Trans-Arterial Stem Cell Injection (TASI): The Role of Interventional Radiology in Regenerative Medicine.

Regenerative medicine is taking a step forward in treating multiple diseases. The possibility of renewing damaged tissues with stem cells has become a topic of interest in recent decades. Still a relatively new research topic, many issues in this discipline are being addressed, from cell culturing to the study of different graft materials, and, moreover, cell delivery. For instance, direct intravenous injection has a big downfall regarding its lack of precision and poorly targeted treatment. Trans-arterial and direct percutaneous infusion to the aimed tissue/organ are both considered ideal for reaching the desired region but require image guidance to be performed safely and precisely. In this context, interventional radiology becomes pivotal for providing different cell delivery possibilities in every case. In this review, we analyze different basic stem cell therapy concepts and the current and future role of interventional radiology with a focus on trans-arterial delivery.

Survival After Transarterial Radioembolization in Patients with Unresectable Intrahepatic Cholangiocarcinoma: An Updated Meta-analysis and Meta-regression.

PURPOSE: Transarterial radioembolization (TARE) has emerged as a promising therapeutic approach for unresectable intrahepatic cholangiocarcinoma (ICCA). We updated our previous meta-analysis with meta-regression to explore the efficacy of TARE in the context of ICCA. METHODS: We searched PubMed and Scopus for studies published up to September 1, 2023. The primary outcome was overall survival. Secondary outcomes were tumor overall response rate, severe adverse events, and downstaging to surgery. Meta-analysis employed a random-effects model, and meta-regression was utilized to explore sources of heterogeneity. RESULTS: We included 27 studies, involving 1365 patients. Pooled survival estimates at 1, 2, and 3 years were 52.6%, 27%, and 16.8%, respectively. Meta-regression revealed that the proportion of patients naïve to treatment was the only pre-TARE predictor of survival (1-, 2-, and 3-year survival of 70%, 45%, and 36% for treatment-naïve patients, mean survival 19.7 months vs. 44%, 18%, and 7% for non-naïve patients, mean survival 12.2 months). Overall response according to RECIST 1.1 and mRECIST was 19.6% and 67%, respectively. Effective downstaging to surgery was possible in varying rates (3-54%); the mean survival in these patients was 34.8 months (1-, 2-, and 3-year survival of 100%, 87%, and 64%). About 45.7% of patients experienced adverse events, but only 5.9% were severe. CONCLUSIONS: Our study benchmarked the survival rates of patients undergoing TARE for unresectable ICCA and showed that this is a valid option in these patients, especially if naïve to previous treatments. Downstaging to surgery is feasible in selected patients with promising results.

Long-Term Outcomes of Balloon TACE for HCC: An European Multicentre Single-Arm Retrospective Study.

PURPOSE: To report response rates (using mRECIST), overall survival (OS), progression-free survival and local tumour recurrence-free survival (LRFS) of balloon-occluded transarterial chemoembolisation (bTACE) for hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Patients from five European centres treated with conventional or drug-eluting microsphere bTACE for HCC were included, and patients already lost to follow-up before 12 months were excluded. Possible factors contributing to LRFS and OS were evaluated with Cox proportional hazards models. RESULTS: Seventy-three patients were enrolled. The mean number of nodules per patient was 2.07(± 1.68), and the average maximum diameter of the nodules was 37 ± 19.9 mm. The response of the target lesion at 6 months was complete response (CR) in 58.9%, partial response (PR) in 28.8%, stable disease (SD) in 6.8% and progressive disease (PD) in 5.5%. The median follow-up time was 31 months; at the last follow-up, target tumour response was CR in 49.3%, PR in 12.3%, SD in 5.5% and PD 32.9%. Overall response at the last follow-up was CR in 17.8%, PR in 9.6%, SD 2.7% and PD in 69.9% (for new lesions in 37% of patients). Median OS was not reached; mean overall survival was 50.0 months, while median LRFS was 31.0 months. At uni- and multivariable analysis, only tumour maximum diameter was related to LRFS (hazard ratio [HR] = 1.021; 95% CI 1.004-1.038, P = 0.015). CONCLUSIONS: bTACE demonstrated high efficacy for HCC, with a complete response in 58.9% of patients, a median local recurrence-free survival of 31.0 months and a mean overall survival of 50.0 months.

