Texture analysis of 18F-FDG PET/CT and CECT: Prediction of refractoriness of Hodgkin lymphoma with mediastinal bulk involvement.

To recognize patients at high risk of refractory disease, the identification of novel prognostic parameters improving stratification of newly diagnosed Hodgkin Lymphoma (HL) is still needed. This study investigates the potential value of metabolic and texture features, extracted from baseline 18F-FDG Positron Emission Tomography/Computed Tomography (PET) and Contrast-Enhanced Computed Tomography scan (CECT), together with clinical data, in predicting first-line therapy refractoriness (R) of classical HL (cHL) with mediastinal bulk involvement. We reviewed 69 cHL patients who underwent staging PET and CECT. Lesion segmentation and texture parameter extraction were performed using the freeware software LIFEx 6.3. The prognostic significance of clinical and imaging features was evaluated in relation to the development of refractory disease. Receiver operating characteristic curve, Cox proportional hazard regression and Kaplan-Meier analyses were performed to examine the potential independent predictors and to evaluate their prognostic value. Among clinical characteristics, only stage according to the German Hodgkin Group (GHSG) classification system significantly differed between R and not-R. Among CECT variables, only parameters derived from second order matrices (gray-level co-occurrence matrix (GLCM) and gray-level run length matrix (GLRLM) demonstrated significant prognostic power. Among PET variables, SUVmean, several variables derived from first (histograms, shape), and second order analyses (GLCM, GLRLM, NGLDM) exhibited significant predictive power. Such variables obtained accuracies greater than 70% at receiver operating characteristic analysis and their PFS curves resulted statistically significant in predicting refractoriness. At multivariate analysis, only HISTO_EntropyPET extracted from PET (HISTO_EntropyPET ) and GHSG stage resulted as significant independent predictors. Their combination identified 4 patient groups with significantly different PFS curves, with worst prognosis in patients with higher HISTO_EntropyPET values, regardless of the stage. Imaging radiomics may provide a reference for prognostic evaluation of patients with mediastinal bulky cHL. The best prognostic value in the prediction of R versus not-R disease was reached by combining HISTO_EntropyPET with GHSG stage.

Magnetic resonance imaging in naso-oropharyngeal carcinoma: role of texture analysis in the assessment of response to radiochemotherapy, a preliminary study.

OBJECTIVE: Identifying MRI texture parameters able to distinguish inflammation, fibrosis, and residual cancer in patients with naso-oropharynx carcinoma after radiochemotherapy (RT-CHT). MATERIAL AND METHODS: In this single-centre, observational, retrospective study, texture analysis was performed on ADC maps and post-gadolinium T1 images of patients with histological diagnosis of naso-oropharyngeal carcinoma treated with RT-CHT. An initial cohort of 99 patients was selected; 57 of them were later excluded. The final cohort of 42 patients was divided into 3 groups (inflammation, fibrosis, and residual cancer) according to MRI, 18F-FDG-PET/CT performed 3-4 months after RT-CHT, and biopsy. Pre-RT-CHT lesions and the corresponding anatomic area post-RT-CHT were segmented with 3D slicer software from which 107 textural features were derived. T-Student and Wilcoxon signed-rank tests were performed, and features with p-value < 0.01 were considered statistically significant. Cut-off values-obtained by ROC curves-to discriminate post-RT-CHT non-tumoural changes from residual cancer were calculated for the parameters statistically associated to the diseased status at follow-up. RESULTS: Two features-Energy and Grey Level Non-Uniformity-were statistically significant on T1 images in the comparison between 'positive' (residual cancer) and 'negative' patients (inflammation and fibrosis). Energy was also found to be statistically significant in both patients with fibrosis and residual cancer. Grey Level Non-Uniformity was significant in the differentiation between residual cancer and inflammation. Five features were statistically significant on ADC maps in the differentiation between 'positive' and 'negative' patients. The reduction in values of such features between pre- and post-RT-CHT was correlated with a good response to therapy. CONCLUSIONS: Texture analysis on post-gadolinium T1 images and ADC maps can differentiate residual cancer from fibrosis and inflammation in early follow-up of naso-oropharyngeal carcinoma treated with RT-CHT.

