HOME > Doctor’s Health Advice > Endometrial Cancer

  • Doctor’s Health Advice
  • Yuzo Endo, M.D., Ph.D.
  • Masahito Hitosugi, M.D., Ph.D.
  • John E. Lewis, Ph.D.

Doctor’s Health Advice

Doctor’s Health Advice

Pathologist’s advice on how to combat cancer


Endometrial Cancer

Fatty or dairy food and excessive biliary secretion in the gut

The statistics for uterine cancer rates have remained steady. As I mentioned in the previous essay, uterine cervical cancer rates are decreasing, but endometrial cancer is on the rise. This trend is common among developed nations, and the reasons can be speculated. Nature of both cancers of the uterus is quite different from the light microscopic point of view. The former is mainly squamous cell carcinoma just the same as esophageal cancer or skin cancer in part. The latter is mainly adenocarcinoma just the same as colon or prostate cancer, namely cancer of the exocrine glands. The reasons for decreased cervical cancer are already mentioned the previous chapter. The most important reasons are improvements in genital hygiene and the advancement of sexual education. I have explained previously that virus infection as a major initiator and chronic inflammation as a major promoter in the genital area are the major causes for this kind of cancer. In order to get rid of such virus of the cervical cancer, vaccination against such virus as HPV type 16 to young-adult women has been practical, although it has been anticipated to be at most around 50% in the developed countries.

On the other hand, endometrial cancer is influenced by female hormones, which are significantly impacted by diet, environment and social or cultural settings.In accordance with a number of evidence data, I would like to point out that dairy or fatty meal should be digested absolutely by help of bile from the liver derived from the daily reform of red blood cells, totally around 100 grams. Bile secreted into the gut is useful to be detergent like soap and to help digest fatty food by lipoenzymes from the pancreas or small intestine. During the course of the intestinal tract, bile is often changed into the various substances such as carcinogenic substances like methylcholanthrane in the colon by bad intestinal flora, such as anaerobic clostridium. These substances not only influence directly to the colonic epithelium leading to colon cancer in site, but also are absorbed into the blood and transported to the exocrine glands of our body, such as endometrium and breast in the female, or prostate in the male.

What is endometrial cancer?

In the previous essay, I described the shape and position of the uterus. In this essay I would like to give a brief explanation on its functions from the hormonal perspective.

The whole uterus is made up of thick muscles called smooth muscle, and its inside is covered with soft epithelial tissue, called the endometrium. The fertilized ovum implants in the soft tissue. Two kinds of female hormones from the ovaries, estrogen and progesterone, regulate the condition of the endometrium and smooth muscle. The endometrium changes cyclically every month due to the effects and interactions of these hormones. This cycle is meant to prepare the uterus for conception. When the endometrium doesn’t receive a fertilized ovum, it completes the cycle by shedding the epithelial tissue with hemorrhage, which is known as menstruation. After menstruation, cells of the endometrium are influenced by estrogen to proliferate again. Estrogen promotes normal cell growth, but in some cases it can become a dangerous carcinogenic factor.

About two weeks later, progesterone is secreted from the corpus luteum of the ovaries, which causes the endometrium to become thick and moist for implantation of fertilized ovum. The ovaries respond to the signals given by the hypothalamus and pituitary gland. The hypothalamus is strongly affected by hormone levels in the blood (that had been secreted from the ovaries), and by brain activity, including emotional reactions.

The system to regulate the endometrial cycles is called the feedback system, and consists of the ovaries, hypothalamus and pituitary in the brain. The endometrium is continuously controlled by hormones and the autonomic nervous system, influencing two patterns of cell behavior: cell proliferation (cell growth) and differentiation (maturation and function). Estrogen strongly promotes cell-proliferation while progesterone maintains proliferated cells and controls function of secretions. Therefore, the endometrium is constantly in an environment that encourages cell growth, a condition that is predisposes one to cancer.
Sex hormones are strongly influenced by diet and social or cultural environments. Adolescents are in their reproductive years, and are affected by Western diets that are high in fat, meat, and dairy, in addition to being influenced by sexual precocity closely related to social subcultures. Those scenarios are some of the influential factors for development of endometrial cancer.

Endometrial cancer screening

Early detection of endometrial cancer is generally made through a relatively easy and simple test, that being cytodiagnosis of endometrium and vagina tissue, or Pap smear, which is standard in a gynecological and cytopathological exam. But some women may be uncomfortable with this screening. Whether the cells are benign or malignant, they are diagnosed by a skilled and experienced laboratory personnel and board-certified pathologist using a light microscope. Endometrial cancer is in many cases detected relatively early, because it is accompanied by subjective symptoms such as increased leukorrhea. Besides, progression is relatively slow and is sometimes curable. Therefore, creating opportunities for screening examination is very important.

