Pretreatment 18F-FDG PET/CT Imaging Predicts the KRAS/NRAS/BRAF Gene Mutational Status in Colorectal Cancer

Abstract

Objective. To investigate the association between KRAS/NRAS/BRAF mutations and metabolic parameters of pretreatment 18F-FDG PET/CT in colorectal cancer (CRC). Methods. A total of 85 patients with CRC were included in the study. PET/CT was performed in all the patients before surgery. The histopathological examination and analysis of the gene mutational status of the primary tumor were conducted. The associations among clinical features, PET metabolic parameters, and the gene mutational status were investigated. Moreover, receiver operating characteristic (ROC) curves for maximum standard uptake value (SUVmax) of the primary tumor were generated along with analysis of the target tissue to nontarget tissue ratio (T/NT) for predicting the efficacy of KRAS/NRAS/BRAF mutations in CRC. Finally, the corresponding area under the curve, the optimal cutoff value, and the corresponding sensitivity and specificity were obtained. Results. The mutation rate of KRAS/NRAS/BRAF was 54.12% (46/85). In addition, both SUVmax and T/NT were significantly higher in the KRAS/NRAS/BRAF-mutation groups compared to the wild-type group (15.88 ± 6.71 vs. 12.59 ± 5.79, 8.04 ± 3.03 vs. 6.38 ± 2.80; P = 0.012 and 0.004, respectively). Results from the ROC curve also showed that the cutoff values for T/NT and SUVmax were 5.14 and 12.40, respectively, while the predictive accuracy was 0.682 and 0.647, respectively. On the other hand, the sensitivity was 91.30% and 65.22% while the specificity was 43.59% and 64.10%, respectively. Moreover, univariate analysis showed that the KRAS/NRAS/BRAF mutation was not significantly associated with gender, age, lesion location, tumor length, pathological type, tissue differentiation, and UICC staging (all P > 0.05 ). Conclusion. T/NT ratio and SUVmax could be the potential surrogate imaging indicators to predict the KRAS/NRAS/BRAF mutational status in CRC patients.

Sarcopenia and Myosteatosis Are Associated with Neutrophil to Lymphocyte Ratio but Not Glasgow Prognostic Score in Colorectal Cancer Patients

“…Mutant KRAS also upregulates expression of the GLUT1 glucose transporter, promoting glucose uptake by cells. Interestingly, several studies have demonstrated higher glucose accumulation in 18F-FDG PET/CT scans in CRCs with KRAS/NRAS/BRAF mutations [48]. The association between myosteatosis and serrated morphology suggests that serrated CRC patients might have an increased risk of myosteatosis, and we hypothesize that this may reflect higher glucose metabolism in serrated CRC.…”

Predictive value of intratumoral-metabolic heterogeneity derived from 18F-FDG PET/CT in distinguishing microsatellite instability status of colorectal carcinoma

“…PET/CT is a systemic examination that can detect the distant metastasis of tumors. In recent years, 18 F-FDG PET/CT has demonstrated efficiency in staging, predicting prognosis, assessing treatment response, and determining gene mutational status in patients with CRC ( 14 – 17 ). MSI-H CRCs have higher intratumoral heterogeneity compared with microsatellite stability (MSS) CRCs ( 9 , 12 , 13 , 18 ).…”

Utility and specificity of plasma heat shock protein 90 alpha, CEA, and CA199 as the diagnostic test in colorectal cancer liver metastasis

“…Paraffin-embedded sections were used to extract deoxyribonucleic acid, and real-time fluorescent quantitative polymerase chain reaction technology was employed for amplification detection. Next-generation sequencing (NGS) was used to analyze 17 mutations in the Kirsten rat sarcoma 2 viral oncogene homolog (KRAS) gene (exons 2, 3, and 4), 13 mutations in the neuroblastoma rat sarcoma viral oncogene homolog (NRAS) gene (exons 2, 3, and 4), and 1 mutation in the v-raf murine sarcoma viral oncogene homolog B1 (BRAF) gene (exon 15: V600 E) ( 15 ).…”