Imaging biomarkers in the diagnosis of salivary gland tumors: the value of lesion/parenchyma ratio of perfusion-MR pharmacokinetic parameters.

BACKGROUND AND PURPOSE: Morphologic magnetic resonance imaging (MRI) for characterization of salivary gland tumors has limited utility, and the use of perfusion MRI data in the clinical setting is controversial. We examined the potential of tissue-normalized dynamic contrast-enhanced (DCE) MRI pharmacokinetic parameters of salivary gland tumors as imaging biomarkers for characterization and differentiation between benign and malignant lesions. MATERIALS AND METHODS: DCE-MR images acquired from 60 patients with parotid and submandibular gland tumors were retrospectively reviewed. Pharmacokinetic parameters as transfer constant (Ktrans), rate constant (Kep), extracellular space volume (Ve), fractional plasma volume (Vp), and AEC (area of all times enhancement curve) were measured on both the lesion and the normal contralateral salivary gland parenchyma. Lesion/parenchyma ratio (L/P) for each parameter was calculated. RESULTS: Five groups of lesions were identified (reference: histopathology): pleomorphic adenomas(n = 20), Warthin tumors(n = 16), other benign entities(n = 4), non-Hodgkin lymphomas(n = 4), and malignancies(n = 16). Significant differences were seen for mean values of L/PKtrans (higher in malignancies), L/PKep (lower in adenomas than Warthin tumors), L/PVe (lower in Warthin tumors and lymphomas), L/PVp (higher in Warthin tumors and malignancies than adenomas), and L/PAEC (higher in malignancies). Significant differences were found between benign and malignant (non-lymphoproliferative) lesions in mean value of L/PKtrans (0.485 and 1.581), L/PVp (1.288 and 2.834), and L/PAEC (0.682 and 1.910). ROC analysis demonstrated the highest AUC (0.96) for L/PAEC, with sensitivity and specificity for malignancy of 93.8% and 97.5% (cutoff value = 1.038). CONCLUSION: Lesion/parenchyma ratio of DCE-MRI pharmacokinetic data could be helpful for recognizing the principal types of salivary gland tumors; L/PAEC seems a valuable biomarker for differentiating benign from malignant tumors.

Electronic processing of digital panoramic radiography for the detection of apical periodontitis.

INTRODUCTION: This study aimed to evaluate the accuracy of both digital complete and small portion of panoramic radiography (PAN) in the detection of clinically/surgically confirmed asymptomatic apical periodontitis (AP) lesions with and without endodontic treatment. METHODS: A total of 480 patients/teeth including 120 AP with and without endodontic treatment, and 120 healthy periapex with and without endodontic treatment were detected via CBCT using the periapical index system. Each diseased and healthy patient underwent PAN first and a CBCT scan within 40 days. All 480 cases were assessed by four different methods, as follows: complete PAN with clinical examination of each tooth available and not available, respectively, and small portion of PAN in which a root with crown and root without crown were displayed, respectively. Periapical index system was also used to assess AP by PAN. Accuracy for both complete and small portion of PAN with respect to CBCT was analyzed. RESULTS: The overall accuracy of the four methods for teeth with endodontic treatment (73.4) was higher than teeth without endodontic treatment (66.6). Accuracy of complete PAN and portion of PAN was 71.3 and 68.7, respectively. As regards teeth without endodontic treatment, accuracy was higher for complete PAN in the upper/lower incisive area and for small portion of PAN in the upper molar area. No difference was found in teeth with endodontic treatment. CONCLUSION: Complete and small portion of PAN showed greater accuracy in the upper/lower incisive area and upper molar area of untreated teeth, respectively, whereas no difference was found in treated teeth.

Diagnostic imaging of typical lung carcinoids: relationship between MDCT, 111In-Octreoscan and 18F-FDG-PET imaging features with Ki-67 index.

