Differences in displacement of the proximal and distal ends of mid-upper thoracic esophageal squamous cell carcinoma

Abstract

Abstract. In the present study, clips were used as markers to evaluate displacement differences between proximal and distal ends of esophageal tumors and to test whether their internal target volume (ITV) margins should be determined separately. A total of 23 patients with mid-upper thoracic esophageal squamous-cell carcinoma, a tumor length of ≤8 cm and an esophageal lumen suitable for endoscopic ultrasonography were recruited for the present study. Clips were implanted endoscopically at the proximal and distal ends of the esophageal tumor (upper and lower clips). In a further exploratory study on 16 of the patients, a third clip was placed at the distal esophagus 2 cm above the gastro-esophageal junction (GEJ) (cardiac clip). The clips were contoured for all 10 phases of the four-dimensional computed tomography and the maximum displacements of the clip centroids among different breathing phases in left-right (LR), superior-inferior (SI) and anterior-posterior (AP) directions were marked as x, y and z, respectively. The ITV margins that covered 95% of the LR, SI and AP motion were 2.89, 5.00 and 2.36 mm, respectively. Axial displacement (y) was greater than radial displacement (x, z; P<0.05). It was also revealed that LR(x), SI(y) and AP(z) displacement of cardiac clips was greater than that of upper or lower clips (P<0.05). Differences in the axial and radial displacement of the upper and lower clips indicated that axial and radial ITV margins should be determined separately. However, further study is required on patients in whom the distal tumor end is located in proximity to the GEJ.

Esophageal motion characteristics in thoracic esophageal cancer: Impact of clinical stage T4 versus stages T1-T3

“…Previous studies indicated that the esophageal tumor motion is variable according to several factors such as the region of the esophagus or the direction of motion. 10 , 11 , 12 , 13 , 14 , 15 , 16 In addition to these factors, our present findings revealed that cT stage also influenced the esophageal motion and the ITV margin in esophageal cancer. If the patient-specific ITV is to be used, the ITV margin should be determined using the several 4D phase images of each patient.…”

“…Several studies reported the ITV margins for primary esophageal tumor. Qiu et al 15 evaluated the displacement differences of markers between proximal and distal ends of tumor and investigated whether the ITV margins should be determined separately in patients with mid-upper thoracic ESCC. The ITV margins that covered 95% of their datasets in the LR, AP, and SI directions were 2.9, 2.4, and 5.0 mm, respectively.…”

“… 9 Several studies that reported on esophageal tumor motion using 4DCT have been published. 10 , 11 , 12 , 13 , 14 , 15 , 16 In those studies, however, the influence of esophageal tumor invasion was not discussed.…”

Screening of Potential Molecular Targets for Proximal, Mid, and Distal Esophageal Cancers

“…The esophagus is a long tubular organ extending from the neck to the upper abdomen, surrounded by various structures [8,9]. Esophageal tumors tend to grow and migrate longitudinally along the esophageal wall.…”