Radiological Imaging in Patients with Esophageal Carcinoma

Abstract

Diagnostic imaging is carried out in patients with esophageal carcinoma in order to decide on the therapeutical procedure, to control therapy, to document complications and to assess concomitant diseases. Chest X-rays and esophagograms give a 2-dimensional view of the X-ray absorption in 3-dimensional examination volumes, the diagnostic accuracy thus being limited by overshadowing. Because of the robust examination technique, the broad availability and the low costs chest X-rays are usually used for short-term controls under therapy and follow-up. Esophagography is carried out in order to asses the exact location and length of a known esophageal carcinoma prior to therapy and in order to assess peristaltic disturbances and fistulas. CT and MRI provide tomographic images with a spatial resolution of up to 1 mm3 allowing the reconstruction of high-resolution images not only in the transversal but also in any other plain. The diagnostic accuracy of esophagography is comparatively high in T1--T3 stages (80%--90%). T1 and T2 tumors cannot be diagnosed by CT and MRI, because both methods do not visualize the mucosa (unlike esophagography and endoscopy) and the esophageal wall layers (unlike EUS). Infiltration depth tends to be overestimated in T1 and T2 carcinomas and to be underestimated in T3 and T4 cancers. CT and MRI cannot detect metastases in normally sized lymph nodes and cannot accurately differentiate between benign and malignant lymphadenopathy in enlarged nodes with a reported sensitivities and specifities of 60% and 74%, respectively. However, further prospective studies using up to date CT and MR technology are needed to assess the present diagnostic situation. CT and MRI do not only visualize the mediastinum, but also the lungs, the pleura and the skeleton as well as the neck and the abdomen thus providing a comprehensive overview of the TNM stage in 3 body regions.