Prospective study on the FDG–PET/CT predictive and prognostic values in patients treated with neoadjuvant chemoradiation therapy and radical surgery for locally advanced rectal cancer

Abstract

Dual-time FDG-PET/CT in patients with LARC treated with NCRT and radical surgery supplies limited predictive information. However, an optimal metabolic response appears associated with a favourable patient outcome.

The Flow–Metabolic Phenotype of Primary Colorectal Cancer: Assessment by Integrated 18F-FDG PET/Perfusion CT with Histopathologic Correlation

“…There is strong circumstantial evidence that hypoxic tumors with high glucose metabolism represent a particularly aggressive tumor type (17)(18)(19) and are associated with greater treatment resistance (18). Identification of these hypoxic yet highly metabolic tumors by imaging may potentially be an effective strategy for stratifying patients for neoadjuvant chemotherapy.…”

Prediction of response to preoperative chemoradiotherapy in patients with locally advanced rectal cancer

“…Various PET-CT parameters have been investigated: mean standardized uptake value (SUVmean), maximum SUV (SUVmax), ΔSUVmax (SUVmax-pre -SUVmaxpost), response index [RI, (SUV pre -SUV post )/SUV pre ), metabolic tumor volume (MTV), ΔMTV% (MTV pre -MTV post )/MTV pre , visual response assessment (VRA), and total lesion glycolysis (TLG, SUVmean × MTV) ( Table 2) (19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31)(32). These studies were able to establish a correlation between PET-CT results and CRT response (22)(23)(24)(25)(26)(27)(28)(29)(30). Most studies used several parameters but found just one or two parameters correlated with CRT response (21)(22)(23)(24)(25)(26)(27).…”

“…These studies were able to establish a correlation between PET-CT results and CRT response (22)(23)(24)(25)(26)(27)(28)(29)(30). Most studies used several parameters but found just one or two parameters correlated with CRT response (21)(22)(23)(24)(25)(26)(27). Kim et al used SUVmaxpre, SUVmax-post, ΔSUVmax and RI to assess tumor response.…”

“…Therefore, before ADC can be used as a predictor clinically, large cohort studies are needed. Capirci et al (25) Martoni et al (26) Chennupati et al (27) Kim et al (28) Maffione et al (29) Everaert et al (32) No. SUVmax-post was a significant factor for prediction of downstaging and pCR (28).…”

“…Over the past decades lots of PET-CT parameters have been implemented to assess the CRT response in LARC. RI might be the best parameter for response assessment, especially acquired during therapy (25)(26)(27). The percentage differences in SUV between pre-and post-CRT, especially %ΔSUVmean, can be considered as valuable markers and worth further study (32).…”