1. What is the prostate gland? The prostate is a male accessory gland, a small gland shaped like a chestnut, located below the bladder and in front of the rectum, through which the urethra passes. The prostate gland is lined with many small glandular ducts and the surrounding stroma. The physiological function of these small ducts is to produce prostatic fluid, which is mixed with sperm and seminal fluid to form semen during ejaculation. The prostate fluid can nourish the sperm and keep the semen in a liquid state. 2.What is prostate cancer? Prostate cancer is a malignant tumor that usually occurs in the epithelial cells inside the prostate ducts. If the epithelial cells in the ducts grow out of control, they will grow into malignant tumor cells, thus forming prostate cancer. Like other cancers, prostate cancer can locally invade surrounding tissues and metastasize to distant areas, forming metastases that damage other tissues and organs at a distance. Due to its high incidence, prostate cancer has become a serious health problem worldwide. Worldwide, prostate cancer is located in the 3rd place of male tumor incidence and 6th place of malignant tumor mortality. In the United States, prostate cancer is the most common malignancy in men, with more than 230,000 men developing prostate cancer each year and more than 29,000 patients dying from it each year. In China, the incidence of prostate cancer has been increasing year by year with the aging of the society, the introduction of western diet, the level of diagnosis and the increasing awareness of prostate cancer as a disease. 2009 incidence rates of prostate cancer in Guangzhou, Beijing and Shanghai were 17.57 per 100,000, 19.30 per 100,000 and 32.23 per 100,000 respectively. 2012 China Cancer Annual Report showed that Prostate cancer is located in the sixth place of incidence and ninth place of malignant tumor deaths in Chinese men. As with many other tumors, the pathogenesis of prostate cancer is unknown. Genetic and environmental factors play an important role in the occurrence and development of prostate cancer. Prostate cancer is more common in older men, African Americans and those with a family history of prostate cancer. Overall, prostate cancer is relatively less malignant. Most prostate cancers grow slowly, are small and lack clinical manifestations in their early stages, and rapidly growing prostate cancers are relatively rare. However, in the case of high-risk prostate cancer that grows rapidly, the disease can progress very quickly. Patients with limited prostate cancer have a relatively high 5-year survival rate with appropriate treatment. In the United States, the 5-year cancer-specific survival rate for prostate cancer is 99%. In China, the 5-year cancer-specific survival rate for prostate cancer is only 55%, which is a huge difference. The difference between China and Europe and the United States in the treatment of prostate cancer is due to the difference in the level of medical care on the one hand, and the lack of awareness of the disease among our society and high-risk groups on the other, which has deprived some patients of the opportunity for early diagnosis and treatment. If diagnosed early, prostate cancer has a chance to be cured. 3.What are the causes and risk factors for prostate cancer? The exact cause of prostate cancer is not known. Medical scientists are working hard on related research to try to find answers as soon as possible. Current theories suggest that many factors may increase a man’s risk of developing prostate cancer. These possible factors include: Age: Prostate cancer occurs primarily in older men, with the average age of newly diagnosed prostate cancer being 72 years old and rare in men under the age of 40. As men get older, their risk of prostate cancer increases. Smoking: The risk of prostate cancer is doubled if there is a history of smoking. Regional distribution: There are significant differences in prostate cancer incidence and mortality rates in different regions of the world. In Asian regions such as China, the incidence of prostate cancer is low (but has increased rapidly in recent years), and in Central America and Western Africa, the incidence is intermediate. The incidence of prostate cancer is higher in North America (e.g., the United States) and Northern Europe (Scandinavia). The higher incidence of prostate cancer in North America and Northern Europe may be attributed to factors such as screening for prostate cancer, genetic susceptibility, dietary habits, and the environment. Race: Incidence rates by race are highest for blacks, followed by whites and yellows, in that order. Black Americans are the highest risk group, with an incidence rate of over 200/100,000 for black men. Black Americans tend to present more as high risk for prostate cancer and have a worse overall prognosis than Asians. Family history: Men with a family history of prostate cancer have an increased risk of developing prostate cancer. The more first-degree relatives who have prostate cancer, the higher their own risk of developing prostate cancer. Men with a family history of prostate cancer are 2 to 10 times more likely to develop prostate cancer than those without a family history of prostate cancer. Diet: There is evidence that Western lifestyles are associated with an elevated risk of prostate cancer and increased prostate cancer mortality. However, the mechanisms linking these particular lifestyles to the development of prostate cancer are not known. Excessive intake of calories, fat and sugar, reduced intake of fruits