CT texture analysis compared to Positron Emission Tomography (PET) and mutational status in resected melanoma metastases

Abstract Purpose To evaluate the potential of CT texture analysis parameters and metabolic characteristics of melanoma metastases in 18F- FDG PET/CT to predict relevant mutations of tumour cells for targeted therapy in metastatic melanoma patients in correlation with histopathologic specimen. Material and methods 66 melanoma patients, examined with contrast-enhanced 18F-FDG PET/CT before scheduled metastasectomy without any prior systemic therapy, were included in this single-centre retrospective analysis under IRB waiver. The largest, resected metastasis in each patient was assessed with CT texture analysis and semiquantitative 18F-FDG PET parameters. Correlation between imaging parameters and histopathological mutations (BRAF- and NRAS- genes) were calculated. Results Attenuation standard deviation (SD) within target lesion indicated a weak correlation with its SUVpeak (rho −0.292, p 0.017). However, no correlation between CT texture analysis, metabolic 18F-FDG PET parameters and tumour cell mutation could be established. Conclusion CT texture parameters cannot replace the diagnostic value of 18F- FDG PET/CT for metabolic information in melanoma patients. Discrimination between BRAF- and NRAS mutation status was neither feasible with CT texture analysis nor 18F-FDG PET in this exploratory study.