TY - JOUR
T1 - MRI and FDG-PET for assessment of response to neoadjuvant chemotherapy in locally advanced rectal cancer
AU - Aiba, Toshisada
AU - Uehara, Keisuke
AU - Nihashi, Takashi
AU - Tsuzuki, Toyonori
AU - Yatsuya, Hiroshi
AU - Yoshioka, Yuichiro
AU - Kato, Katsuhiko
AU - Nagino, Masato
PY - 2014/6
Y1 - 2014/6
N2 - Background: The purpose of this study was to assess the value of magnetic resonance imaging (MRI) and additional 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) for tumor response to neoadjuvant chemotherapy (NAC) in patients with locally advanced rectal cancer (LARC). Methods: Data on 40 patients with LARC, who were treated with NAC and underwent MRI and FDG-PET/CT before and after NAC, were analyzed retrospectively. Surgery was performed at a median of 6 weeks after NAC and the images were compared with the histological findings. The tumor regression grade 3/4 was classified as a responder. Results: Sixteen patients were pathological responders. Receiver operating characteristic (ROC) analysis revealed that MRI total volume after NAC (MRI-TV2) and ΔMRI-TV had the highest performance to assess responders (area under the ROC curve [AUC] 0.849 and AUC 0.853, respectively). The reduction rate of the maximum standardized uptake value (ΔSUVmax) was also an informative factor (AUC 0.719). There seems no added value of adding FDG-PET/CT to MRI-TV2 and ΔMRI-TV in assessment of NAC responders judging from changes in AUC (AUC of ΔSUVmax and MRI-TV2 was 0.844, and AUC of ΔSUVmax and ΔMRI-TV was 0.846). Conclusions: MRI-TV2 and ΔMRI-TV were the most accurate factors to assess pathological response to NAC. Although ΔSUVmax by itself was also informative, the addition of FDG-PET/CT to MRI did not improve performance. Patients with LARC who were treated by induction chemotherapy should receive an MRI examination before and after NAC to assess treatment response. A more than 70 % volume reduction shown by MRI volumetry may justify the omission of subsequent radiotherapy.
AB - Background: The purpose of this study was to assess the value of magnetic resonance imaging (MRI) and additional 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) for tumor response to neoadjuvant chemotherapy (NAC) in patients with locally advanced rectal cancer (LARC). Methods: Data on 40 patients with LARC, who were treated with NAC and underwent MRI and FDG-PET/CT before and after NAC, were analyzed retrospectively. Surgery was performed at a median of 6 weeks after NAC and the images were compared with the histological findings. The tumor regression grade 3/4 was classified as a responder. Results: Sixteen patients were pathological responders. Receiver operating characteristic (ROC) analysis revealed that MRI total volume after NAC (MRI-TV2) and ΔMRI-TV had the highest performance to assess responders (area under the ROC curve [AUC] 0.849 and AUC 0.853, respectively). The reduction rate of the maximum standardized uptake value (ΔSUVmax) was also an informative factor (AUC 0.719). There seems no added value of adding FDG-PET/CT to MRI-TV2 and ΔMRI-TV in assessment of NAC responders judging from changes in AUC (AUC of ΔSUVmax and MRI-TV2 was 0.844, and AUC of ΔSUVmax and ΔMRI-TV was 0.846). Conclusions: MRI-TV2 and ΔMRI-TV were the most accurate factors to assess pathological response to NAC. Although ΔSUVmax by itself was also informative, the addition of FDG-PET/CT to MRI did not improve performance. Patients with LARC who were treated by induction chemotherapy should receive an MRI examination before and after NAC to assess treatment response. A more than 70 % volume reduction shown by MRI volumetry may justify the omission of subsequent radiotherapy.
UR - http://www.scopus.com/inward/record.url?scp=84902151154&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84902151154&partnerID=8YFLogxK
U2 - 10.1245/s10434-014-3538-4
DO - 10.1245/s10434-014-3538-4
M3 - Article
C2 - 24531702
AN - SCOPUS:84902151154
SN - 1068-9265
VL - 21
SP - 1801
EP - 1808
JO - Annals of Surgical Oncology
JF - Annals of Surgical Oncology
IS - 6
ER -