If a woman suspects such symptoms, she should undergo a screening from a gynecologist. If heteromorphous cells are detected, extensive screening is conducted by taking a tiny portion of the endometrial tissue. This exam is called an endometrial biopsy, which is a type of histopathological test. This test report is regarded as an official document, and a copy should be maintained by the patient for their own records.

Endometrial cancer may sometimes accompany gynecological health problems, such as irregular menstruation or hypermenorrhea. If a woman is having troubles with menopausal symptoms, cytoscopy is recommended as a precautionary measure.

What is endometriosis?

Endometriosis is not cancer, but it is very troublesome and recurrent during menstruation. The rate of endometriosis has been increasing.

In this illness, small or large patches of endometrial tissue may appear and proliferate in other parts of the body. When these tissues grow into the muscular wall of the uterus, it is called adenomyosis, and when it spreads to other areas, it is called endometriosis. These changes are influenced by the cyclical hormone exchanges under the physiological circumstances, such as proliferative or secretory phases, which are the same as the endometrium itself.

Those endometrial tissues respond to hormones according to the menstrual cycle. Therefore menstruation occurs at those displaced patches of endometrial tissue, causing lower abdominal pain, heavy cramps, or anemia. At present there is no specific medicine to eliminate endometriosis.

Hormone replacement therapy

Endometrial cancer and endometriosis have long existed, but the morbidity is rapidly increasing these days in developed nations, including Japan. It may be partly attributed to changes of diets and social or cultural environments, but there is no scientific evidence for it. Some preventive measures should be found and it is clear that female hormones are a key factor for these illnesses.

Hormone replacement therapy (HRT) is becoming prevalent in the US for treating menopausal syndrome. HRT prescriptions have declined significantly since the Women’s Health Initiative study in the mid 90s found that HRT was responsible partly for gynecological cancers or ischemic change of the heart. Menopause is a physiological phenomenon caused by permanent cession of ovarian function, which signifies the end of reproduction functions.

The average life expectancy of the Japanese was once 50 years around 1950, but now it has rapidly increased up to 90 years and at present Japanese people can enjoy their lives far beyond 50 years. Therefore, in such an age it is natural that women are seeking some method to maintain their youth. Hormone replacement therapy may be used to meet those demands.

However, mentioned above, it has been revealed that long-term hormone replacement therapy enhances the risk of endometrial cancer. It may also cause thrombosis and acute ischemic cardiac diseases, including cardiac infarction and angina pectoris. The use of hormone replacement therapy is being re-examined in the US.


Endometrial cancer occurs infrequently, and fortunately its progress is rather slow. However, its incidence in Japan has insidiously risen up, mentioned above. The level of its malignancy varies from benign to malignant. Early detection and early treatment are required; therefore planning to undergo a gynecological exam is important.

A screening exam should be done several times in one’s 50s. If no problems are detected, screening once every five years there on may be adequate. It is also important to select an appropriate hospital and laboratory. The level of gynecological as well as pathological care is important, but at the same time, the medical level of a hospital is determined by the quality of the pathological examination and diagnosis. An ideal hospital should have a pathologist as a permanent member of their staff. These facets of a medical system aren’t visible to the general public, but can be seen by researching a facility’s website. When selecting which hospital to use, it is important to have this information.

This series of essays have continued over the course of two years and is coming close to the end. Only a few essays are remaining. The purpose of this essay was not to describe cancer in detail, but to give advice on each individual’s strategy for cancer prevention and treatment. This is why I decided to discuss some of the more common types of cancer. I think self-care is the ultimate goal of future medicine, in which people become independent, rather than blindly follow their doctors’ instructions, and take care of themselves by improving their own diets and taking supplements appropriately. I would like to promote my idea “Shoku 食=eat followed by I 医=medicine 同源 Dougen=Same Root and Stem” expressed in the Japanese famous proverb-like phrase, “I-Shoku-Dougen 医食同源 ” which has converse means against my idea “To eat adequate food or take supplement like BioBran is fundamentally important. Do not depend upon medicine, as much as possible”, that is my own hearty advice to you!


Yuzo Endo, M.D., Ph.D.

Yuzo Endo, M.D., Ph.D.
Hamamatsu University School of Medicine

1969.9: Graduated from Medical School, University of Tokyo Consultant pathologist in Hamamatsu University, Medical School, and Fujimoto General Hospital. Medical Consultant in conventional and integrative medicine.

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