Abstract
GOAL:To determine if the placement of metal endoclips improves radiotherapy (XRT) planning for esophageal cancer.
BACKGROUND:XRT is an important modality in the treatment and palliation of esophageal cancer. Accurate simulation of the radiation field ensures optimal therapy while limiting toxicity.
STUDY:Patients with esophageal carcinoma underwent EGD and endoscopic mucosal clip placement at the proximal and distal margins of the tumor. At XRT simulation the radiation oncologist simulated the field based on barium study, CT scan, and endoscopy report. A second radiation oncologist then assessed the ease of identification of the clips/margins of the tumor, shift in the field isocenter, and change in the radiation field width and length because of the metal clips.
RESULTS:Seven patients with cancer of the esophagus had endoscopic clips placed followed by XRT simulation. The clips could be identified in all 7 patients. Simulation with the use of clips caused a shift in the field isocenter with a mean longitudinal shift (y-axis) of 3.5 cm (range, 1-6 cm) and a mean lateral shift (x-axis) of 0.33 cm (range, 0-1 cm).
CONCLUSIONS:Endoscopically placed mucosal metal clips can aid field simulation when planning radiation therapy in patients with esophageal cancer.