AIMS: This study analyses the capability of contrast-enhanced multi-detector computed tomography (MDCT) and spectrum of molecular imaging to characterize typical carcinoids (TCs) of lung and their relationship with Ki-67 index. MATERIALS AND METHODS: We analysed 68 patients with histological diagnosis of pulmonary TC, which underwent both MDCT and nuclear molecular imaging (somatostatin receptor scintigraphy/SPECT with 111In-pentetreotide and 18F-FDG-PET/CT) at staging evaluation before surgery. The MDCT scan was reviewed for the following features: size, margins, contrast enhancement, presence of calcifications, bronchial obstruction, lymph nodes and metastases. In 111In-pentetreotide SPECT, tumour/non-tumour ratio was measured at 4- and 24-h post-injection and the per cent difference was calculated (T/NT%). FDG uptake was measured as the ratio between lesion SUVmax and liver SUVmean (SUV ratio). All imaging features were correlated between them and with Ki-67 index. RESULTS: Forty-four of the 68 lesions (65%) were in the right lung. In MDCT, scan lesions appeared as a well-defined nodule in 44 patients (65%) and irregular mass in 24 patients (35%). Contrast intense enhancement was present in 53 patients (78%), calcifications in 20 patients (29%) and bronchial obstruction in 24 patients (35%). Lymph nodes and metastasis were present in 13 (19%) and 15 (22%) patients. Ki-67 index was negatively correlated with T/NT% and positively with SUV ratio; T/NT% and SUV ratio were inversely correlated. The presence of irregular margins and metastases was negatively related to T/NT%. The presence of a mass, irregular margins, bronchial obstruction, lymph nodes and metastasis was positively related to higher SUV ratio. The presence of irregular margins, bronchial obstruction, lymph nodes and metastases was significantly correlated with a higher grade of Ki-67 index. CONCLUSIONS: MDCT and nuclear molecular imaging are important to characterize lung TCs. The majority of TCs appear as a well-defined nodule generally not associated with extra-thorax signs. We found a significant correlation between some MDCT aspects, nuclear medicine features and Ki-67 index. The association of MDCT and nuclear medicine imaging may be useful in predicting proliferative activity and prognosis of lung TCs.

The role of diffusion-weighted and dynamic contrast enhancement perfusion-weighted imaging in the evaluation of salivary glands neoplasms.

OBJECTIVES: To evaluate the association of magnetic resonance diffusion-weighted imaging (DwI) and dynamic contrast-enhanced perfusion-weighted imaging (DCE-PwI) with a temporal resolution of 5 s, wash-in < 120 s, and wash-out ratio > 30% in the evaluation of salivary glands neoplasms. METHODS: DwI and DCE-PwI of 92 salivary glands neoplasms were assessed. The apparent diffusion coefficient (ADC) was calculated by drawing three regions of interest with an average area of 0.30-0.40 cm2 on three contiguous axial sections. The time/intensity curve was generated from DCE-PwI images by drawing a region of interest that included at least 50% of the largest lesion section. Vessels, calcifications, and necrotic/haemorrhagic or cystic areas within solid components were excluded. The association of ADC ≥ 1.4 × 10-3 mm2/s with type A curves (progressive wash-in) and ADC 0.9-1.4 × 10-3 mm2/s with type C curves (rapid wash-in/slow wash-out) were tested as parameters of benignity and malignancy, respectively. Type B curve (rapid wash-in/rapid wash-out) was not used as a reference parameter. RESULTS: ADC ≥ 1.4 × 10-3 mm2/s and type A curves were observed only in benign neoplasms. ADC of 0.9-1.4 × 10-3 mm2/s and type C curves association showed specificity of 94.9% and positive predictive value of 81.8% for epithelial malignancies. The association of ADC < 0.9 × 10-3 mm2/s with type B and C curves showed diagnostic accuracy of 94.6% and 100% for Warthin tumour and lymphoma, respectively. CONCLUSIONS: ADC ≥ 1.4 × 10-3 mm2/s and type A curves association was indicative of benignity. Lymphomas exhibited ADC < 0.7 × 10-3 mm2/s and type C curves. The association of ADC < 0.9 × 10-3 mm2/s and type B and C curves had accuracy 94.6% and 88.5% for Warthin tumour and epithelial malignancies, respectively.

