Characterization of liver nodules in patients with chronic liver disease by MRI: performance of the Liver Imaging Reporting and Data System (LI-RADS v.2018) scale and its comparison with the Likert scale.

OBJECTIVES: To evaluate the performance of the LI-RADS v.2018 scale by comparing it with the Likert scale, in the characterization of liver lesions. METHODS: A total of 39 patients with chronic liver disease underwent MR examination for characterization of 44 liver lesions. Images were independently analyzed by two radiologists using the LI-RADS scale and by another two radiologists using the Likert scale. The reference standard used was either histopathological evaluation or a 4-year MRI follow-up. Receiver operating characteristic analysis was performed. RESULTS: The LI-RADS scale obtained an accuracy of 80%, a sensitivity of 72%, a specificity of 93%, a positive predictive value (PPV) of 93% and a negative predictive value (NPV) of 70%, while the Likert scale achieved an accuracy of 79%, a sensitivity of 73%, a specificity of 87%, a PPV of 89% and a NPV of 70%. The area under the curve (AUC) was 85% for the LI-RADS scale and 83% for the Likert scale. The inter-observer agreement was strong (k = 0.89) between the LI-RADS evaluators and moderate (k = 0.69) between the Likert evaluators. CONCLUSIONS: There was no statistically significant difference between the performances of the two scales; nevertheless, we suggest that the LI-RADS scale be used, as it appeared more objective and consistent.

Do DWI and quantitative DCE perfusion MR have a prognostic value in high-grade serous ovarian cancer?

PURPOSE: To evaluate whether perfusion and diffusion parameters from staging MR in ovarian cancer (OC) patients may predict the presence of residual tumor at surgery and the progression-free survival (PFS) in 12 months. MATERIALS AND METHODS: Patients who are from a single institution, candidate for OC to cytoreductive surgery and undergoing MR for staging purposes were included in this study. Inclusion criteria were: preoperative MR including diffusion-weighted imaging (DWI) and perfusion dynamic contrast-enhanced (DCE) sequence; cytoreductive surgery performed within a month from MR; and minimum follow-up of 12 months. Patients' characteristics including the presence of residual tumor at surgery (R0 or R1) and relapse within 12 months from surgery were recorded. DWI parameters included apparent diffusion coefficient (ADC) of the largest ovarian mass (O-ADC) and normalized ovarian ADC as a ratio between ovarian ADC and muscle ADC (M-ADC). DCE quantitative parameters included were descriptors of tumor vascular properties such as forward and backward transfer constants, plasma volume and volume of extracellular space. Statistical analysis was performed, and p values < 0.05 were considered significant. RESULTS: Forty-nine patients were included. M-ADC showed a slightly significant association with the presence of residual tumor at surgery. None of the other functional parameters showed either difference between R0 and R1 patients or association with PFS in the first 12 months. CONCLUSIONS: This preliminary study demonstrated a slightly significant association between normalized ovarian ADC and the presence of residual tumor at surgery. The other perfusion and diffusion parameters were not significant for the endpoints of this study.

Radiomics of high-grade serous ovarian cancer: association between quantitative CT features, residual tumour and disease progression within 12 months.

OBJECTIVES: To determine if radiomic features, alone or combined with clinical data, are associated with residual tumour (RT) at surgery, and predict the risk of disease progression within 12 months (PD12) in ovarian cancer (OC) patients. METHODS: This retrospective study enrolled 101 patients according to the following inclusion parameters: cytoreductive surgery performed at our institution (9 May 2007-23 February 2016), assessment of BRCA mutational status, preoperative CT available. Radiomic features of the ovarian masses were extracted from 3D structures drawn on CT images. A phantom experiment was performed to assess the reproducibility of radiomic features. The final radiomic features included in the analysis (n = 516) were grouped into clusters using a hierarchical clustering procedure. The association of each cluster's representative radiomic feature with RT and PD12 was assessed by chi-square test. Multivariate analysis was performed using logistic regression models. P values < 0.05 were considered significant. RESULTS: Patients with values of F2-Shape/Compactness1 below the median, of F1- GrayLevelCooccurenceMatrix25/0-1InformationMeasureCorr2 below the median and of F1-GrayLevelCooccurenceMatrix25/-333-1InverseVariance above the median showed higher risk of RT (36%, 36% and 35%, respectively, as opposed to 18%, 18% and 18%). Patients with values of F4-GrayLevelRunLengthMatrix25/-333RunPercentage above the median, of F2 shape/Max3DDiameter below the median and F1-GrayLevelCooccurenceMatrix25/45-1InverseVariance above the median showed higher risk of PD12 (22%, 24% and 23%, respectively, as opposed to 6%, 5% and 6%). At multivariate analysis F2-Shape/Max3DDiameter remained significant (odds ratio (95% CI) = 11.86 (1.41-99.88)). To predict PD12, a clinical radiomics model performed better than a base clinical model. CONCLUSION: This study demonstrated significant associations between radiomic features and prognostic factors such as RT and PD12. KEY POINTS: • No residual tumour (RT) at surgery is the most important prognostic factor in OC. • Radiomic features related to mass size, randomness and homogeneity were associated with RT. • Progression of disease within 12 months (PD12) indicates worse prognosis in OC. • A model including clinical and radiomic features performed better than only-clinical model to predict PD12.

