OBJECTIVETo evaluate the accuracy of radiographic examination, endoscopic examination and clinical response evaluation criteria in staging for esophageal carcinoma after preoperative chemoradiation therapy(pre-CRT).

METHODSTwenty-seven patients of locally advanced esophageal squamous cell carcinoma were involved. CT scan for cervical part, chest and abdomen, and endoscopic ultrasound(EUS), electronic fibrobroncoscopic examination were used to assess the tumor for staging before pre-CRT. The tumors were re-assessed using the same methods after the completion of CRT. Response evaluation criteria in solid tumors(RECIST) was used to assess the tumor response. Surgery was carried out 3 to 6 weeks after CRT. The clinical tumor response before surgery was compared with pathological tumor response after surgery. Micrometastasis detection was carried out for paraffin embedded lymph nodes using anti-keratin monoclonal marker AE1 and AE3 by immunohistochemical(IHC) method.

RESULTSThe accuracy of CT scan in staging after pre-CRT was 40.9%(9/22) for primary tumors and 68.2%(15/22)for lymph nodes, with overall accuracy of 40.9%(9/22) for TNM staging. The accuracy of EUS in staging was 38.5%(5/13) for primary tumors and 69.2%(9/13) for lymph nodes, with overall accuracy of 38.5%(5/13)for TNM staging. While CT scan combined with EUS, the accuracy for TNM staging was 46.2%(6/13). Five cases achieved CR, 14 cases achieved PR and 8 cases achieved SD according to RECIST. Among 5 clinical CR cases, 3 cases were confirmed by pathologic examination, 1 case was diagnosed as pT(3)N(1) disease by HE stain. One case with pT(0)N(0) disease by HE stain was detected with lymph node micrometastasis by IHC. Among 5 pathological CR cases, 3 cases were diagnosed as clinical CR, 2 cases were diagnosed as clinical PR before surgery. Among 15 cases of N(0) disease by HE stain, 3 lymph nodes from 2 cases were detected with micrometastasis by IHC.

CONCLUSIONSThe current examinations(barium swallow, CT scan,EUS, endoscopy guided biopsy) and RECIST are not accurate enough to assess the tumor response for esophageal squamous cell carcinoma after pre-CRT. Surgery should be recommended for patients with clinical CR after pre-CRT.