Valutazione mediante TC di perfusione della risposta dell'epatocarcinoma avanzato al trattamento con sorafenib.

RIASSUNTO ANALITICO Scopo della tesi è valutare l'applicabilità di un protocollo per lo studio perfusionale quantitativo con TC a 64 canali dell'HCC avanzato in pazienti sottoposti a terapia antiangiogenetica con sorafenib, al fine di predire la risposta precoce al trattamento utilizzando il valore di alfafetoproteina plasmatica come marcatore biochimico di riferimento. Lo studio sperimentale ha coinvolto 7 pazienti (6 maschi, 1 femmina; età compresa fra 48 e 83 anni, media 69 anni) con diagnosi di HCC sottoposti a valutazione del parenchima epatico con TC a 64 canali, per un totale di 10 HCC. Tutti i pazienti hanno effettuato TC perfusionale immediatamente prima di iniziare il trattamento con sorafenib (tempo zero); sono stati inoltre effettuati controlli mediante lo stesso protocollo TC perfusionale sulle stesse lesioni di interesse dopo uno e/o tre mesi. In tutti i pazienti, inoltre, è stato misurato il valore di alfafetoproteina (αFP) plasmatica al tempo zero e in occasione dei successivi controlli TC. Utilizzando un software dedicato sono stati calcolati sulle lesioni HCC e sul parenchima epatico circostante i seguenti parametri perfusionali: Blood Flow (BF), Blood Volume (BV), Mean Transit Time (MTT), Hepatic Arterial Fraction (HAF) e Permeability-Surface Product (PS). Tali parametri, misurati al tempo zero rispettivamente sulle lesioni HCC e nel parenchima epatico circostante, sono stati confrontati fra loro; sono stati quindi confrontati fra loro gli stessi parametri perfusionali misurati al tempo zero e ai successivi controlli TC. É stata infine calcolata la correlazione fra ciascun parametro perfusionale al tempo zero e la variazione di αFP fra l'ultimo controllo TC e il valore di essa misurato al tempo zero. Al tempo zero i valori di BV, BF, HAF e PS erano significativamente maggiori nelle lesioni HCC rispetto al parenchima epatico circostante, mentre MTT è risultato significativamente minore. Dopo terapia con sorafenib i valori di MTT erano significativamente aumentati rispetto al tempo zero. Inoltre, si è trovata una correlazione statisticamente significativa fra allungamento di MTT e riduzione del livello plasmatico di αFP dopo la terapia con sorafenib rispetto al tempo zero, nonché una correlazione inversa fra valori assoluti di MTT al tempo zero e riduzione del livello plasmatico di αFP dopo terapia. I risultati ottenuti mostrano che l'analisi perfusionale quantitativa mediante TC permette di ottenere informazioni sullo stato del microcircolo neoangiogenetico in accordo con il substrato fisiopatologico dell'HCC. Fra questi, il valore di MTT calcolato al tempo zero si è rivelato in grado di predire l'eventuale successiva risposta biochimica alla terapia con sorafenib. ABSTRACT The aim of this study is to evaluate the feasibility of a 64-row computed tomography (CT) perfusion protocol for functional assessment of advanced hepatocellular carcinoma (HCC) in patients candidate to or undergoing antiangiogenic therapy with sorafenib, in order to predict treatment outcome using serum alphafetoprotein (αFP) levels as a reference biochemical marker. Seven patients (6 male and 1 female, age 48-83 years, average 69 years) with previously diagnosed HCC were enrolled in the study. All patients underwent 64-row contrast-enhanced CT for the evaluation of the liver, for a total of 10 HCC lesions. CT perfusion imaging was performed on all patients immediately before the beginning of sorafenib therapy (baseline), and one and/or three months thereafter on the same HCC lesions. Serum αFP levels were also measured at baseline and at every follow-up CT examination. Using dedicated software, the following CT perfusion parameters were calculated on HCC lesions and on the surrounding liver parenchyma: Blood Flow (BF), Blood Volume (BV), Mean Transit Time (MTT), Hepatic Arterial Fraction (HAF), and Permeability-Surface Product (PS). Baseline HCC perfusion parameters were compared with those of the surrounding liver parenchyma, as well as with follow-up HCC perfusion values. In addition, the correlation between each baseline CT perfusion value and the difference between follow-up and baseline serum αFP was calculated. Baseline BV, BF, HAF, and PS were significantly higher, while MTT was significantly lower in HCC than in the surrounding liver parenchyma. After sorafenib therapy, MTT was significantly increased compared with baseline. Moreover, a statistically significant correlation between MTT prolongation and serum αFP after treatment compared with baseline was found, as well as an inverse correlation between absolute MTT values at baseline and post-therapy serum αFP reduction. In conclusion, quantitative CT perfusion analysis allows to obtain information about the neoangiogenetic microcirculation that is in line with HCC pathophysiology. Baseline MTT has the potential to be used as an early predictor of biochemical response to sorafenib therapy

The polymorphism L412F in TLR3 inhibits autophagy and is a marker of severe COVID-19 in males

The polymorphism L412F in TLR3 has been associated with several infectious diseases. However, the mechanism underlying this association is still unexplored. Here, we show that the L412F polymorphism in TLR3 is a marker of severity in COVID-19. This association increases in the sub-cohort of males. Impaired macroautophagy/autophagy and reduced TNF/TNFα production was demonstrated in HEK293 cells transfected with TLR3L412F-encoding plasmid and stimulated with specific agonist poly(I:C). A statistically significant reduced survival at 28 days was shown in L412F COVID-19 patients treated with the autophagy-inhibitor hydroxychloroquine (p = 0.038). An increased frequency of autoimmune disorders such as co-morbidity was found in L412F COVID-19 males with specific class II HLA haplotypes prone to autoantigen presentation. Our analyses indicate that L412F polymorphism makes males at risk of severe COVID-19 and provides a rationale for reinterpreting clinical trials considering autophagy pathways. Abbreviations: AP: autophagosome; AUC: area under the curve; BafA1: bafilomycin A1; COVID-19: coronavirus disease-2019; HCQ: hydroxychloroquine; RAP: rapamycin; ROC: receiver operating characteristic; SARS-CoV-2: severe acute respiratory syndrome coronavirus 2; TLR: toll like receptor; TNF/TNF-α: tumor necrosis factor

Adhesive Small Bowel Occlusion: which CT signs predict surgery?

