The predictive value of treatment response using FDG PET performed on day 21 of chemoradiotherapy in patients with oesophageal squamous cell carcinoma. A prospective, multicentre study (RTEP3).
Fiche publication
Date publication
septembre 2013
Auteurs
Membres identifiés du Cancéropôle Est :
Pr OLIVIER Pierre
Tous les auteurs :
Palie O, Michel P, Menard JF, Rousseau C, Rio E, Bridji B, Benyoucef A, Meyer ME, Jalali K, Bardet S, M'vondo CM, Olivier P, Faure G, Itti E, Diana C, Houzard C, Mornex F, Di Fiore F, Vera P
Lien Pubmed
Résumé
PURPOSE: FDG PET has been suggested to have predictive value in the prognosis of oesophageal carcinoma. However, the retrospective studies reported in the literature have shown discordant results. Additionally, only four studies have evaluated FDG PET during chemoradiotherapy (CRT) in patients with different histological lesions. The purpose of this study was to investigate the predictive value of FDG PET performed early during CRT (on day 21) in a population of patients with oesophageal squamous cell carcinoma. METHODS: Included in this prospective study were 57 patients with a histological diagnosis of squamous cell carcinoma of the oesophagus. Of these 57 patients, 48 (84%) were evaluated (aged 63 +/- 11 years; 44 men, 4 women). Each patient underwent FDG PET (4.5 MBq/kg) before CRT, according to the Herskovic protocol (t0; PET(1)) and on day 21 +/- 3 from the start of CRT (d21; PET(2)). The response assessment included a clinical examination, CT scan or FDG PET and histological analysis 3 months and 1 year after PET(1). The patients were classified as showing a complete response (CR) or a noncomplete response. A quantitative analysis was carried out for PET(1) and PET(2) using the following parameters: SUVmax, SUVmean (with SUVmean40 as the 3-D volume at an SUVmax threshold of 40% and SUVmeanp as that defined by a physician), tumour volume (TV, with TV40 defined as the TV at 40% of SUVmax, and TVp as that defined by a physician); and the total lesion glycolysis (TLG, SUVmean x TV, with TLG(4)(0) defined as the TLG at 40% of SUVmax, and TLGp as that defined by a physician). The differences in responses at 3 months and 1 year between PET(1) (t0) and PET(2) (d21) were assessed in terms of variations in SUV, TV and TLG using a repeated measures of variance (ANOVA). RESULTS: SUVmax, SUVmean and TLG decreased significantly between PET(1) (t0) and PET(2) (d21; p < 0.0001). The TV significantly decreased only when assessed as TVp (p = 0.02); TV(4)(0) did not decrease significantly. With respect to the predictive value of PET(1), only TV40_1 and TVp_1 values, and therefore TLG40_1 and TLGp_1, but not the SUV values, were significantly lower in patients with CR at 3 months. SUVmax1, TVp_1 and TLGp_1 were significantly lower in patients with CR at 1 year. With respect to the predictive value of PET(2), only TV40_2 and TVp_2 values, and therefore TLG40_2 and TLGp_2, but not the SUV values, were significantly lower in patients with CR at 3 months. None of the PET(2) parameters had significant value in predicting patient outcome at 1 year. The changes in SUVmax, TV(4)(0), TVp, TLG(4)(0) and TLGp between PET(1) and PET(2) had no relationship to patient outcome at 3 months or 1 year. CONCLUSION: This prospective, multicentre study performed in a selected population of patients with oesophageal squamous cell cancer demonstrates that the parameters derived from baseline PET(1) are good predictors of response to CRT. Specifically, a high TV and TLG are associated with a poor response to CRT at 3 months and 1 year, and a high SUVmax is associated with a poor response to CRT at 1 year. FDG PET performed during CRT on day 21 appears to have less clinical relevance. However, patients with a large functional TV on day 21 of CRT have a poor clinical outcome (ClinicalTrials.gov NCT 00934505).
Référence
Eur J Nucl Med Mol Imaging. 2013 Sep;40(9):1345-55