Cancer, the tumor is the tumor marker produced by the tumor itself can reflect the presence of chemical substances, called tumor marker. Ideal tumor marker should be specific to tumor tissue but not in normal tissues. Unfortunately, so far not found in normal tissue of colorectal cancer definitely not the specific ingredients, so a tumor marker of colorectal cancer relative to normal tissue is particularly evident in the increase was significant in the chemical composition.
Cancer, the tumor markers (1) carcinoembryonic antigen (CEA) carcinoembryonic antigen initially thought to be a colon cancer specific antigen, but further research found that CEA is present in many organizations, accounting for film elements, so CEA is a non-specific tumor marker. Colorectal cancer, membrane adenocarcinoma, stomach cancer, breast cancer and some other tumors were seen in serum carcinoembryonic antigen levels. CEA more than 20 micrograms / l, often suggestive of gastrointestinal cancer. However, many benign diseases also can cause increased serum CEA, such as benign breast tumor, severe alcoholic liver cirrhosis, emphysema, and collagen disorders, cardiovascular disease, diabetes and non-specific inflammation may also end Jan 15% _53% of elevated serum CEA. Therefore, CEA is not specific markers of colorectal cancer, the diagnosis is only secondary value.
CEA determination and dynamic observation is the best non-invasive examination of the measure, CEA for the prognosis of colorectal cancer have a greater efficacy and clinical value, especially for monitoring blood circulation of cancer treatment associated with muscle antigen in patients with persistent elevation of very important value, it can prompt a transfer of latent and residual cancer. Such as serum carcinoembryonic antigen level and on to the stage colorectal cancer have a clear relationship, the more advanced disease, higher serum carcinoembryonic antigen Wang, child surgery reduced recurrence Shiyou start 1: two liters. Chemotherapy can cause tissue necrosis due to the release of CEA. Carcinoembryonic antigen in blood can be temporarily increased. Pre-treatment before surgery or if not accompanied by increased CEA, the postoperative CEA monitoring of little significance.
Wang preoperative cancer antigen levels were up 6 weeks after radical or should be recovered within 1-4 months, still hold high and may still indicate residual tumor or recurrence. Dynamic observation often prompts I! City bed recurrence or residual, recurrent symptoms are considered in the performance before the 10 weeks to 1 3 months, CEA has increased, so radical surgery for cancer antigen levels were checked and tracking should be closely follow-up, if necessary, to do the second son of the second exploratory surgery. Carcinoembryonic antigen on liver and retroperitoneal metastases sensitive, and in the lymph node and lung metastasis are relatively insensitive.
After cancer, tumor markers (2) CA 19-9 CA19-9 is associated antigen kinds of digestive tract, increases in a variety of adenocarcinomas, especially in colon, shy adenocarcinoma, lung adenocarcinoma and gastric cancer. In the stomach, bile duct gland and Yi month of cancer with high sensitivity.
As with the CEA, the serum CA19-9 can not serve as an early diagnostic test, but as indicators of prognosis and disease tracking is in the affirmative. Determination of CA19-9 levels help determine prognosis. If preoperative CJ .19-9 value is high, patients can be reduced to the normal range. If the patients were followed up for determination of CA19-9, may appear in the radiographic and clinical signs indicate tumor recurrence before. After CJ .19-9 rapidly reduced, if the re-up is often a sign of tumor recurrence.
After cancer, tumor markers (3) CA24-2 CA24-2 is also a tumor marker of gastrointestinal cancer is a tumor associated antigen and the liquid, marking a variety of cloth fluid secreted adenocarcinoma, and the detection of CEA complementary.
As a tumor marker of colorectal cancer are the lack of specificity, using a variety of combined detection of tumor markers can improve the positive rate and specificity of diagnosis. Clinical often choose CEA, CA19-9 and CA24-2 joint detection.