Prostate cancer is an epithelial malignancy of the prostate gland. In 2004, WHO published tumor pathology and genetics of urinary system and male reproductive organs, the pathological types of prostate cancer included adenocarcinoma (acinar adenocarcinoma), ductal adenocarcinoma, urothelial carcinoma, squamous cell carcinoma and adenosquamous carcinoma. Prostate cancer accounts for more than 95% of them. Therefore, prostate cancer we usually refer to as prostate cancer. In 2012, the incidence of prostate cancer in tumor registries in China was 9.92/100,000, ranking 6th among male malignant tumors. The age of onset was at a low level before 55 years old, and gradually increased after 55 years old. The incidence increased with the increase of age, and the peak age was 70 ~ 80 years old. Patients with familial inherited prostate cancer were slightly younger, accounting for 43% of patients aged less than or equal to 55 years old.
The cause of
The incidence of prostate cancer is related to genetic factors. If there is no prostate cancer in the family, the relative risk is 1 and the absolute risk is 8. The relative risk and absolute risk of prostate cancer were 5 and 35 ~ 45 respectively. In addition, the incidence of prostate cancer and sexual activities, dietary habits. Men who are sexually active have an increased risk of prostate cancer. High - fat diet is also associated with morbidity. In addition, the incidence of prostate cancer and race, region, religious beliefs may be related.
Clinical manifestations of
Early prostate cancer is often asymptomatic, with the development of the tumor, the symptoms caused by prostate cancer can be summarized into two categories:
Symptoms of compression
Progressive dysuria can be caused by the gradually increased pressure of the prostate gland on the urethra, which is manifested as fine urinary line, short range, slow urine flow, interrupted urine flow, dripping after urine, endless urine, and labored urination. In addition, there are frequency, urgency, increased nocturnal urine, and even urinary incontinence. Tumor presses rectum to be able to cause defecate difficulty or intestinal obstruction, also can oppress vas deferens to cause ejaculation to lack, oppress nerve to cause perineal ministry ache, can radiate to sciatic nerve.
2. Metastatic symptoms
Prostate cancer can invade the bladder, seminal vesicle, vascular nerve bundle, causing hematuria, blood sperm, impotence. Pelvic lymph node metastasis can cause edema of both lower limbs. Prostate cancer is often prone to bone metastasis, resulting in bone pain or pathological fracture, paraplegia. Prostate cancer can also invade the bone marrow and cause anemia or a decrease in whole blood count.
Clinical diagnosis of prostate cancer mainly relies on digital rectal examination, serum PSA, transrectal prostate ultrasound and pelvic MRI examination, and the sensitivity of CT in the diagnosis of early prostate cancer is lower than that of MRI. Because of the high rate of bone metastasis in prostate cancer, a radionuclide bone scan is usually performed before treatment is determined. The diagnosis of prostate cancer requires pathological examination through prostate biopsy.
The malignant degree of prostate cancer can be evaluated by histological grading. The most commonly used is the Gleason scoring system, which divides the malignant degree of prostate cancer into 2 ~ 10 points according to the sum of the score of primary structural area and secondary structural area in the prostate cancer tissue. The best differentiation is 1+1=2 points, while the worst differentiation is 5+5=10 points.