1.Q: What is the incidence of prostate cancer in China?
A: The incidence of prostate cancer has obvious geographical and racial differences. In developed countries and regions such as Europe and America, it is the most common malignant tumor in men, and its mortality rate ranks second among all kinds of cancers; in Asia, its incidence rate is lower than that of western countries, but it has been on a rapid rise in recent years. The incidence of prostate cancer in China has been increasing. In 1993, the incidence of prostate cancer in China was 1.71 patients per 100,000 people per year; in 1997, the incidence rose to 2.0 patients per 100,000 people per year, and in 2000, it rose to 4.55 patients per 100,000 people.
The incidence rate of prostate cancer in genitourinary system malignant tumors in Shanghai in 2007 has jumped from the 3rd place to the first place, and has rapidly risen from the 9th place to the 5th place in the ranking of top 10 male tumors. It is predicted that in 10 years, the incidence of prostate cancer in Shanghai will be promoted to the top three among malignant tumors in men.
2.Q: Why are most of the prostate cancer cases found in China at advanced stages?
A: It is mainly related to the lack of awareness and attention to prostate cancer. The current medical technology and level in China can fully detect and treat prostate cancer at an early stage. However, early prostate cancer does not have any symptoms, so it is not easy to attract people’s attention, and it is difficult to be detected if you do not go to a urologist. In developed countries, screening for prostate cancer is one of the mandatory health check-ups for middle-aged and elderly men, but this is not yet possible in China. If men over the age of 50 and men over the age of 40 who have a family history of prostate cancer are examined twice a year, most patients can be detected early.
3. Q: Why does prostate cancer occur?
A: The true cause and pathogenesis of prostate cancer is not well understood. However, prostate cancer occurs in older people, and the older the age, the higher the incidence. In addition, the incidence of prostate cancer varies greatly among different ethnic groups, and the high incidence among people with a family history of prostate cancer indicates that there is also a relationship with heredity. The higher the standard of living, the more fat, protein and cholesterol in the diet, the higher the incidence of prostate cancer.
4.Q: Will prostatitis turn into prostate cancer?
A: Prostatitis mainly occurs in young people, most of them are chronic non-bacterial prostatitis, and only a few are bacterial prostatitis. The pathogenesis of chronic non-bacterial prostatitis is not clear. The pathogenesis of prostate cancer is not clear, but many facts suggest a close association with androgens. To date for this, there is no evidence that prostatitis can be transformed into prostate cancer.
5.Q: Are prostate stones related to prostate cancer?
A: During health exams, ultrasound exams often report prostate stones or calcifications. It is difficult to read books about this aspect of prostate stones, and many careful people are often worried about prostate stones or calcification. This is especially true for the elderly, who have an enlarged prostate and stones, which is not an added problem. In fact, prostate stones are not harmful to the human body, they are located in the glandular ducts of the prostate gland and do not grow into large stones, neither do they affect urination, nor do they lead to prostate cancer.
6. Q: Will prostate enlargement turn into prostate cancer?
A: Prostate enlargement is also a common disease in older men, which can cause difficulty in urination, but it is a benign disease. There is no evidence that prostate enlargement can be transformed into prostate cancer, but prostate enlargement can coexist with prostate cancer.
7. Q: Why does prostate cancer still occur after prostate enlargement surgery?
A: Prostate hypertrophy occurs mainly around the urethra, while the normal prostate tissue in the peripheral area is squeezed and turned into a membrane-like thing, medically called the prostate surgical envelope. The surgery for prostate enlargement is to remove the enlarged prostate within the surgical envelope and the surgical envelope is preserved, which means that the peripheral area of the prostate is preserved. Therefore, the surgery for prostate enlargement does not remove the entire prostate, but preserves a portion of it. This is a very important part of the body, and it is a good place for prostate cancer to occur. Therefore, after the prostate enlargement surgery, not only may there be a recurrence of prostate enlargement, the risk of prostate cancer still exists and needs to be reviewed regularly, not to be paralyzed.
8.Q: What are the risk factors of prostate cancer?
A: The exact cause of prostate cancer is not yet clear, but may be related to genetic changes. For example, changes in androgen receptor-related genes can lead to an increased risk of prostate cancer; men with the BRCA1 gene have three times the risk of prostate cancer than men without the BRCA1 gene; and abnormalities in the P53 gene are closely related to high-grade, highly aggressive prostate cancer. Genetic alterations may also be associated with environmental factors such as diet. The more genetic alterations there are, the greater the risk of prostate cancer. In a few cases, prostate cancer may be hereditary. The risk factors associated with the development of prostate cancer have been summarized as follows
(1) Age: Age is the main risk factor for prostate cancer. Prostate cancer is very rare in men younger than 45 years of age, but the incidence of prostate cancer increases dramatically with age, with the majority of prostate cancer patients older than 65 years of age. Basically, the incidence of prostate cancer almost doubles with every 10-year increase in age after 40 years, with the risk of prostate cancer in men aged 50-59 years being 10%, while the risk of prostate cancer in men aged 80-89 years increases steeply to 70%.
