Use of PET SUV for primary tumor to predict outcome in locally advanced esophageal cancer treated with trimodality therapy

Abstract

e15559 Background: To assess the value of the primary tumor's SUVmax (PT-SUVmax) from the staging FDG-PET as a predictor of clinical and pathologic outcomes in patients undergoing trimodality therapy for locally advanced esophageal cancer. Methods: A retrospective chart review was conducted on patients with T3/4 and/or node positive esophageal carcinoma treated at the Cleveland Clinic between 7/1/03 and 5/31/06. All patients were managed with an institutional regimen consisting of preoperative radiotherapy [30 Gy @ 1.5 Gy twice daily over two weeks] with concurrent cisplatin and 5-fluorouracil during the first week. Following resection, an identical postoperative course of concurrent chemoradiotherapy (CRT) was delivered. Pretreatment patient and tumor characteristics including PT-SUVmax were analyzed with respect to response and survival. Results: 141 patients completed preoperative CRT: 125 (88.7%) were male, median age was 60 years, 73.8% had adenocarcinoma, 79.4% had N1 disease, 81.6% underwent surgery and 63.8% completed the full regimen. Median follow-up was 17.2 months [range 0.7–75.1]. Median PT-SUVmax was 9.43 [range 0 to 47.7]. Increasing clinical stage was associated with increasing PT-SUVmaxs: for cT2 vs. cT3 and cN0 vs. cN1, PT-SUVmax cutoffs were 8 (p=0.03) and 11 (p=0.02), respectively. Median (MST) and 5-year overall survivals were 20.7 months and 27.4%, respectively. A PT-SUVmax of < vs. > 7 was a significant predictor for T downstaging (p=0.0502) and N downstaging (p=0.0467). A PT-SUVmax cutoff of 7.6 was associated with a significant difference in MST, at 29.1 and 13.0 months for PT-SUVmax< 7.6 and >7.6, respectively (p=0.0158, HR=1.82, 95%CI=1.19–2.94). On multivariate analysis, PT-SUVmax was the only significant factor associated with survival (p=0.0.314, HR=1.71, 95%CI=1.05–2.79). Conclusions: The pretreatment SUVmax of a primary esophageal cancer appears to correlate with clinical stage, pathologic response to therapy and survival. This finding could play a role in the design of clinical trials and in adapting treatment strategies. No significant financial relationships to disclose.