Evaluation of deep myometrial invasion in endometrial cancer patients: is dual-energy CT an option?

OBJECTIVES: Assessment of deep (>50%) myometrial invasion by dual-energy CT (DECT) and Trans-Vaginal US (TVUS) in patients with endometrial cancer. METHODS: We retrospectively enrolled patients with endometrial cancer who underwent DECT and TVUS for pre-surgical staging. Three sets of images were evaluated: 70 keV (routine CT images), 50 keV, and iodine-water reconstructions. The gold standard was pathology after surgery. The agreement between the different imaging modalities and the gold standard was estimated. Sensitivity, specificity and accuracy for each imaging modality were evaluated with 95% confidence intervals (CI). RESULTS: Thirty-nine patients were included. Median time from CT and TVUS to surgery was 23 and 18 days, respectively. The best agreement between evaluation of myometrial infiltration and the gold standard was 0.88 (0.72, 1.00) for the 50 keV images; the worst agreement was 0.43 (0.00, 0.88) for the 70 keV images. CT iodine reconstructions and US agreement were comparable. Specificity, sensitivity and accuracy were 0.91, 1.00, 0.94; 0.57, 0.86, 0.71; 0.82, 1.00, 0.87; 0.91, 0.77, 0.86 for 50 keV, 70 keV, iodine reconstructions and ultrasound, respectively. CONCLUSIONS: DECT is a promising tool for assessment of myometrial invasion in endometrial cancer patients, with a special focus on 50 keV images.

CT Radiogenomic Characterization of EGFR, K-RAS, and ALK Mutations in Non-Small Cell Lung Cancer.

OBJECTIVES: To assess the association between CT features and EGFR, ALK, KRAS mutations in non-small cell lung cancer. METHODS: Patients undergoing chest CT and testing for the above gene mutations were included. Qualitative evaluation of CTs included: lobe; lesion diameter; shape; margins; ground-glass opacity; density; cavitation; air bronchogram; pleural thickening; intratumoral necrosis; nodules in tumour lobe; nodules in non-tumour lobes; pleural retraction; location; calcifications; emphysema; fibrosis; pleural contact; pleural effusion. Statistical analysis was performed to assess association of features with each gene mutation. ROC curves for gene mutations were drawn; the corresponding area under the curve was calculated. P-values <0.05 were considered significant. RESULTS: Of 285 patients, 60/280 (21.43 %) were positive for EGFR mutation; 31/270 (11.48 %) for ALK rearrangement; 64/240 (26.67 %) for KRAS mutation. EGFR mutation was associated with air bronchogram, pleural retraction, females, non-smokers, small lesion size, and absence of fibrosis. ALK rearrangements were associated with age and pleural effusion. KRAS mutation was associated with round shape, nodules in non-tumour lobes, and smoking. CONCLUSIONS: This study disclosed associations between CT features and alterations of EGFR (air bronchogram, pleural retraction, small lesion size, absence of fibrosis), ALK (pleural effusion) and KRAS (round lesion shape, nodules in non-tumour lobes). KEY POINTS: Air bronchogram, pleural retraction, small size relate to EGFR mutation in NSCLC. Pleural effusion and younger age relate to ALK mutation. Round lesion shape, nodules in non-tumour lobes relate to KRAS mutation.

Evaluation of diffusion-weighted imaging (DWI) and MR spectroscopy (MRS) as early response biomarkers in cervical cancer patients.

PURPOSE: To prospectively assess whether choline levels and Apparent Diffusion Coefficient (ADC) values within cervical cancers before, during, and after non-surgical therapy are predictive of tumour response. PATIENTS AND METHODS: Patients undergoing MR examination for staging of cervical cancer, candidate for non-surgical therapy, were prospectively enrolled. According to the status at the end of therapies, patients were divided into responders and non-responders. The final outcome after a 5-year follow-up was classified as No Evidence of Disease (NED) or Progression of Disease (PD). Baseline values of mean ADC and Cho/H2O were compared between responders and non-responders, as well as between patients with NED and PD. The percent variation of ADC and Cho/H2O values over time was compared. P values <0.05 were considered significant. RESULTS: 16 patients were included. There was no significant difference at baseline between responders (n = 12) and non-responders (n = 4), nor between NED (n = 11) PD patients (n = 5), in ADC values and Cho/H2O ratio. There was no significant difference in percent variation of ADC values and of Cho/H2O, comparing responders and non-responders. There was a significant increase in absolute values of ADC from the initial to mid-therapy MRI (p = 0.0001), while Cho/H2O was stable (p value: 0.61). In the four non-responders, the ADC increase was not significant (p value: 0.25), while it was significant in the 11 responders (p value: 0.001). Values of spectroscopy were stable in both responders and non-responders. CONCLUSIONS: High increases of ADC values from baseline to mid-therapy MR reflect response to therapies. There were no significant variations in choline/water ratios over time.