Image-Guided Minimally Invasive Treatment Options for Degenerative Lumbar Spine Disease: A Practical Overview of Current Possibilities.

Lumbar back pain is one of the main causes of disability around the world. Most patients will complain of back pain at least once in their lifetime. The degenerative spine is considered the main cause and is extremely common in the elderly population. Consequently, treatment-related costs are a major burden to the healthcare system in developed and undeveloped countries. After the failure of conservative treatments or to avoid daily chronic drug intake, invasive treatments should be suggested. In a world where many patients reject surgery and prefer minimally invasive procedures, interventional radiology is pivotal in pain management and could represent a bridge between medical therapy and surgical treatment. We herein report the different image-guided procedures that can be used to manage degenerative spine-related low back pain. Particularly, we will focus on indications, different techniques, and treatment outcomes reported in the literature. This literature review focuses on the different minimally invasive percutaneous treatments currently available, underlining the central role of radiologists having the capability to use high-end imaging technology for diagnosis and subsequent treatment, allowing a global approach, reducing unnecessary surgeries and prolonged pain-reliever drug intake with their consequent related complications, improving patients' quality of life, and reducing the economic burden.

An Apparent Diffusion Coefficient-Based Machine Learning Model Can Improve Prostate Cancer Detection in the Grey Area of the Prostate Imaging Reporting and Data System Category 3: A Single-Centre Experience.

The Prostate Imaging and Reporting Data System (PI-RADS) has a key role in the management of prostate cancer (PCa). However, the clinical interpretation of PI-RADS 3 score lesions may be challenging and misleading, thus postponing PCa diagnosis to biopsy outcome. Multiparametric magnetic resonance imaging (mpMRI) radiomic analysis may represent a stand-alone noninvasive tool for PCa diagnosis. Hence, this study aims at developing a mpMRI-based radiomic PCa diagnostic model in a cohort of PI-RADS 3 lesions. We enrolled 133 patients with 155 PI-RADS 3 lesions, 84 of which had PCa confirmation by fusion biopsy. Local radiomic features were generated from apparent diffusion coefficient maps, and the four most informative were selected using LASSO, the Wilcoxon rank-sum test (p < 0.001), and support vector machines (SVMs). The selected features where augmented and used to train an SVM classifier, externally validated on a holdout subset. Linear and second-order polynomial kernels were exploited, and their predictive performance compared through receiver operating characteristics (ROC)-related metrics. On the test set, the highest performance, equally for both kernels, was specificity = 76%, sensitivity = 78%, positive predictive value = 80%, and negative predictive value = 74%. Our findings substantially improve radiologist interpretation of PI-RADS 3 lesions and let us advance towards an image-driven PCa diagnosis.

Transverse prostate maximum sectional area can predict clinically significant prostate cancer in PI-RADS 3 lesions at multiparametric magnetic resonance imaging.

Background: To evaluate multiparametric magnetic resonance imaging (mpMRI) parameters, such as TransPA (transverse prostate maximum sectional area), TransCGA (transverse central gland sectional area), TransPZA (transverse peripheral zone sectional area), and TransPAI (TransPZA/TransCGA ratio) in predicting prostate cancer (PCa) in prostate imaging reporting and data system (PI-RADS) 3 lesions. Methods: Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV), the area under the receiver operating characteristic curve (AUC), and the best cut-off, were calculated. Univariate and multivariate analyses were carried out to evaluate the capability to predict PCa. Results: Out of 120 PI-RADS 3 lesions, 54 (45.0%) were PCa with 34 (28.3%) csPCas. Median TransPA, TransCGA, TransPZA and TransPAI were 15.4cm2, 9.1cm2, 5.5cm2 and 0.57, respectively. At multivariate analysis, location in the transition zone (OR=7.92, 95% CI: 2.70-23.29, P<0.001) and TransPA (OR=0.83, 95% CI: 0.76-0.92, P<0.001) were independent predictors of PCa. The TransPA (OR=0.90, 95% CI: 0.082-0.99, P=0.022) was an independent predictor of csPCa. The best cut-off of TransPA for csPCa was 18 (Sensitivity 88.2%, Specificity 37.2%, PPV 35.7%, NPV 88.9%). The discrimination (AUC) of the multivariate model was 0.627 (95% CI: 0.519-0.734, P<0.031). Conclusions: In PI-RADS 3 lesions, the TransPA could be useful in selecting patients requiring biopsy.

