18F-FDG PET/CT has a high impact on patient management and provides powerful prognostic stratification in the primary staging of esophageal cancer: a prospective study with mature survival data.

UNLABELLED: The aim of this study is to evaluate the incremental staging information, management impact, and prognostic stratification of PET/CT in the primary staging of esophageal cancer in a cohort of patients with mature survival data. METHODS: Between July 2002 and June 2005, 139 consecutive patients with newly diagnosed esophageal cancer underwent conventional staging investigations (CSI), followed by PET/CT. Disease stage was classified according to the American Joint Committee on Cancer staging system (6th edition) and grouped as stage I-IIA, stage IIB-III, and stage IV reflecting broad groupings that determine therapeutic choice. Validation of results was performed when PET/CT and CSI stage groups were discordant and in those patients where PET/CT changed management. Management impact was determined by comparing prospectively recorded pre-PET/CT management plans with post-PET/CT management plans. Survival after follow-up of at least 5 y in patients was analyzed using the Kaplan-Meier product limit method and the Cox proportional hazards regression model. RESULTS: PET/CT changed the stage group in 56 of 139 (40%) patients and changed management in 47 of 139 (34%) patients. In 22 patients, therapy was changed from curative to palliative and in 3 from palliative to curative; in 11, treatment modality was changed without a change in treatment intent, and in 11 the delivery of therapy or diagnostic procedure was changed. Of the 47 patients with management change, imaging results could be validated in 31 patients, and PET/CT correctly changed management in 26 (84%) of these. Of the remaining 5 patients, CSI stage was also incorrect in 4 and correct in 1. Median survival was 23 mo. PET/CT stages I-IIA, IIB-III, and IV had a 5-y survival of 40%, 38%, and 6%, respectively. Post-PET/CT stage group and treatment intent were both strongly associated with survival (P < 0.001). CONCLUSION: PET/CT provides incremental staging information compared with CSI, changes management in one third of patients, and has powerful prognostic stratification in the primary staging of esophageal cancer.

Findings on 18F-FDG PET scans after neoadjuvant chemoradiation provides prognostic stratification in patients with locally advanced rectal carcinoma subsequently treated by radical surgery.

UNLABELLED: Predicting outcome after aggressive therapy for advanced rectal cancer remains difficult. (18)F-FDG PET has emerged as a valid method for predicting patient outcomes after therapy in an increasing number of cancers. We evaluated the prognostic information obtained from the degree of change in tumor (18)F-FDG PET uptake induced by chemoradiation before radical curative surgery in patients with T3/T4 rectal cancer. METHODS: The study included 34 consecutive patients with T3/T4 Nx M0 rectal cancer on structural imaging, who underwent staging and postchemoradiation (18)F-FDG PET before planned curative surgery. Change in (18)F-FDG uptake was graded visually as complete (CMR), partial (PMR), or no (NoMR) metabolic response. Pre- and postchemoradiation (18)F-FDG PET-derived standardized uptake values (SUVs) were then obtained for PMR patients to determine whether SUV further stratified this subgroup. Operative findings were available in 30 patients (3 excluded because of (18)F-FDG PET-defined M1 disease, 1 refused surgery). Clinical status at study closeout (alive free from disease, FFD; alive with disease, AWD; or died of disease, DOD) was available for all patients. RESULTS: A pathologic complete response was found in only 6 of 30 patients (5 CMR, 1 false-positive PMR). However, after an estimated median 3.1 y of follow-up, all 17 CMR patients were FFD, 6 of 10 PMR patients were FFD, 2 of 10 had DOD, and 2 of 10 were AWD. All 3 NoMR patients DOD. PET response was highly significantly associated with overall survival duration (P < 0.0001) and time to progression (P < 0.0001). Pathologic complete response was the only other statistically significant prognostic factor (P < 0.03). The percentage of maximum SUV change after chemoradiation was not predictive of survival in PMR patients. CONCLUSION: Using a simple qualitative assessment, postchemoradiation (18)F-FDG PET scintigraphy provides good medium-term prognostic information in patients with advanced rectal cancer undergoing radical surgery with curative intent.

Does positron emission tomography change management in primary rectal cancer? A prospective assessment.

PURPOSE: The influence of positron emission tomography in the management of recurrent rectal cancer is well established but its role in primary rectal cancer remains uncertain. This study therefore prospectively assesses the impact of position emission tomography scanning on the management of primary rectal cancer. METHODS: Forty-six patients with advanced primary rectal cancer referred for consideration of adjuvant preoperative therapy underwent position emission tomography scanning. The referring physicians prospectively recorded each patient's stage following conventional imaging and the proposed treatment plan prior to position emission tomography scanning. This was then compared with subsequent stage and actual management implemented, and the appropriateness of position emission tomography-induced changes was noted by subsequent clinical follow-up. RESULTS: The surgical management of 36 of 46 patients (78 percent) was unchanged as a result of position emission tomography, even though position emission tomography upstaged disease in 3 of 36 cases (8 percent) and downstaged disease in 5 of 36 cases (14 percent). In 8 of 46 cases (17 percent), management was altered because of the position emission tomography scan findings, including 6 cases (13 percent) in which surgery was cancelled and 2 other cases (4 percent) in which the radiotherapy field was changed. Where available, follow-up confirmed the appropriateness of position emission tomography-induced management change in each case. Two patients had a change in therapy independent of the position emission tomography scan due to clinical circumstances. Overall tumor stage was changed following position emission tomography in 18 of 46 patients (39 percent). CONCLUSION: Position emission tomography scanning appears to accurately change the stage or appropriately alter the therapy of almost a third of patients with advanced primary rectal cancer. In view of this, we suggest that position emission tomography scanning be considered part of standard workup for such patients, particularly if neoadjuvant chemoradiation is being considered as part of primary management.