(2) Family history: When an immediate male relative in the family has prostate cancer, the incidence rate of men in the family is significantly higher. Immediate male relatives are usually the father and brothers. If one immediate male relative has prostate cancer, the probability of developing prostate cancer is one time higher than in the general population; if there are two, it will be three times higher. This suggests that the development of prostate cancer may be linked to a gene or group of genes in the body that have not been fully identified by scientists to date.
(3) Ethnicity: The incidence of prostate cancer is highest in African Americans (i.e., black Americans), followed by Hispanics and Caucasian Americans, while the incidence of prostate cancer in black Africans is the lowest in the world. The incidence of prostate cancer in Asian men living in the United States is lower than in Caucasians, but significantly higher than in native Asian men. Although the incidence of prostate cancer among yellow men has not yet reached the level of European and American countries, the incidence of prostate cancer in both China, Taiwan, Hong Kong, and Japan, Korea, and Singapore has shown a trend of increasing year by year.
(4) Abnormal cellular pathological changes in the prostate: Men with high-grade intraepithelial neoplasia of the prostate have a significantly higher incidence of prostate cancer. (4) High-grade intraepithelial neoplasia is a precancerous lesion that shows abnormal cell growth patterns under the microscope, which is not cancerous but often suggests the presence of prostate cancer that has just not been detected.
(5) Diet: Some studies have shown that men who regularly consume foods high in animal fat are also at risk for prostate cancer because of the high levels of saturated fatty acids in these foods. Findings from studies in 32 countries found that prostate cancer mortality was associated with total fat intake. Whereas people whose usual diet is rich in vegetables and fruits are less likely to develop the disease.
(6) Androgen level: High androgen level in the body is also one of the possible triggers of prostate cancer. Androgens can promote the growth of prostate cancer.
The increase in the prevalence of prostate cancer among Chinese residents is related to the aging of the population, improvement in living standards, changes in diet structure and environmental pollution. The results of the study showed that smoking, alcohol consumption, divorce or widowhood, as well as regular consumption of milk, more eggs and pork are the main risk factors for prostate cancer in Chinese people; while eating green vegetables, fruits and legumes are important protective factors.
9.Q: How to screen for early detection of prostate cancer?
A: Early detection of prostate cancer requires universal prostate screening. The easiest way to screen for prostate cancer is a combination of rectal examination of the prostate and serum PSA testing, both of which play a very important role in screening. The vast majority of prostate cancers are detected by abnormal PSA, accounting for 80% of cases, while only 20% of cases are found to have nodal abnormalities on rectal screening. The frequency of prostate cancer screening should ideally be once a year. If progressive increases in PSA levels and/or abnormalities on rectal exam are found during annual screening, further testing is needed. With prostate cancer screening, the incidence of prostate cancer-related complications and prostate cancer-related mortality can be reduced, which can effectively improve survival rates. Usually men should start prostate cancer screening at the age of 50; if there is a family history of prostate cancer, prostate cancer screening should be started at the age of 40.
10.Q: What are the types of prostate cancer?
A: More than 95% of prostate cancers are adenocarcinomas that occur in the prostate gland tissue. Another important type of prostate cancer is neuroendocrine carcinoma, or small cell undifferentiated carcinoma, which may originate from neuroendocrine cells rather than from the prostate gland. This type of prostate cancer usually metastasizes and spreads earlier, but does not secrete prostate-specific antigen (PSA) and is less susceptible to chemotherapy than conventional prostate cancer treatments. In addition, some less common malignancies can occur in the prostate, such as rhabdomyosarcoma, smooth muscle sarcoma, malignant nerve sheath (membrane) tumors, malignant mesenchymal tumors, and malignant tumors from other organs that metastasize to the prostate. Patients with these rare tumors generally have no significant increase in serum PSA values, and the tumors are generally large in size, often producing localized compression of adjacent organs, and most patients present to the doctor with difficulty in urination and/or defecation.
11.Q: What are the clinical manifestations of prostate cancer?
A: Because prostate cancer mostly originates in the peripheral zone of the prostate gland, it is insidious in origin and grows slowly, so early prostate cancer may not have any premonitory symptoms, but only elevated serum PSA value and/or abnormal prostate changes found during screening and/or rectal examination. Once symptoms appear, it is often a more advanced progressive prostate cancer
(1) If the tumor of the prostate gland is progressively enlarging and compressing the urethra of the prostate gland, it may lead to urinary disorders, such as progressive difficulty in urination (thinning of urine stream, skewed urine stream, bifurcation of urine stream or prolongation of urine journey), frequent urination, urgent urination, painful urination, incomplete urination, and in severe cases, dribbling and retention of urine. These symptoms are similar to those of benign prostatic hyperplasia (BPH) and are easily misdiagnosed and missed, delaying early diagnosis and early treatment of the disease.
