cancer for which screening is recommended (users of tamoxifen (1), Lynch syndrome (2) based on the supposed benefits of early diagnosis, although there are no studies showing a reduction in mortality associated with the disease. In the case of women at high risk, gynaecological transvaginal ultrasound with the measurement of endometrial fissure and possible endometrial sampling have been proposed for screening.
(1) Tamoxifen or tamoxifen citrate is an anticancer drug taken orally, belonging to the family of oestrogen receptor selective modulators. The drug inhibits the effects of oestrogens, the hormones in women, through histone deacetylation, thus nullifying the effects of oestrogen-receptor binding to DNA. This is useful because breast cancer cells often thrive on these hormones. A number of studies show that tamoxifen increases the incidence of uterine cancers due to its pro-oestrogenic effect on the endometrium. The risk of inducing endometrial carcinoma is more pronounced in women who are post-menopausal, obese and in those previously subjected to HRT (hormone replacement therapy). Endometrial carcinoma develops in 0.5-1% of women taking tamoxifen for five years, with a tripled risk compared to controls. In addition, tamoxifen can induce endometrial hyperplasia and polyps. It is currently believed that tamoxifen-induced endometrial cancer does not possess malignancy features exceeding cancers found in the general population
(2) The Lynch syndrome (or hereditary non-polyposis colorectal cancer, or hereditary colorectal carcinomatosis on a non-polyposis basis, Hereditary Non-Polyposis Colon Cancer - HNPCC) is a hereditary form of colon cancer with dominant transmission, which means it has a 50% probability of occurrence in the children of those affected. Unlike familial adenomatous polyposis, the predisposition to the development of the disease is not manifested by the appearance of polyps, but directly with the development of colon cancer, usually around the age of 45. This is the main manifestation of Lynch syndrome I, while that of type II includes other possible malignancies at endometrium, ovary, stomach, urinary tract, bile ducts, in addition to colon cancer. The syndrome is caused by a mutation in one of the DNA MMR genes, MLH1, MSH2, MSH6 and PMS2. Women with Lynch syndrome (LS) have 40-60% risk of developing endometrial cancer, and about 10-15% risk of ovarian cancer. Several screening strategies have been studied but the real effectiveness of endometrial screening remains uncertain. Screening certainly plays a fundamental role in the group of high-risk women who want to avoid prophylactic surgery. The main guidelines recommend screening starting from the age of 30-35 through TV gynaecological ultrasound and endometrial sampling yearly.
Endometrial cancer symptoms are typically bleeding in postmenopausal or perimenopausal women, and recurrent inter-menstrual bleeding in women aged <40 years. However, there are many benign causes of bleeding in post-menopausal patients, endometrial atrophy (50%), endometrial hyperplasia (13%) or endometrial polyps (10%). There is a 10% chance of endometrial cancer and 1% of cervical cancer. Age is the most important independent risk factor associated with blood loss in menopause. Fifty percent of bleeding in women over 70 years is caused by endometrial cancer.
In cases of atypical blood loss, the diagnostic process includes:
Transvaginal gynecological ultrasound (TVS)
Transvaginal scan (TVS) can be associated with sonohysterography followed by histological endometrial sampling. This sampling can be performed in the doctor’s surgery with a very thin catheter (Pipelle de Cornier). This method is non-invasive and well tolerated and its accuracy is 90-98% (ability to correctly identify the stage of the endometrial cancer).
Hysteroscopy with biopsy
Hysteroscopy with biopsy is a viable and equivalent alternative to transvaginal ultrasound with sonohysterography for the diagnosis of endometrial cancer.
TV gynecological ultrasound
TV gynecological ultrasound is a non-invasive test performed in the doctor’s surgery. The ultrasound allows for the evaluation of endometrial thickness and morphology. The normal post-menopausal endometrium is thin, uniform with a thickness of about 1 mm, while in the cases of endometrial cancer it appears thickened and with different morphological characteristics and specifications, in most cases.
The sonohysterography is an ultrasound vaginal probe using contrast medium consisting of sterile saline solution introduced with a syringe into the uterine cavity via a special catheter. It is a test that is performed in the clinic and is well tolerated. Sonohysterography allows discriminating focal endometrial lesions from those spread to the entire endometrial surface and it shows characteristic features in the presence of an endometrial cancer.
- Irregular thickening of the endometrium with heterogeneous and irregular echogenicity at the endo-myometrial junction.
- Difficulty distending the uterine cavity during SCSH.
- The uneven surface of a focal lesion.
Hysteroscopy
Hysteroscopy is a minimally-invasive endoscopic method for both diagnosis and/or treatment of endometrial cancer through which it is possible to visualise the uterine cavity with an instrument called hysteroscope. Surgery can be performed under general anaesthesia or while awake (in selected cases). The first stage consists of the dilatation of the cervical canal with rigid instruments. Then the hysteroscope is introduced, allowing operations to be carried out in the uterus without leaving wounds and/or scars.
Diagnostic hysteroscopy is when the operator only observes the uterine cavity by performing - if necessary - a targeted biopsy of the endometrium. Instead, Operational Hysteroscopyis whenminor surgical interventions are performed during the procedure, such as removal of endometrial polyps or small intracavitary fibroids.