Uterine Cancer
Uterine Cancer: A Global View
Nitisha Sinha, Dr. Lopamudra Das Roy
Published 2021
@BreastCancerHub, All Rights Reserved
Abstract
Background: Uterine Cancer is one of the most common types of gynecologic cancers (cancer that occurs in the female reproductive system). As derived from its name, the cancer is developed in the uterus, usually forming at the lining of the uterus, also called the endometrium.
Aim: Directed to break down the causes and the effect of social, medical, and regional issues contributing to the known data on Uterine Cancer, this paper aims to sum up and explore uterine cancer.
Methods: The information and content were derived from recent credible sources gathered through PubMed, Mayo Clinic, The American Cancer Society, and other reliable cancer institutes.
Discussions: Uterine cancer is more common in white women than black women, but has higher rates of aggressive cancer development and deaths in black women. It is also generally detected early in developed countries, which allows for a more favorable prognosis. However, in developed and undeveloped countries, there are not enough resources or awareness to even record the correct data.
Conclusion: In developed countries, uterine cancer has a more favorable outcome, as there are more options and resources to combat and help fight the disease, whereas it is the opposite for developing and undeveloped countries. This paper shows that there is a need for more research and attention to uterine cancer that must be directed to developing countries, and further awareness should be spread.
About Uterine Cancer
Uterine cancer is formed when malignant cells multiply and grow into a tumor and spread to other tissues of the body.¹ The terms uterine cancer and endometrial cancer are often interchanged but they are not the same thing. Uterine cancer is the general term that encompasses cancers that take place in the uterus.² There are two branches of uterine cancer-- endometrial cancer and uterine sarcoma.² Uterine sarcoma is a rare form of uterine cancer. It develops in the uterus’ muscle wall, called the myometrium. Endometrial cancer is much more common than uterine sarcoma is-- in fact, endometrial cancer is one of the most common gynecological cancers in developed countries. More than 90% of uterine cancers occur in the endometrium.³ Due to endometrial cancer’s greater frequency than uterine sarcoma, the terms uterine cancer and endometrial cancer often get mistaken as being the same.⁴
Causes and Risk Factors:
It is important to be aware of the risk factors in order to minimize the risk of uterine cancer. Patients diagnosed with uterine cancer are usually women who are over 50, commonly being seen to have high levels of excess estrogen and also tend to have a high body mass index (BMI).⁵ More factors that can contribute to a higher risk of uterine cancer are:
Older age: increases the chance of developing uterine cancer, as this cancer usually occurs after menopause.¹
Longer Menustrual Cycle: Beginning your menstrual cycle before the age of 12 or experiencing menopause later in life. Irregular patterns of ovulation can cause an increased risk of this cancer.⁶
Lynch syndrome: Inherited colon cancer syndrome, like Lynch syndrome, is a syndrome that increases the risk for many different cancers, including uterine cancer.⁶
Obesity/High BMI: Extra body fat increases the levels of estrogen in a woman’s body.⁶ Not only is this hormone known to increase the risk of uterine cancer, but also other gynecological cancers and breast cancer as well. So, maintaining a healthy weight, eating healthy, and increasing exercise is an important prevention method that will also help to keep people at less risk of other diseases and medical issues as well.
Hormone Therapy: Talk to your doctor about the issues relating to taking hormone therapy after menopause, as uterine cancer is triggered due to the imbalance of hormones. Another possibility to reduce the risk is to take a combination of estrogen and progestin (the synthetic form of progesterone) in order to maintain more balance. This should be discussed with a doctor first, as there are various other risks caused by taking hormone therapy.⁶
Detecting, Diagnosing, and Treating:
Uterine cancer, especially if it is of the endometrium, is generally easy to detect due to its abnormal signs such as profuse vaginal bleeding.⁷ If you experience any of these signs and symptoms of uterine cancer, you should discuss them with your doctor.
Vaginal Bleeding happening after menopause. The bleeding that occurs does not have to be an abnormal amount, just a little can be the sign of impending uterine cancer, and thus should prompt an evaluation.⁷
Pelvic pressure, urinary symptoms, vaginal discharge, and abdominal pain.⁷
Diabetes or High Blood Pressure.⁷
Having a prior history of infertility or irregular periods.⁷
Have a family history of endometrial, breast, or colorectal cancer.⁷
For women who are premenopausal: signs of uterine cancer include irregular menstrual bleeding, spotting, watery or blood-tinged vaginal discharge as well as bleeding between menstrual periods.⁸ ⁹
To diagnose uterine cancer, a physical and pelvic exam is performed, as well as some more tests to confirm the diagnosis.
