The role of sequential 18^F‐FDG PET/CT in predicting tumour response after preoperative chemoradiation for rectal cancer

Abstract

Differences in the SUV/metabolic area with 18F-fluorodeoxyglucose (18(F) -FDG) PET/CT have the potential to predict a response to preoperative CRT for rectal cancer.

The role of diffusion-weighted MRI and 18F-FDG PET/CT in the prediction of pathologic complete response after radiochemotherapy for rectal cancer: A systematic review

“…A higher decrease in SUV was found predictive for pCR by seven authors [26,41,44,45,[50][51][52]. Optimal cutoff values for RI SUVmax post vary from 45.9% to 76%.…”

“…Pooled data show qualitative analysis after RCT is able to assess pCR with a negative predictive value of 89% and an overall accuracy of 65%, which is comparable to the quantitative SUV measurements post-RCT. Three articles investigated changes in MTV and TLG as a response parameter, but only Sun and co-workers found a relative decrease in MTV and TLG after 5-7 weeks significantly predictive for pCR [47,49,52].…”

Assessing pathological complete response to neoadjuvant chemoradiotherapy in locally advanced rectal cancer: a systematic review

“…Sun et al . studied the ability of 18‐FDG PET/CT at three time points to assess pCR. Parameters assessed included SUVmax, SUVmean, total lesion glycolysis (TLG), metabolic tumour volume (MV) and the response indices of these values.…”

“…A complete metabolic response (CMR) on PET/CT does not always equate to a pCR on histological examination [46]. Five studies investigated the percentage change in maximal standardized uptake values (SUV-max) before and after nCRT and the assessment of pCR [49,[51][52][53][54]. Shanmugan et al [49] found that a 63% reduction in SUVmax predicted pCR with a sensitivity of 60% and specificity of 83%.…”

Volumetric Parameters Changes of Sequential 18F-FDG PET/CT for Early Prediction of Recurrence and Death in Patients With Locally Advanced Rectal Cancer Treated With Preoperative Chemoradiotherapy

“…Several previous studies investigated the predictive value of sequential 18 F-FDG PET/CT for metabolic tumor response in LARC. [20][21][22][23][24][25][26] Especially, using volumetric parameters of 18 F-FDG PET/CT, Sun et al 24 concluded that 18 F-FDG PET/CT is a promising tool for evaluating the response to neoadjuvant CCRT in LARC patients. The percentage change in MTVand TLG between baseline and presurgery PET/CT scans, which reflects the status of the entire tumor mass, may be more reliable for prediction of the pathological response.…”