SYNCHRONOUS PRIMARY NEOPLASMS DETECTED ON POSITRON EMISSION TOMOGRAPHY IN STAGING OF PATIENTS WITH ESOPHAGEAL CANCER

Introduction: Because of improvements in diagnostic technology, the incidental detection of synchronous primary tumors during the preoperative work-up of patients with esophageal cancer has increased. The aim of this study was to determine the rate and clinical relevance of synchronous neoplasms seen on FDG-PET in staging of esophageal cancer. Methods: From January 1996 to July 2004, 366 patients with biopsy-proven malignancy of the esophagus underwent FDG-PET for initial staging. This series of patients was retrospectively reviewed for the detection of synchronous primary neoplasms. Results: Twenty synchronous primary neoplasms were identified in 366 patients (5.5%). Eleven neoplasms were localized in the colorectum, 5 in the kidney, and 2 in the thyroid gland, 1 in the lung, and 1 in the gingiva. One of the thyroid lesions and the lung lesion were erroneously interpreted as metastases, leading to incorrect upstaging of the esophageal tumor. Conclusions: FDG-PET detected unexpected synchronous primary neoplasms in 5.5% of patients with esophageal cancer. Sites of pathologic FDG uptake should be confirmed by dedicated additional investigations before treatment, because synchronous neoplasms may mimic metastases.