(2) For advanced progressive prostate cancer, symptoms such as fatigue, weight loss, and generalized pain may occur. As the pain seriously affects the diet, sleep and spirit, after long-term torture, the general condition becomes weaker and weaker, with wasting and weakness, progressive anemia, and eventually cachexia with general failure.
(3) When prostate cancer metastasizes to bone, it can cause bone pain at the metastatic site. Common sites of bone metastasis include the spine, hip, ribs and scapula. Bone pain occurs in about 60% of patients with advanced disease, commonly in the lumbar, sacral, hip and hip pelvis.
(4) Prostate cancer is usually not accompanied by hematuria and hematospermia; however, once hematuria and hematospermia occur, you should go to the urology clinic for relevant examinations to exclude the possibility of prostate or seminal vesicle gland tumors.
12.Q: How to effectively check and confirm prostate cancer diagnosis?
A: Pathological examination of prostate puncture biopsy is currently the gold standard for prostate cancer diagnosis. The so-called pathological diagnosis is made by removing the tumor completely or cutting a part of the tumor tissue, and after many steps of processing, the pathologist will analyze and judge the final diagnosis of the tumor by observing the morphology and other intrinsic characteristics of the tissue cells through microscope.
The main other examinations are: ECT bone scan, chest CT, internal organ ultrasound, pelvic MRI or CT, etc. The purpose of doing these tests is mainly to make a comprehensive assessment of the disease, to determine whether the disease is early or advanced, and whether the tumor is confined to the prostate or has metastasized to distant organs or lymph nodes. For example, chest CT can observe whether there are lung metastases; internal ultrasound can observe whether there are metastases in the liver, spleen, kidneys and other important organs; ECT bone scan is more important to identify whether there are bone metastases; pelvic MRI or pelvic CT can determine whether there are enlarged pelvic lymph nodes; and MRI can further observe whether there is local outward invasion of the prostate to the seminal vesicle gland, rectum and bladder neck. The results of these examinations play a decisive role in the choice of treatment plan for patients.
13.Q: What treatments are available for prostate cancer?
A: There are several treatment methods for prostate cancer, each of which has its own advantages and disadvantages. According to the purpose of treatment, prostate cancer treatment methods are divided into curative treatment and palliative treatment. Palliative treatment aims at delaying tumor progression and relieving tumor-related symptoms.
(1) Radical surgery. Surgery is the most commonly used curative treatment method, called radical prostate cancer surgery, to remove the prostate and tumor intact. Radical prostate cancer surgery can be performed by the retropubic route (incision from the umbilicus to the upper border of the pubic bone), the trans-perineal route (incision between the scrotum and the anus), open, laparoscopic or robotic-assisted radical prostate cancer surgery. Selection of the appropriate surgical approach according to the patient’s body type and disease characteristics, as well as the surgeon’s technical expertise.
(2) Extracorporeal EBRT (abbreviated as EBRT): a new method of applying external radiation therapy to prostate cancer. By increasing the maximum dose of radiation to the prostate area while reducing the dose to the surrounding prostate tissue, it can reduce the adverse effects of traditional external radiation therapy and improve the therapeutic effect.
(3) Radioactive particle implantation therapy (brachytherapy): radioactive particles are implanted into the prostate through the skin of the perineum to kill prostate cancer by brachytherapy, which is one of the curative treatments for prostate cancer because it is less damaging and usually does not require other treatment aids. Depending on the grading, stage and PSA value of the tumor, radioactive particle implantation therapy can be further followed by extracorporeal conformal radiation therapy.
(4) Cryotherapy: It is a minimally invasive treatment, in which a probe is placed into the prostate through the perineal skin under ultrasound guidance, and 2 cycles of argon ultra-low temperature freezing and helium rewarming kill the tumor cells. Currently, cryotherapy has become an effective treatment option for limited prostate cancer and is particularly suitable for patients with low-risk limited prostate cancer who are of advanced age and have many concomitant diseases.
(5) High-energy focused ultrasound therapy and radiofrequency ablation of intra-tissue tumors: also a local treatment method still in the experimental stage. Compared to radical prostate cancer surgery and radiotherapy, their effectiveness in treating clinically limited prostate cancer is not well established and needs to be evaluated in more clinical studies.
(6) Endocrine therapy for prostate cancer: It is a palliative treatment that includes medication, injections, medication combined with injections, and bilateral orchiectomy. By removing or blocking the effect of testosterone (i.e. androgens) on prostate cancer cells in order to temporarily inhibit the growth of prostate cancer cells and slow down the progression of the disease.
