Inadequacy of computed tomography in assessing patients with esophageal carcinoma after induction chemoradiotherapy

Abstract

BACKGROUND. Induction chemoradiotherapy followed by surgery may improve survival of patients with esophageal carcinoma. Computed tomography (CT) has been used to evaluate the tumor response after completing induction chemoradiotherapy. The authors examined the ability of CT to evaluate the pathologic tumor response to induction therapy and to stage the tumor correctly. METHODS. Preinduction and postinduction chemoradiotherapy CT scans were reviewed retrospectively for 50 patients enrolled in a protocol of induction chemoradiotherapy followed by surgery. All studies were performed on third-generation or fourth-generation scanners. Radiographic response was determined using Eastern Cooperative Oncology Group solid tumor response criteria for bidimensional measurable disease. This was compared with the pathologic tumor response. CT-tumor (T) classification using the modified Tio scale was compared with the pathologic T classification. RESULTS. CT-T classification did not correlate with the pathologic stage (P = 0.09) or the pathologic tumor response (P = 0.22). The postinduction chemoradiotherapy CT accurately staged the T classification in 42% of patients but overstaged 36% of patients and understaged 20% of patients. CT had a sensitivity of 65%, a specificity of 33%, a positive predictive value of 58%, and a negative predictive value of 41% in evaluating the pathologic tumor response. CONCLUSIONS. CT is a poor diagnostic study tool for determining the pathologic tumor response or the pathologic disease stage after induction chemoradiotherapy in patients with esophageal carcinoma.