Comparisons between glucose analogue 2-deoxy-2-(^(18)F)fluoro-D-glucose and ^(18)F-sodium fluoride positron emission tomography/computed tomography in breast cancer patients with bone lesions

AIM: To compare 2-deoxy-2-(^(18)F)fluoro-D-glucose(^(18)FFDG) and ^(18)F-sodium(^(18)F-NaF) positron emission tomography/computed tomography(PET/CT) accuracy in breast cancer patients with clinically/radiologically suspected or known bone metastases.METHODS: A total of 45 consecutive patients with breast cancer and the presence or clinical/biochemical or radiological suspicion of bone metastatic disease underwent ^(18)F-FDG and ^(18)F-fluoride PET/CT. Imaging results were compared with histopathology when available, or clinical and radiological follow-up of at least 1 year. For each technique we calculated: Sensitivity(Se), specificity(Sp), overall accuracy, positive and negative predictive values, error rate, and Youden's index. Mc Nemar's χ~2 test was used to test the difference in sensitivity and specificity between the two diagnostic methods. All analyses were computed on a patient basis, and then on a lesion basis, with consideration ofthe density of independent lesions on the coregistered CT(sclerotic, lytic, mixed, no-lesions) and the divergent site of disease(skull, spine, ribs, extremities, pelvis). The impact of adding ^(18)F-Na F PET/CT to the work-up of patients was also measured in terms of change in their management due to ^(18)F-Na F PET/CT findings. RESULTS: The two imaging methods of ^(18)F-FDG and ^(18)F-fluoride PET/CT were significantly different at the patient-based analysis: Accuracy was 86.7% and 84.4%, respectively(Mc Nemar's χ~2 = 6.23, df = 1, P = 0.01). Overall, 244 bone lesions were detected in our analysis. The overall accuracy of the two methods was significantly different at lesion-based analysis(Mc Nemar's χ~2 = 93.4, df = 1, P < 0.0001). In the lesion density-based and site-based analysis, ^(18)F-FDG PET/CT provided more accurate results in the detection of CT-negative metastasis(P < 0.002) and vertebral localizations(P < 0.002); ^(18)F-Na F PET/CT was more accurate in detecting sclerotic(P < 0.005) and rib lesions(P < 0.04). ^(18)F-Na F PET/CT led to a change of management in 3 of the 45 patients(6.6%) by revealing findings that were not detected at ^(18)F-FDG PET/CT. CONCLUSION: ^(18)F-FDG PET/CT is a reliable imaging tool in the detection of bone metastasis in most cases, with a diagnostic accuracy that is slightly, but significantly, superior to that of ^(18)F-Na F PET/CT in the general population of breast cancer patients. However, the extremely high sensitivity of ^(18)F-fluoride PET/CT can exploit its diagnostic potential in specific clinical settings(i.e., small CT-evident sclerotic lesions, high clinical suspicious of relapse, and negative ^(18)F-FDG PET and conventional imaging).

Correlation between thoracic aorta 18F-natrium fluoride uptake and cardiovascular risk

AIM: To investigating the relationship between thoracic and cardiac 18F-Natrium-Fluoride(18F-Na F) uptake,as a marker of ongoing calcification and cardiovascular risk factors.METHODS: Seventy-eight patients(44 females,mean age 63,range 44-83) underwent whole body 18F-Na F positron emission tomography/computed tomography. Cardiovascular risk(CVR) was used to divide these patients in three categories: Low(LR),medium(MR) and high risk(HR). 18F-Na F uptake was measured by manually drawing volumes of interest on the ascendingaorta,on the aortic arch,on the descending aorta and on the myocardium; average standardized uptake value was normalized for blood-pool,to obtain target-tobackground ratio(TBR). Values from the three aortic segments were then averaged to obtain an index of the whole thoracic aorta.RESULTS: A significant difference in whole thoracic aorta TBR was detected between HR and LR(1.84 ± 0.76 vs 1.07 ± 0.3,P < 0.001),but also between MR and HR-LR(1.4 ± 0.4,P < 0.02 and P < 0.01,respectively). Significance of this TBR stratification strongly varied among thoracic aorta subsegments and the lowest P values were reached in the descending aorta(P < 0.01). Myocardial uptake provided an effective CVR classes stratification(P < 0.001).Correlation between TBR and CVR was appreciable when the whole thoracic aorta was considered(R = 0.67),but it peaked when correlating the descending thoracic segment(R = 0.75),in comparison with the aortic arch and the ascending segment(R = 0.55 and 0.53,respectively). CONCLUSION: Fluoride uptake within the thoracic aorta wall effectively depicts patients' risk class and correlates with cardiovascular risk. Descending aorta is the most effective in CVR determination.

Is precision medicine for colorectal liver metastases still a utopia?New perspectives by modern biomarkers,radiomics,and artificial intelligence

The management of patients with liver metastases from colorectal cancer is still debated.Several therapeutic options and treatment strategies are available for an extremely heterogeneous clinical scenario.Adequate prediction of patients’outcomes and of the effectiveness of chemotherapy and loco-regional treatments are crucial to reach a precision medicine approach.This has been an unmet need for a long time,but recent studies have opened new perspectives.New morphological biomarkers have been identified.The dynamic evaluation of the metastases across a time interval,with or without chemotherapy,provided a reliable assessment of the tumor biology.Genetics have been explored and,thanks to their strong association with prognosis,have the potential to drive treatment planning.The liver-tumor interface has been identified as one of the main determinants of tumor progression,and its components,in particular the immune infiltrate,are the focus of major research.Image mining and analyses provided new insights on tumor biology and are expected to have a relevant impact on clinical practice.Artificial intelligence is a further step forward.The present paper depicts the evolution of clinical decision-making for patients affected by colorectal liver metastases,facing modern biomarkers and innovative opportunities that will characterize the evolution of clinical research and practice in the next few years.