(7) Chemotherapy: Used to treat patients with metastatic prostate cancer that is resistant to endocrine therapy in an effort to slow tumor growth and prolong the patient’s life. Studies have demonstrated that docetaxel is effective in extending the survival time of patients with endocrine therapy-resistant prostate cancer; and cabazitaxel can further extend the survival time of those patients who have failed docetaxel treatment. Many clinical trials are investigating new drugs and drug combinations with the goal of finding more effective treatments with fewer adverse effects. Abiraterone is one of the most clinically useful new drugs, with high efficiency for endocrine therapy-resistant prostate cancer.
(8) Nucleotide therapy: It is a palliative treatment used to treat patients with bone pain from bone metastases from prostate cancer. Intravenous or oral diphosphonates may also be used to treat bone pain due to bone metastases.
(9) Other treatments: Other treatments such as biologic targeted therapy are still in clinical trials.
14.Q: Is the prognosis of prostate cancer good?
A: Prostate cancer is one of the tumor types with a good prognosis. The chance of distant metastasis in early stage prostate cancer is 8-20%, with a 5-year survival rate of over 95% and a 10-year survival rate of over 90% after effective treatment. Even in advanced metastatic prostate cancer, the 5-year survival rate is more than 70%.
15.Q: How to prevent prostate cancer?
A: Many dietary factors can increase the risk of prostate cancer. Several studies have shown that a high-fat diet can stimulate prostate cancer growth. Beef and high-fat dairy products appear to be stimulants for prostate cancer, and high intake of dairy products can increase the risk of prostate cancer; conversely, fruits and vegetables and a low-fat diet may help reduce the risk of prostate cancer. These healthy foods include soy (tofu and soy milk), tomatoes, pomegranates, green tea, red grapes, strawberries, blueberries, peas, watermelon, rosemary, garlic, and citrus.
Soy contains phytoestrogens, similar to estrogen in women. Phytoestrogens in dietary dose conditions (the dose contained in normal foods, not supplemental doses) can reduce the risk of prostate cancer.
Green tea contains a variety of antioxidants, with the main components at work being tea polyphenols and catechins compounds. The antioxidant components of green tea have a significant inhibitory effect on the malignant transformation of cells induced by a variety of carcinogens, including aflatoxins, benzo(a)pyrene, cigarette carcinogens, and amino acid cleavage products, helping to stabilize cell structure and reduce cell damage.
Many fish such as salmon, tuna, sardines and herring are rich in Omega 3 fatty acids, which have both cardiovascular disease and cancer prevention effects.
Minerals play a very important role in the growth and normal functioning of the body. Selenium is an important antioxidant and scientists have found that it has an anti-cancer effect and can reduce the incidence of prostate cancer by up to 70%, so it can be consumed in appropriate amounts. Dietary selenium is mainly found in foods such as animal liver, seafood, whole grains, milk and dairy products, mushrooms, garlic and asparagus, and the amount of cancer prevention is 100 to 200 micrograms per day. White melon seeds contain essential zinc, which helps the body repair wounds, promotes cell regeneration and fights free radicals. The intake of zinc for adults is 15 mg per day. The body’s immunity decreases when zinc is deficient, although there is no positive evidence that zinc can reduce the incidence of prostate cancer.
Recent studies have found that the popular crimson pomegranate juice also has anti-prostate cancer properties. Pomegranate juice is rich in antioxidants, the chemicals that give fruits and vegetables their darker color, and it resists damaging cells that can then develop into cancer or other diseases. A recent study showed that drinking a glass of pomegranate juice a day significantly slowed the growth of malignant tumors in prostate cancer patients. Prostate cancer patients who were asked to drink one glass of pomegranate juice (225 ml) a day had significantly slower progression – their PSA levels only increased by a factor of one after 54 months. The use of pomegranate juice for adjuvant therapy was not only effective, but also did not produce other adverse effects.
Lifestyles conducive to prostate cancer prevention.
(1) Maintain an appropriate body weight.
(2) Adhere to physical exercise, which should be appropriate.
(3) Choose a plant-based diet.
(4) Do not smoke and do not abuse alcohol.
(5) Limit fat intake to no more than 20% of total caloric intake.
(6) not eating junk food and avoiding saturated fats in the diet as much as possible
(7) Eat more fish, which is rich in certain beneficial fatty acids.
(8) Eating 7 to 9 meals a day of fruits and vegetables and limiting sugar and salt intake, both to prevent cancer and to keep the heart healthy.
(9) Consuming more fiber-rich foods, at least 30 grams per day.
(10) Consuming soy products once or twice a day, which can be low-fat soy milk, tofu, soy protein powder, etc.
(11) Take adequate doses of calcium and vitamin D to prevent osteoporosis.