The role of ¹⁸F-FDG PET/MRI in assessing pathological complete response to neoadjuvant chemotherapy in patients with breast cancer: a systematic review and meta-analysis

The present study aimed to evaluate the use of ¹⁸F-2-[¹⁸F]-fluoro-2-deoxy-d-glucose (FDG) PET/MRI (Positron emission tomography-computed tomography) in predicting the pathological response to neoadjuvant chemotherapy (NAC) in patients with breast cancer (BC) compared to the use of MRI (Magnetic Resonance Imaging) alone.

We searched numerous databases, including PubMed, Scopus, Embase, and Science Direct, using curated keywords. The variance of each study was determined using the binomial distribution, and STATA version 14 was used to analyze the data by performing random-effect models. Additionally, we calculated study heterogeneity using the chi-squared test and I² index and utilized funnel plots and Egger tests to assess publication bias.

The current investigation analyzed 239 patients from six published studies. The pooled estimated sensitivity and specificity of ¹⁸F-FDG PET/MRI was 0.91 (95% CI = 0.90 to 0.92, I² = 100% and P = 0.000) and 0.62 (95% CI = 0.53 to 0.72, I² = 99.8% and P = 0.000), respectively. Pooled sensitivity and specificity of MRI were 0.78 (95%CI = 0.59 to 0.96, I² = 100% and P = 0.000) and 0.56 (95%CI = 0.33 to 0.80, I² = 99.8% and P = 0.000), respectively.

Based on our findings, the combined form of ¹⁸F-FDG PET/MRI imaging is more sensitive and specific than MRI alone for predicting response to NAC in BC patients.