MRI Appearance of Focal Lesions in Liver Iron Overload.

Liver iron overload is defined as an accumulation of the chemical element Fe in the hepatic parenchyma that exceeds the normal storage. When iron accumulates, it can be toxic for the liver by producing inflammation and cell damage. This can potentially lead to cirrhosis and hepatocellular carcinoma, as well as to other liver lesions depending on the underlying condition associated to liver iron overload. The correct assessment of liver iron storage is pivotal to drive the best treatment and prevent complication. Nowadays, magnetic resonance imaging (MRI) is the best non-invasive modality to detect and quantify liver iron overload. However, due to its superparamagnetic properties, iron provides a natural source of contrast enhancement that can make challenging the differential diagnosis between different focal liver lesions (FLLs). To date, a fully comprehensive description of MRI features of liver lesions commonly found in iron-overloaded liver is lacking in the literature. Through an extensive review of the published literature, we aim to summarize the MRI signal intensity and enhancement pattern of the most common FLLs that can occur in liver iron overload.

Evaluating the performance of clinical and radiological data in predicting prostate cancer in prostate imaging reporting and data system version 2.1 category 3 lesions of the peripheral and the transition zones.

PURPOSE: To define the value of clinical and radiological data, using multiparametric magnetic resonance imaging (mpMRI), to predict prostate cancer (PCa) in prostate imaging reporting and data system version 2.1 (PIRADSv2.1) 3 lesions of the peripheral and the transition zones (PZ and TZ). METHODS: The mpMRI of patients with PIRADSv2.1 3 lesions who had undergone fusion targeted biopsy was reviewed. Morphological pattern, diffusion parameters and vascularisation were evaluated. The radiological/histopathological data of benign and malignant lesions, between the PZ and TZ were compared. Univariate and multivariate analyses were carried out to identify the clinical and radiological data capable of predicting PCa. RESULTS: One hundred and twenty-three lesions were assessed, 93 (76%) in the PZ and 30 (24%) in the TZ. Of these, 56 (46%) were PCa and 67 (54%) were benign. The majority of the PCas were Grade Group System (GGS) 1 (38%) and GGS 2 (39%); tumours having a GGS ≥ 3 were more frequently in the TZ (p = 0.02). Univariate analysis showed a significant correlation between PCa and prostate volume, prostate-specific antigen (PSA) density, lesion zone and the apparent diffusion coefficient. At multivariate logistic regression PSA density > 0.15 ng/ml/ml {Odds ratio [OR] 2.38; p = 0.001} and lesion zone (i.e. TZ OR 7.55) were independent predictors of PCa (all p ≤ 0.04). CONCLUSION: In solitary PIRADSv2.1 3 lesions, the most important predictive factor was the location zone, with a much greater risk for TZ lesions.

State-of-the-art review on the correlations between pathological and magnetic resonance features of cirrhotic nodules.

Hepatocellular carcinoma (HCC) has become the second greatest cause of cancer-related mortality worldwide and the newest advancements in liver imaging have improved the diagnosis of both overt malignancies and premalignant lesions, such as cirrhotic or dysplastic nodules, which is crucial to improve overall patient survival rate and to choose the best treatment options. The role of Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) has grown in the last 20 years. In particular, the introduction of hepatospecific contrast agents has strongly increased the definition of precursor nodules and detection of high-grade dysplastic nodules and early HCCs. Nevertheless, the diagnosis of liver tumours in cirrhotic patients sometimes remains challenging for radiologists, thus, in doubtful cases, biopsy and histological analysis become critical in clinical practice. This current review briefly summarizes the history of imaging and histology for HCC, covering the newest techniques and their limits. Then, the article discusses the links between radiological and pathological characteristics of liver lesions in cirrhotic patients, by describing the multistep process of hepatocarcinogenesis. Explaining the evolution of pathologic change from cirrhotic nodules to malignancy, the list of analyzed lesions provides regenerative nodules, low-grade and high-grade dysplastic nodules, small HCC and progressed HCC, including common subtypes (steatohepatitic HCC, scirrhous HCC, macrotrabecular massive HCC) and more rare forms (clear cell HCC, chromophobe HCC, neutrophil-rich HCC, lymphocyte-rich HCC, fibrolamellar HCC). The last chapter covers the importance of the new integrated morphological-molecular classification and its association with radiological features.