Current role of computed tomography imaging in the evaluation of cartilage invasion by laryngeal carcinoma.

OBJECTIVES: To evaluate thyroid, arytenoid, and cricoid cartilage invasion on computed tomography (CT) imaging in patients undergoing total laryngectomy for both primary and recurrent laryngeal carcinoma. Secondary endpoint was to compare laryngeal cartilage invasion between primary and recurrent tumours. METHODS: Pre-treatment CT of 40 patients who had undergone total laryngectomy was retrospectively evaluated and compared with histology. Focal erosions of thyroid cartilage were accounted for neoplastic invasion of the inner cortex. Full-thickness thyroid cartilage invasion was defined as a tumour-like tissue replacing thyroid cartilage or extended in extra-laryngeal soft tissues. Sclerosis and erosion of arytenoid and cricoid cartilages were assessed as signs of neoplastic invasion. RESULTS: CT erosion showed perfect agreement for thyroid inner cortex and cricoid cartilage invasion and almost perfect agreement (87%) for arytenoid cartilage invasion. For tumours in contact with thyroid cartilages, the absence of CT erosion underestimated inner cortex infiltration. CT showed perfect agreement in predicting full-thickness thyroid cartilage invasion only in the case of extra-laryngeal neoplastic extension. Arytenoid sclerosis showed poor correlation with neoplastic invasion. For primary tumours, CT demonstrated good (inner cortex 75%; full-thickness 85%), substantial (67.5%), and perfect (100%) accuracy in thyroid, arytenoid, and cricoid cartilage invasion, respectively. No CT differences were observed between primary and recurrent laryngeal tumours. CONCLUSION: Tumour-like tissue extension in the extra-laryngeal soft tissues was accurate in predicting thyroid cartilage full-thickness invasion. Erosions of arytenoid, cricoid, and thyroid cartilages' inner cortex on CT were highly indicative of neoplastic infiltration. No CT difference in cartilage infiltration between primary and recurrent tumours was observed.

Primary pulmonary lymphoma: imaging findings in 30 cases.

PURPOSE: To present our experience of cases of primary pulmonary lymphoma (PPL) found between January 2002 and July 2018, focusing on the radiological features and the differential diagnosis in order to contribute to the difficult role of the radiologist in the disease identification and to help the clinicians to reach the diagnosis. MATERIALS AND METHODS: CT scans of 30 patients (14 men and 16 women, aged 58-86, mean age 72 years) with PPL were retrospectively reviewed. All patients had a histopathological confirmation of the disease: MALT lymphoma (23 patients, 76.6%); diffuse large B-cell lymphoma-DLBCL (seven patients, 23.4%). All the staging CT scans were evaluated by three experienced radiologists dedicated to thoracic disease in order to radiologically define the predominant pattern of presentation. RESULTS: The following parenchymal patterns were observed: 11 patients with single/multiple nodules, five with masses/mass-like consolidations, 14 with consolidations with air bronchogram, 16 with ground-glass opacity, ten with angiogram sign, 22 with perilymphatic and/or peribronchovascular spread, 15 with associated lymphadenopathies, and 13 with pleural/chest wall involvement. The main characteristics of PPLs were the presence of consolidations and ground-glass opacities, with perilymphatic and/or bronchovascular spread. CONCLUSION: All the characteristics of the work should alert the radiologist to consider lymphoma among the possible differential diagnoses, always correlating the results of the CT examination with appropriate clinical laboratory evaluations.

CT assessment of tumor heterogeneity and the potential for the prediction of human papillomavirus status in oropharyngeal squamous cell carcinoma.

The aim of this study is to find a correlation between tumoral heterogeneity of squamous cell carcinoma of the oropharynx and human papillomavirus (HPV) status and to determine whether analysis of texture features of primary lesion on contrast-enhanced CT (CECT) images can be useful in predicting the HPV positivity. Fifty patients with diagnosis of oropharyngeal carcinoma and pre-treatment CECT were included; tumoral heterogeneity of each lesion was evaluated by extracting quantitative texture parameters of first and higher orders. T test and logistic regression were conducted to evaluate the effects of different textural characteristics. There were 35 HPV+ and 15 HPV- lesions. Statistically significant (p < 0.05) differences were seen in multiple higher-order extracted parameters. The logistic regression model correctly classified lesions with an accuracy of 95.2%. CT texture analysis of primary oropharyngeal cancer may be used as a tool for predicting the HPV status.

