Prostate Cancer and Radiation Therapy

According to the statistics of the Health Department of the Executive Yuan, the incidence and mortality of Chinese prostate cancer are increasing year by year. In the past two years, more than 2,000 new cases have been diagnosed in China every year, accounting for about 90% of male reproductive organ tumors. The prevalence of prostate cancer is between 65 and 75 years. In recent years, due to medical advances, the five-year survival rate of prostate cancer can reach more than 70% through early diagnosis and various effective treatment methods.

Men over the age of 50 should receive routine digital anal examinations and prostate specific antigen tests each year. However, if there is a case of prostate cancer in the family, the annual examination should be started as early as 45 years old. Once a prostate cancer is found, it is most often based on a combination of clinical tumor stage, serum prostate specific antigen (PSA) value, and Gleason score of the prostate section as a reference for deciding how to choose a treatment.

Radiation has been used in the treatment of prostate cancer for many years. Compared with earlier simpler treatment techniques, our hospital currently uses computer tomography to precisely define the location of prostate cancer, coupled with high-energy linear accelerators, increasingly sophisticated computer-assisted treatment planning systems, dose calculation, alloy lead or multi-leaf vision Zhiyi, the so-called intensity-modulated radiation therapy (IMRT), is used in the treatment of prostate cancer. Each point of the tissue in the treatment area can be accurately calculated, so that the tumor dose can be further increased to a very high lethal dose and the dose and side effects of surrounding normal tissue can be reduced. Experience in the past years shows that radiotherapy can indeed control prostate cancer for a long time, and clinical experience has indeed proven that radiotherapy has a good effect. At present, the change of PSA after treatment is used as the evaluation standard for treatment results. During extracorporeal radiation therapy, although some patients had mild rectal and bladder side effects and painless diarrhea, urination problems (urgent, unclean, etc.), or worsening hemorrhoids, they were mostly well tolerated. Most of these acute side effects disappear after a few days of treatment. Late side effects are defined as those that occur 3 months after the end of radiation therapy, and are mostly caused by damage to blood vessels and connective tissues. During this period, the scope of radiotherapy cannot be altered without the permission of the physician. In case of blurred lines, the professional treatment team must re-draw the description to avoid causing wrong treatment fields. Try to avoid washing or rubbing with soap (also within weeks after treatment ends). Patients should avoid applying any lotion or cream without the instructions of a physician to avoid increasing skin reactions. For slight itching, do not use nails to reduce skin irritation and damage. Do not stick with adhesive tape. Patients should wear loose clothing, avoid sunlight, and clothing that can cause friction. After treatment, the skin color becomes darker due to the treatment, and it will naturally fade away, without the need to remove it by external force.

Another radiotherapy option is in vivo brachytherapy using tissue implantation techniques. The therapeutic effect on screened early localized prostate cancer (for 5 and 10-year PSA control situations) is similar to external radiation therapy or prostate eradication. It can be roughly divided into two types of low-dose-rate and high-dose-rate proximity radiotherapy: due to the lack of access to low-dose-rate proximity radiotherapy needles, it is rarely implemented in China; and the more considered method is high-dose-rate proximity radiotherapy. Radiation therapy is supplemented by extracorporeal radiation therapy. Rectal and bladder tissue-transplantation treatments receive less volume of high-dose radiation, which seems to be more likely to reduce side effects in this regard, but the relative acceptance of domestic patients is low and is not universal.