With the constant improvement of esophageal cancer staging CT, CT examination of the hollow organs have become increasingly prominent in clinical importance. CT can clearly show not only tumor growth, violations of the situation surrounding organs, lymph nodes as well as distant metastasis, and can be integrated CT examination, assessment of the tumor before treatment and reasonable treatment options, it is necessary to Staging CT of the treatment of esophageal cancer before treatment as a routine examination.
Esophageal cancer treatment options CT staging and prognosis of great significance. Generally believed that, I of, II and complete resection of esophageal cancer can do to achieve the radical purpose; III Phase, IV period can not be completely removed, should be chemotherapy, radiotherapy, immunotherapy and other means of comprehensive treatment.
Although the spiral CT scans have been widely used in preoperative staging of esophageal cancer, but the CT scan does not show the organizational structure of esophageal wall, and thus can not distinguish between the Tl and Tz-level esophageal lesions, can not accurately determine the esophagus small muscular involvement (T3 level). Use of CT scan in the diagnosis of esophageal cancer staging, often draw less than the actual staging of the diagnosis. Spiral CT scanning in preoperative staging of esophageal cancer diagnostic accuracy rate of 68.8%, diagnosis of esophageal cancer with invasion of surrounding structures, the accuracy was 69.7%, non-invasive diagnostic accuracy was 97.3%. CT scan size of lymph nodes to determine whether lymph node metastasis of the main criteria, usually larger than lcm lymph node metastasis as a diagnostic standard. But the increase of lymph nodes, enlarged lymph nodes in the chest in particular, may be the inflammatory response but not necessarily cancer metastasis. In the abdominal CT scan, abdominal lymph nodes greater than 0.8cm is considered abnormal. The sensitivity of CT was 48% and specificity was 93%.
Wall thickening according to the degree of cancer, whether the foreign invasion, distant metastasis will be divided into 4 esophageal cancer.
I of: chamber mass, or the limitations of esophageal wall thickening (greater than 3mm, normally less than 3mm);
H period: food wall thickening (greater than 5mm) but not invading the mediastinum or distant metastasis;
E period: food wall thickening (greater than 5mm) and directly invading the surrounding tissue, may have mediastinal lymph node swelling, but no distant metastasis;
N period: esophageal cancer with distant metastasis.
In addition, Botet put the T (primary tumor stage) were divided into four.
T1: tumor 3-5cm;
Tz: tumor 5-15cm;
T3: tumor> 15cm and irregular esophageal adventitia;
T4: tumor invades nearby organs such as the trachea, aorta, or vertebrae.
According to the research showed that CT staging of esophageal cancer and esophageal cancer preoperative MRI T (Botet stage), N stage in the sensitivity, specificity: and there is no difference in accuracy. CT and MRI of esophageal cancer Tl and Tz of the diagnostic accuracy is not high, it is the Tl period (no significant change in esophagus); but the development of esophageal cancer to the T3 and T4 of Time, CT, and [RI not only density of the tumor and surrounding tissue nuances, but also multi-faceted the tumor was careful to distinguish its external aggression, particularly T4 high rate of accuracy. Because CT and MRI have a high fraction, so for the mediastinal and abdominal lymph nodes have a higher recognition.