Tests that are used to diagnose uterine cancer:
CA-125 assay: This is a blood draw that is used to measure the amount of CA-125 in your body. CA-125 is a protein that can be a sign of cancer if it is higher than normal. ⁶
CT scans, MRI scans, Transvaginal Ultrasound: These take clear pictures of the inside of the body in order to see if there are any abnormalities. ⁶
Endometrial biopsy: This is used to remove a small section of the endometrium for testing via a thin, flexible tube that goes through the cervix into the uterus. ⁶
Treatment
Uterine cancer is commonly treated through surgery, specifically a hysterectomy, removing the uterus and other surrounding organs that could be affected by the cancer cells.⁶
Genetics
Studies have shown that uterine cancer has the highest frequency of the overexpression of the gamma actin gene called ACTG1. Women who had ACTG1 gains were recorded to have poor prognoses.¹⁰ This gene suppresses the body’s immune system and represses its ability to reject the cancerous tumor.¹¹ All forms of uterine cancer, including both endometrial cancer and uterine sarcoma as well as their subdivisions, have been detected to have 5~20% of the ACTG1 gene overexpression.¹⁰
Global Scenario: Analyzing the Statistics of Uterine Cancer
In 2021, it is estimated that a total of 66,570 women in the United States will be diagnosed with uterine cancer.¹² According to the World Health Organization (WHO), there was an estimated number of 417,367 new cases of uterine cancer in 2020 at a global scale, with a corresponding death count of 97,370. It also accounts to have an estimated number of 1,415,213 prevalent cases (span of 5 years) in 2020 worldwide and is the 5th most prevalent type of cancer found in women after cervical cancer (1,495,211 people), with breast cancer (7,790,717 people) at the top. Out of all women’s cancer prevalence in 2020, uterine cancer takes about 5.5% of the total number.¹³ ¹⁴ ¹⁵
Continent-wise, the largest number of cases and deaths of uterine cancer reside in Asia. This is most likely due to the higher population density and accounting for all of Asia as the biggest continent, thus naturally, more cases would be present in this continent. The crude rate of new cases is more accurate representation of uterine cancer incidences affecting the populations in different regions of the world. North America and Europe seem to have the highest crude rates of new cases (approximately 33-36%) and the highest mortality.¹³ Africa seems to have very low statistics which could be attributed to unreliable sampling (underreported/undiagnosed) of data from the African region.
Ethnicity
Uterine Cancer has one of the largest racial disparities among all cancer types.¹ Extensive research has shown that uterine cancer rates are significantly higher for white women than they are for Black women.³ However, despite having lower rates of developing uterine cancer, Black women are more likely to be diagnosed with more aggressive types, thus resulting in lower survival rates as compared to White women.¹⁶ The data from table A shows that Europe and North America having the highest crude rates of new cases, exceeding the other regions by a wide margin. This supports the research data that this disease is more prevalent among white women.¹⁷ Hispanic women, similar to Black women, also have a greater chance of developing more aggressive tumors.¹² In contrast, it has been found that Asian women tend to have higher survival rates.¹⁶
Human Development Index (HDI) is a statistic composite index measuring the life expectancy, education, and per capita income of a country.²⁰ The developed countries are expected to have higher HDI in comparison to the developing or undeveloped countries.
In order to get a correlation between the number of uterine cancer deaths and HDI, the mortality rate needs to be evaluated. The mortality rate is the ratio of the number of deaths occurring per 100 new cases of uterine cancer. The data presented above shows a visible trend of lower mortality rate in higher HDI countries which can be attributed to advanced medical facilities available in those developed countries, enabling early detection and treatment of uterine cancer cases. In contrast, developing countries that have a lower HDI are not wealthy enough to provide these services to their citizens, which results in late detection and thus a higher mortality rate.
Undeveloped countries, which have an even lower HDI, may not even be able to record the accurate number of cases of uterine cancer as there are fewer resources or awareness on the disease. This could thus account for the questionable mortality rate shown in the table for the Low HDI population, as the number of new cases and deaths are most probably heavily skewed.
Results
While uterine cancer is a disease that is relatively easy to detect and allows for early diagnosis and positive outcomes, many women do not know when to seek care and recognize the symptoms, instead pushing them off to be minor, more benign conditions.²¹ As detection is delayed, the cancer becomes more severe; thus it is important to raise more awareness on uterine cancer and help communities understand the importance of being aware of the risks. The data analyzed and brought together in this paper shows that developing and developed countries are lacking data recording that is throwing off the numbers of the global statistics of uterine cancer. Educating and spreading information about uterine cancer is a necessity in both developed and developing countries.
References
https://www.mayoclinic.org/diseases-conditions/endometrial-cancer/symptoms-causes/syc-20352461
https://www.cancer.org/content/dam/CRC/PDF/Public/8858.00.pdf
https://www.cancer.net/cancer-types/uterine-cancer/statistics
Boeckstaens, S. et al. (2020) Signs and symptoms associated with uterine cancer in pre- and postmenopausal women. Heliyon. E05372.
Colombo, N. et al. (2016) ESMO-ESGO-ESTRO Consensus Conference on Endometrial Cancer. Int J Mol Sci. 26(1): 2–30.
https://my.clevelandclinic.org/health/diseases/16409-uterine-cancer
https://www.webmd.com/cancer/understanding-endometrial-cancer-basics
Soliman P.T. et al. Risk factors for young premenopausal women with endometrial cancer. Obstet. Gynecol. 2005;105:575–580.
R, Camden. et al. (2020) Genomic Amplification and Functional Dependency of the Gamma Actin Gene ACTG1 in Uterine Cancer. Int J Mol Sci. 21(22): 8690.
https://www.cancer.gov/about-cancer/treatment/types/immunotherapy
https://www.cancercenter.com/cancer-types/uterine-cancer/about
Clarke, M. A. et al. (2019) Hysterectomy-Corrected Uterine Corpus Cancer Incidence Trends and Differences in Relative Survival Reveal Racial Disparities and Rising Rates of Nonendometrioid Cancers. J Clin Oncol. 37(22): 1895–1908.
Novinson, D. et al. (2020) Increasing Awareness of Uterine Cancer Risks and Symptoms by Using Campaign Materials from Inside Knowledge: Get the Facts About Gynecologic Cancer. J Cancer Educ. 34(6): 1190–1197
Novinson D. et al. (2019) Increasing Awareness of Uterine Cancer Risks and Symptoms by Using Campaign Materials from Inside Knowledge: Get the Facts About Gynecologic Cancer. J Cancer Educ. 34(6): 1190–1197