Plaster cast treatment for distal forearm fractures in children: which index best predicts the loss of reduction?

Several radiological indices were introduced to evaluate cast adequacy for paediatric distal forearm fractures: cast, gap, padding, Canterbury (reflecting the cast shape and the amount of padding) and three-point indices, and second metacarpal-radius angle (measuring cast ulnar-moulding). The aim of this study is to define which index is most reliable in assessing cast adequacy and predicting redisplacements. Hundred twenty-four consecutive patients (age 5-18) affected by distal both-bone forearm or radius fractures treated with casting were included. These indices and the displacement angles were calculated on the initial radiograph after reduction. Radiographs at 7 and 30 days were taken to assess if the loss of reduction occurred, and measure the displacement deltas (displacement angle at day 30 - displacement angle at day 0). Student's t-test, Chi-square test and Pearson's correlation were used for the statistical analysis. High padding (P = 0.034), Canterbury (P = 0.002) and Cast (P < 0.001) indices showed an association with redisplacements in distal forearm fractures. Both-bone forearm fractures have a higher risk of loss of reduction than radius fractures [odds ratio (OR = 4.99, 95% confidence interval (CI) = 2.21-11.3, P < 0.001]. A higher displacement delta in antero-posterior (Pearson's r = 0.418, P = 0.037) and lateral (P = 0.045) views for both-bone fractures showed an association with a high gap Index. Regarding radius fractures, a high cast index is associated with a higher displacement delta in antero-posterior (P = 0.035). The three-point index and the second metacarpal-radius angle did not show any association with the redisplacement risk. Cast oval moulding without excessive padding may prevent redisplacements in paediatric distal forearm fractures, while casts ulnar-moulding does not.

Pre-operative evaluation of epithelial ovarian cancer patients: Role of whole body diffusion weighted imaging MR and CT scans in the selection of patients suitable for primary debulking surgery. A single-centre study.

PURPOSE: to evaluate the accuracy of Whole Body MRI including Diffusion-Weighted Imaging sequences (WB DWI MR) in the assessment of sites of disease in epithelial ovarian cancer (EOC), in comparison to CT; to evaluate whether a clinical-radiological score may predict suboptimal cytoreductive surgery. METHODS: patients with suspected EOC who underwent pre-operative WB DWI MR were included; CT scans were recorded. Data recorded included: age, staging, dates of examinations and surgery; tumour markers; sites of disease at imaging scans and at surgery. For calculation of sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of WB DWI MR and CT, surgical evaluation represented the gold standard. The accuracy of WB DWI MR and CT was compared. The association between clinical and radiological criteria with sub-optimal cytoreduction was tested to identify a final model to predict sub-optimal cytoreduction. RESULTS: 92 patients were included; 77/92 (83.7 %) were optimally cytoreduced. Sixty-six CT and 92 MR examinations were evaluated. WB DWI MR showed overall higher accuracy than CT in assessing all sites, but it performed significantly better than CT specifically for involvement of mesentery, lumbo-aortic lymph nodes, pelvis, large bowel, sigmoid-rectum. The predicting score for suboptimal cytoreduction included: mesenteric carcinomatosis; mesenteric retraction; large bowel carcinomatosis. CONCLUSIONS: In pre-operative evaluation of EOC patients, WB DW MRI is accurate for assessment of multiple sites and it is significantly more accurate than CT for specific unresectable sites. In our series, significant sites of disease for suboptimal cytoreduction were mesenteric carcinomatosis, mesenteric retraction and large bowel carcinomatosis.

Endometrial cancer: an overview of novelties in treatment and related imaging keypoints for local staging.

Endometrial cancer is the most common gynaecologic malignancy in developed countries and its incidence is increasing. First-level treatment, if no contraindicated, is based on surgery. Pre-operative imaging is needed for evaluation of local extent and detection of distant metastases in order to guide treatment planning. Radiological evaluation, based on transvaginal ultrasound, MR and CT, can make the difference in disease management, paying special attention to assessment of entity of myometrial invasion, cervical stromal extension, and assessment of lymph nodal involvement and distant metastases.