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

Purpose: To evaluate the potential of CT texture analysis parameters and metabolic characteristics of melanoma metastases in F- 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 F-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 F-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 SUV (rho -0.292, p 0.017). However, no correlation between CT texture analysis, metabolic F-FDG PET parameters and tumour cell mutation could be established.

Conclusion: CT texture parameters cannot replace the diagnostic value of F- FDG PET/CT for metabolic information in melanoma patients. Discrimination between BRAF- and NRAS mutation status was not feasible with CT texture analysis in this exploratory study.