Effectiveness of a social inclusion program in people with non-affective psychosis.

BACKGROUND: People with psychotic illness suffer from reduced quality of life and often from an insufficient level of social inclusion. These variables are associated with several negative outcomes, such as higher neuro-cognitive deficits, negative symptoms, internalised stigma, increased cardiovascular risk and, most importantly, excess mortality. To date, only a minority of social interventions in psychosis have been investigated. Since 2011, the Department of Mental Health and Substance Abuse in Modena introduced the "Social Point" program, which provides social inclusion interventions to promote active social participation for patients suffering from severe mental illness. The aim of this study was to assess whether a social inclusion intervention is associated with better outcomes in terms of personal and social recovery, with particular reference to the areas of social functioning and activity, and subjective dimensions such as self-esteem, self-stigma and perceived quality of life. METHODS: A cross-sectional design was adopted to compare 30 subjects, selected at the completion of "Social Point" program, with a group of subjects, matched for socio-demographic and clinical features, selected from a wait list for "Social Point". All subjects were evaluated by means of instruments assessing: level of disability, level of functioning, severity of psychopathology, self-esteem, internalised stigma and quality of life. RESULTS: Overall, the results of the study suggest that social inclusion interventions may be effective in people suffering from non-affective psychosis. A dose-effect relationship was also found between higher number of activities per patient and better outcomes within both social and psychopathological domains. However, due to the cross-sectional design of the study no definitive causality can be inferred. CONCLUSION: Psychosocial interventions promoting social inclusion are likely to represent an effective approach to improve personal and social recovery.

Excess mortality in people with mental illness: findings from a Northern Italy psychiatric case register.

PURPOSE: People with mental disorders show mortality rates up to 22.2 times higher than that of the general population. In spite of progressive increase in life expectancy observed in the general population, the mortality gap of people suffering from mental health problems has gradually widened. The aim of this paper was to study mortality rates in people suffering from mental illness in a cohort of people (16,981 subjects) in the local mental health register of the province of Modena during the decade 2006-2015. METHODS: Standardized Mortality Ratios (SMRs) were calculated to compare the mortality of people with mental disorders to the mortality of people living in the province of Modena and the excess of mortality was studied in relation to the following variables: gender, age group, diagnosis and causes of death. In addition, Poisson regression analysis was performed to study the association between patient characteristics and mortality. RESULTS: An overall excess mortality of 80% was found in subjects under the care of mental health services as compared to the reference population (SMR = 1.8, 95% CI 1.7-1.9). Subjects in the 15-44 year group presented the highest SMR (9.2, 95% CI 6.9-11.4). The most prevalent cause of death was cancer (28.1% of deaths). At the Poisson regression, the diagnosis "Substance abuse and dependence" showed the highest relative risk (RR) (4.00). Moreover, being male, single, unemployed and with a lower qualification was associated with higher RRs. CONCLUSIONS: Our study confirms that subjects with mental illness have higher SMR. Noteworthy, the overall higher risk of mortality was observed in the younger age group.

Diagnostic imaging to detect and evaluate response to therapy in bone metastases from prostate cancer: current modalities and new horizons.

Different therapeutic options for the management of prostate cancer (PC) have been developed, and some are successful in providing crucial improvement in both survival and quality of life, especially in patients with metastatic castration-resistant PC. In this scenario, diverse combinations of radiopharmaceuticals (for targeting bone, cancer cells and receptors) and nuclear medicine modalities (e.g. bone scan, SPECT, SPECT/CT, PET and PET/CT) are now available for imaging bone metastases. Some radiopharmaceuticals are approved, currently available and used in the routine clinical setting, while others are not registered and are still under evaluation, and should therefore be considered experimental. On the other hand, radiologists have other tools, in addition to CT, that can better visualize bone localization and medullary involvement, such as multimodal MRI. In this review, the authors provide an overview of current management of advanced PC and discuss the choice of diagnostic modality for the detection of metastatic skeletal lesions in different phases of the disease. In addition to detection of bone metastases, the evaluation of response to therapy is another critical issue, since it remains one of the most important open questions that a multidisciplinary team faces when optimizing the management of PC. The authors emphasize the role of nuclear modalities that can presently be used in clinical practice, and also look at future perspectives based on relevant clinical data with novel radiopharmaceuticals.

