Effects of neoadjuvant radio-chemotherapy on 18 F-FDG-PET in esophageal carcinoma I. Brink a, *, M. Hentschel a , T.A. Bley c , A. Walch d , M. Mix a , M. Kleimaier a , E. Moser a , A. Imdahl b a Division of Nuclear Medicine, University Hospital Freiburg, Hugstetterstr. 55, 79106 Freiburg, Germany b Department of General Surgery, University Hospital Freiburg, Hugstetterstr. 55, 79106 Freiburg, Germany c Division of Diagnostic Radiology, University Hospital Freiburg, Hugstetterstr. 55, 79106 Freiburg, Germany d Department of Pathology, University Hospital Freiburg, Hugstetterstr. 55, 79106 Freiburg, Germany Accepted for publication 4 March 2004 KEYWORDS Esophageal cancer; Positron emission tomography; 18F- fluorodeoxyglucose; Neoadjuvant radio- chemotherapy Summary Aim. To investigate whether results of [F-18]-fluorodeoxy-D-glucose (FDG) positron emission tomography (PET) of esophageal cancer (EC) before and after neoadjuvant radio-chemotherapy correlate with histopathology after esophageal resection. Methods. Twenty consecutive patients with EC without distant metastases were examined twice with 18 F-FDG-PET during primary staging and after neoadjuvant radio- chemotherapy. FDG standardised uptake values (SUV) were correlated with the histopathological findings (percentage of viable tumour cells, tumour regression grade 1–5). Results. Regression analysis revealed a slight (not significant) positive correlation between SUV pre (R ¼ 0.41, p ¼ 0.08) and SUV post (R ¼ 0.37, p ¼ 0.11) and the percentage of viable tumour cells in the resectate. Although all patients showed a significant decrease in SUV after radio-chemotherapy ðp , 0:01Þ; the percentual decrease of the SUV after therapy (DSUV % ) did not significantly differ between the TRG-groups. In 12 of 20 patients (60%), therapy-induced esophagitis was detected in post-therapeutic PET images. Conclusion. In EC, a higher pre-therapeutic SUV might be correlated with a higher fraction of vital tumour cells remaining after radio-chemotherapy. Applying the neoadjuvant therapy protocol and the study design used in this examination, there is no correlation between decrease in SUV and histopathology. Q 2004 Elsevier Ltd. All rights reserved. Introduction The therapy of choice in non-metastatic esophageal carcinoma (EC) is surgical resection of the primary tumour. Preoperative radio-chemotherapy is not generally established but is increasingly applied for local downstaging and systemic disease control. 1–3 A pathologic complete response to neoadjuvant therapy is the strongest predictor of long-term survival. 4 However, more than half of patients with solid carcinomas have poor response to this neoadjuvant therapy. 2,3,5,6 There are presently no EJSO (2004) 30, 544–550 www.ejso.com 0748-7983/$ - see front matter Q 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.ejso.2004.03.007 *Corresponding author. Tel.: þ 49-761-2703999; fax: þ 49-761- 2703930. E-mail address: ibrink@ukl.uni-freiburg.de