and vegetables and reduced exercise may increase the risk of prostate cancer, but this relationship is also not entirely clear. Obesity is associated with a higher risk of death from prostate cancer. Therefore, the simplest advice for avoiding death from prostate cancer is to avoid excessive obesity. Limited research evidence has found regional differences in prostate cancer incidence, potentially related to soy protein intake. Asian countries such as China, Japan and South Korea, for example, have prostate cancer incidence and mortality rates that are less than half those in North America, and the intake of soy protein in the form of tofu, soy milk and miso is 90 times higher in these countries than in the United States. In studies in more than 40 countries, researchers found that soy was the most protective dietary factor. This protective effect may be related to two components of soy, lignans and soy glucosinolates, which may act as a weak estrogen. And estrogen can inhibit the growth of prostate cancer. Some other experts suggest that differences in prostate cancer incidence worldwide may also be explained by the high intake of green tea in Asian populations. However, deciding which factors can cause prostate cancer from a complex dietary structure is not easy, and so far there is no clear answer. The intake of certain dietary factors, such as lycopene and cod liver oil, may reduce the risk of prostate cancer. Lycopene is nature’s most powerful antioxidant, and it may protect cells to reduce the risk of cancer. Studies have shown that high intake of lycopene can reduce the risk of prostate cancer. Researchers found that men who consumed two or more servings of ketchup per week had a 36 percent lower risk of prostate cancer compared to men who did not consume ketchup. However, not all studies support this conclusion. Because cod liver oil (Omega-3 fatty acids) has the ability to reduce the inflammatory response, it is thought to reduce heart disease. Given the hypothesis that the inflammatory response plays an important role in causing prostate cancer, cod liver oil has the potential to prevent the development of prostate cancer. However, the results of studies on cod liver oil and the risk of developing prostate cancer are inconsistent. Epidemiological evidence suggests that the risk of developing prostate cancer is negatively associated with UV exposure, which promotes the conversion of cutaneous vitamin D to active vitamin D. This observation has led some to believe that the higher rate of prostate cancer in the elderly may be due in part to reduced sun exposure in the elderly or to the body’s decreased ability to produce vitamin D as we age. Some people may wonder why black people, who receive more sun exposure, have the highest incidence of prostate cancer among all races. In fact, black skin has the lowest rate of conversion to UV light. However, several recent studies have found no link between vitamin D levels and prostate cancer risk, and one study even found a higher risk of high-risk prostate cancer in men as vitamin D intake increased. Vitamin intake: We usually consider selenium and vitamin E supplementation to be beneficial in the prevention and treatment of tumors. The National Institutes of Health conducted a large randomized trial of over 30,000 men on whether vitamin E and selenium could prevent prostate cancer. Unfortunately, the study was terminated in the middle of the study because there were no data to show that it prevented prostate cancer alone or when the two were combined. To make matters worse, the latest findings concluded that men who increased their intake of vitamin E and selenium had an increased risk of prostate cancer and that men who increased their selenium had an increased risk of developing diabetes. To date, the medical community has not been able to give specific dietary recommendations for the prevention of prostate cancer. At this time we believe there is no easy alternative to a healthy lifestyle. A healthy lifestyle should be a balanced diet, avoiding excessive nutrition, eating more fruits and vegetables, exercising more, not smoking, and more importantly, maintaining a normal weight, avoiding excessive over-obesity, and maintaining a good mental state are perhaps the best ways to prevent prostate cancer. 4.What are the symptoms of prostate cancer? Early prostate cancer is usually asymptomatic, only a family history of prostate cancer can serve as a reminder to receive early screening related to prostate cancer. If prostate cancer has progressed locally or has metastasized distantly, it will cause corresponding pain and produce symptoms. Possible symptoms include the following: persistent bone pain dull pain in the pelvic area urination-related symptoms such as frequent urination, painful urination, burning sensation, weakness and retention of urine hematuria or painful ejaculation pain in the back, buttocks or thighs loss of appetite and/or weight Note: This patient encyclopedia was written using the “Chinese Guidelines for the Diagnosis and Treatment of Prostate Cancer Note: This patient encyclopedia is based on the “Chinese Prostate Cancer Diagnosis and Treatment Guidelines”, the “European Association of Urology (EAU) Prostate Cancer Diagnosis and Treatment Guidelines”, the “American Urological Association (AUA) Patient Information” and the author’s understanding and experience of prostate cancer diagnosis and treatment. The current version is text-only. We will be updating the content and adding pictures to help readers better understand the prostate