Diffusion-weighted magnetic resonance imaging in the prediction and assessment of chemotherapy outcome in liver metastases.

PURPOSE: This study assessed the capability of magnetic resonance (MR) diffusion-weighted imaging (DwI) with measurement of apparent diffusion coefficient (ADC) in both predicting and evaluating the response to chemotherapy (CHT) of liver metastases by itself and along with preliminary dimensional assessment. METHODS AND MATERIALS: Patients affected by liver metastases from cancers of the digestive tract and breast were prospectively enrolled and underwent computed tomography and MR-DwI before CHT (time 0) and 20-25 days after the beginning of the second cycle (time 3). Moreover, MR-DwI was performed 10-15 (time 1) and 20-25 days (time 2) after the beginning of the first cycle. Maximum diameter and mean ADC value (×10(-3) mm(2)/s) of metastases were evaluated. Lesions were classified as progressive disease (PD), stable disease (SD) or partial response (PR) according to dimensional changes between time 0 and time 3, following RECIST 1.1 indications. Clinically, PD lesions were defined as nonresponding (NR), and SD and PR lesions as responding (R). Analysis of variance and ROC analyses were performed (significance at p < 0.05). RESULTS: Eighty-six metastases (33 patients) were classified as follows: 15 PD, 39 SD and 32 PR without significant differences in mean ADC values among the groups before CHT and at all corresponding times. The mean ADC values of SD and PR groups at times 1 (respectively 1.66 ± 0.36 and 1.59 ± 0.23), 2 (1.72 ± 0.42 and 1.68 ± 0.37) and 3 (1.86 ± 0.44 and 1.73 ± 0.39) were significantly higher than the corresponding values at time 0 (1.50 ± 0.30 and 1.39 ± 0.33). An accurate cutoff value of ADC increase or diameter decrease for the early identification of R or NR lesions was not found. CONCLUSION: The pretreatment ADC value of a liver metastasis does not seem useful in predicting the CHT outcome. A trend towards early ADC increase, alone or occurring with dimensional decrease, may be a good indicator of a responding lesion.

Predicting Response to Exclusive Combined Radio-Chemotherapy in Naso-Oropharyngeal Cancer: The Role of Texture Analysis.

The aim of this work is to identify MRI texture features able to predict the response to radio-chemotherapy (RT-CHT) in patients with naso-oropharyngeal carcinoma (NPC-OPC) before treatment in order to help clinical decision making. Textural features were derived from ADC maps and post-gadolinium T1-images on a single MRI machine for 37 patients with NPC-OPC. Patients were divided into two groups (responders/non-responders) according to results from MRI scans and 18F-FDG-PET/CT performed at follow-up 3-4 and 12 months after therapy and biopsy. Pre-RT-CHT lesions were segmented, and radiomic features were extracted. A non-parametric Mann-Whitney test was performed. A p-value < 0.05 was considered significant. Receiver operating characteristic curves and area-under-the-curve values were generated; a 95% confidence interval (CI) was reported. A radiomic model was constructed using the LASSO algorithm. After feature selection on MRI T1 post-contrast sequences, six features were statistically significant: gldm_DependenceEntropy and DependenceNonUniformity, glrlm_RunEntropy and RunLengthNonUniformity, and glszm_SizeZoneNonUniformity and ZoneEntropy, with significant cut-off values between responder and non-responder group. With the LASSO algorithm, the radiomic model showed an AUC of 0.89 and 95% CI: 0.78-0.99. In ADC, five features were selected with an AUC of 0.84 and 95% CI: 0.68-1. Texture analysis on post-gadolinium T1-images and ADC maps could potentially predict response to therapy in patients with NPC-OPC who will undergo exclusive treatment with RT-CHT, being, therefore, a useful tool in therapeutical-clinical decision making.

Focal liver lesion classification and characterization in noncirrhotic liver: a prospective comparison of diffusion-weighted magnetic resonance-related parameters.

PURPOSE: The objective of this study was to prospectively verify if diffusion-weighted magnetic resonance (DwMR)-related parameters such as perfusion fraction (f) and slow diffusion coefficient (D), according to Le Bihan theory, are more effective than apparent diffusion coefficient (ADC) for classification and characterization of the more frequent focal liver lesions (FLLs) in noncirrhotic liver. METHODS: Sixty-seven patients underwent standard liver magnetic resonance imaging (MRI) and free-breath multi-b DwMR study. Two regions of interest were defined by 2 observers, including 1 FLL for each patient (21 hemangiomas, 21 focal nodular hyperplasias, 25 metastases) and part of surrounding parenchyma, respectively. For every FLL, D, f, and ADC were estimated both as absolute value and as ratio between FLL and surrounding parenchyma by fitting the reduced equation of the bicompartmental model to experimental data; t test, analysis of variance, and receiver operating characteristic analysis were performed. RESULTS: t Test showed significant differences in ADClesion, f lesion, D lesion, ADCratio, and D ratio values between benign and malignant FLLs, more pronounced for ADClesion (P < 0.0009) and ADCratio (P = 0.001). Applying cutoff values of 1.55 × 10 mm/s (ADClesion) and 0.89 (ADCratio), the DwMR study presented sensitivities and specificities, respectively, of 84% and 80% (for ADClesion), 72% and 80% (ADCratio). CONCLUSIONS: Apparent diffusion coefficient (by fitting procedures) better performs than do D and f in FLL classification, especially when its values are less than 1.30 or greater than 2.00 × 10 mm/s.

Imaging of human papilloma virus (HPV) related oropharynx tumour: what we know to date.

The tumours of head and neck district are around 3% of all malignancies and squamous cell carcinoma is the most frequent histotype, with rapid increase during the last two decades because of the increment of the infection due to human papilloma virus (HPV). Even if the gold standard for the diagnosis is histological examination, including the detection of viral DNA and transcription products, imaging plays a fundamental role in the detection and staging of HPV + tumours, in order to assess the primary tumour, to establish the extent of disease and for follow-up. The main diagnostic tools are Computed Tomography (CT), Positron Emission Tomography-Computed Tomography (PET-CT) and Magnetic Resonance Imaging (MRI), but also Ultrasound (US) and the use of innovative techniques such as Radiomics have an important role. Aim of our review is to illustrate the main imaging features of HPV + tumours of the oropharynx, in US, CT and MRI imaging. In particular, we will outline the main limitations and strengths of the various imaging techniques, the main uses in the diagnosis, staging and follow-up of disease and the fundamental differential diagnoses of this type of tumour. Finally, we will focus on the innovative technique of texture analysis, which is increasingly gaining importance as a diagnostic tool in aid of the radiologist.

Characterization of Mediastinal Bulky Lymphomas with FDG-PET-Based Radiomics and Machine Learning Techniques.

BACKGROUND: This study tested the diagnostic value of 18F-FDG PET/CT (FDG-PET) volumetric and texture parameters in the histological differentiation of mediastinal bulky disease due to classical Hodgkin lymphoma (cHL), primary mediastinal B-cell lymphoma (PMBCL) and grey zone lymphoma (GZL), using machine learning techniques. METHODS: We reviewed 80 cHL, 29 PMBCL and 8 GZL adult patients with mediastinal bulky disease and histopathological diagnoses who underwent FDG-PET pre-treatment. Volumetric and radiomic parameters were measured using FDG-PET both for bulky lesions (BL) and for all lesions (AL) using LIFEx software (threshold SUV ≥ 2.5). Binary and multiclass classifications were performed with various machine learning techniques fed by a relevant subset of radiomic features. RESULTS: The analysis showed significant differences between the lymphoma groups in terms of SUVmax, SUVmean, MTV, TLG and several textural features of both first- and second-order grey level. Among machine learning classifiers, the tree-based ensembles achieved the best performance both for binary and multiclass classifications in histological differentiation. CONCLUSIONS: Our results support the value of metabolic heterogeneity as an imaging biomarker, and the use of radiomic features for early characterization of mediastinal bulky lymphoma.

Added prognostic value of molecular imaging parameters over proliferation index in typical lung carcinoid: an [18F]FDG PET/CT and SSTR imaging study.

OBJECTIVE: This study was performed to evaluate the prognostic meaning of volumetric and semi-quantitative parameters measured using [18F]FDG PET/CT and somatostatin receptor (SSTR) imaging in patients with typical lung carcinoid (TC), and their relationship with proliferative index (Ki67). METHODS: We retrospectively reviewed 67 patients (38-94 years old, mean: 69.7) with diagnosis of TC who underwent [18F]FDG PET/CT and/or SSTR scintigraphy/SPECT with [111In]DTPA-Octreotide plus contrast-enhanced CT (CECT) at staging evaluation. All patients had Ki67 measured and a follow-up (FU) of at least 1 year. SSTR density (SSTRd) was calculated as the percentage difference of tumor/non-tumor ratio at 4 and 24 h post-injection. At PET/CT, metabolic activity was measured using SUVmax and SUVratio; volumetric parameters included MTV and TLG of the primary tumor, measured using the threshold SUV41%. ROC analysis, discriminant analysis and Kaplan-Meier curves (KM) were performed. RESULTS: 11 patients died during FU. Disease stage (localized versus advanced), SUVratio, SUVmax, Ki67, MTV and TLG were significantly higher in non-survivors than in survivors. ROC curves resulted statistically significant for Ki67, SUVratio, SUVmax, MTV and TLG. On multivariate analysis, stage of disease and TLG were significant independent predictors of overall survival (OS). In KM curves, the combination of disease stage and TLG identified four groups with significantly different outcomes (p < 0.005). Metabolic activity (SUVmax and SUVratio) was confirmed as significant independent prognostic factor for OS also in patients with advanced disease, with the best AUC using SUVmax. In patients with advanced and localized disease, SSTRd proved to be the best imaging prognostic factor for progression and for disease-free survival (DFS), respectively. In localized disease, SSTRd 31.5% identified two subgroups of patients with significant different DFS distribution and in advanced disease, a high cutoff value (58.5%) was a significant predictor of adverse prognosis. CONCLUSION: Volumetric and semi-quantitative parameters measured using [18F]FDG PET/CT and SSTR imaging combined with Ki67 may provide a reference for prognosis evaluation of patients with TC, to better stratify risk groups with the goal of developing individualized therapeutic strategies.

Role of Texture Analysis in Oropharyngeal Carcinoma: A Systematic Review of the Literature.

Human papilloma virus infection (HPV) is associated with the development of lingual and palatine tonsil carcinomas. Diagnosing, differentiating HPV-positive from HPV-negative cancers, and assessing the presence of lymph node metastases or recurrences by the visual interpretation of images is not easy. Texture analysis can provide structural information not perceptible to human eyes. A systematic literature search was performed on 16 February 2022 for studies with a focus on texture analysis in oropharyngeal cancers. We conducted the research on PubMed, Scopus, and Web of Science platforms. Studies were screened for inclusion according to the preferred reporting items for systematic reviews. Twenty-six studies were included in our review. Nineteen articles related specifically to the oropharynx and seven articles analysed the head and neck area with sections dedicated to the oropharynx. Six, thirteen, and seven articles used MRI, CT, and PET, respectively, as the imaging techniques by which texture analysis was performed. Regarding oropharyngeal tumours, this review delineates the applications of texture analysis in (1) the diagnosis, prognosis, and assessment of disease recurrence or persistence after therapy, (2) early differentiation of HPV-positive versus HPV-negative cancers, (3) the detection of cancers not visualised by imaging alone, and (4) the assessment of lymph node metastases from unknown primary carcinomas.