- Objectives: To determine in adhesive small bowel occlusion (ASBO), which MDCT findings are predictive for the failure of a non-operative management (NOM), of Gastrografin® test outcome and finally for the need of surgery. - Methods and Materials: From January 2015 to April 2017 we examined 137 admissions for ASBO: 71 Females, 66 Males, mean age 69 years (10-97), at our first level Emergency Department (ED). We excluded the patients without an adherential occlusion and those patients with spontaneous resolution of the bowel occlusion before the Gastrografin® test. This test is based on administration of the water soluble contrast (per os or via NGT) and to follow the progression of the contrast by means of seriated abdominal X-rays. It is considered successful if the cecum is opacified within eight hours. The MDCT parameters, taken in consideration, were twelve: maximum caliber of the bowel; wall thickness greater than 5mm; parietal pneumatosis; presence or absence of peritoneal free abdominal fluid (FAF), peritoneal fluid density (measured in Hounsfield Units-H.U.); whirl sign; number of transition points; closed loop obstruction; small bowel feces sign; reduced bowel wall enhancement (RBE); mesenteric fluid congestion and fat notch sign. The peritoneal fluid density has been considered measurable in the 84 admissions in which FAF, identified on MDCT, resulted to be sized >3cm2. The HU was measured by a round region of interest (ROI) positioned in the largest and lower pool of FAF (to include eventual blood stratifications) avoiding adjacent structures. A sensitivity analysis was performed to determine a high-density HU threshold. The FAF density in patients who underwent therapeutic laparotomy due to ischemia was compared with those successfully discharged without surgical approach. We evaluated the previously mentioned MDCT parameters: a) in all the patients that underwent surgery (n=86), b) in the group of patients treated surgically owing to ischemia (n=22), c) in the patients treated successfully with NOM implemented by Gastrografin® test (n=51) and d) in patients that underwent failed NOM implemented by Gastrografin® test (n=56) to find out any MDCT sign predictive of NOM failure. - Results: The RBE resulted to be the more significant MDCT parameter (p value: 14,5 UH resulted to need surgery due to ischemia with a sensitivity of 79% and specificity of 55%, PPV of 34% and NPV 90% an accuracy of 60% and a Youden Index of 0,34. The other MDCT parameters did not show any significant correlation. In our study no MDCT sign resulted to be significant in prediction of a failure of NOM performed with Gastrografin® test. - Conclusions: In ASBO, MDCT is fundamental for the management of the patients. Among the MDCT findings, RBE resulted significant in predicting the need of a surgical approach in general; while thickness greater than 5mm, presence of peritoneal fluid, closed loop obstruction, RBE and an increased peritoneal fluid density ( >14,5 UH) are useful to elaborate a model to predict surgery due to ischemic complications. No MDCT parameter resulted to be significant in prediction of a failure of NOM implemented with Gastrografin® test

CT colonography with rectal iodine tagging: Feasibility and comparison with oral tagging in a colorectal cancer screening population

PURPOSE: To evaluate feasibility, diagnostic performance, patient acceptance, and overall examination time of CT colonography (CTC) performed through rectal administration of iodinated contrast material. MATERIALS AND METHODS: Six-hundred asymptomatic subjects (male:female=270:330; mean 63 years) undergoing CTC for colorectal cancer screening on an individual basis were consecutively enrolled in the study. Out of them, 503 patients (group 1) underwent CTC with rectal tagging, of which 55 had a total of 77 colonic lesions. The remaining 97 patients (group 2) were randomly selected to receive CTC with oral tagging of which 15 had a total of 20 colonic lesions. CTC findings were compared with optical colonoscopy, and per-segment image quality was visually assessed using a semi-quantitative score (1=poor, 2=adequate, 3=excellent). In 70/600 patients (11.7%), CTC was performed twice with both types of tagging over a 5-year follow-up cancer screening program. In this subgroup, patient acceptance was rated via phone interview two weeks after CTC using a semi-quantitative scale (1=poor, 2=fair, 3=average, 4=good, 5=excellent). RESULTS: Mean per-polyp sensitivity, specificity, positive and negative predictive values of CTC with rectal vs oral tagging were 96.1% (CI95% 85.4÷99.3%) vs 89.4% (CI95% 65.4÷98.1%), 95.3% (CI95% 90.7÷97.8%) vs 95.8% (CI95% 87.6÷98.9%), 86.0% (CI95% 73.6÷93.3) vs 85.0% (CI95% 61.1÷96.0%), and 98.8% (CI95% 95.3÷99.8%) vs 97.2% (CI95% 89.4÷99.5%), respectively (p>0.05). Polyp detection rates were not statistically different between groups 1 and 2 (p>0.05). Overall examination time was significantly shorter with rectal than with oral tagging (18.3±3.5 vs 215.6±10.3 minutes, respectively; p<0.0001). CONCLUSIONS: Rectal iodine tagging can be an effective alternative to oral tagging for CTC with the advantages of greater patient acceptance and lower overall examination time

MRI tumor volume reduction rate vs tumor regression grade in the pre-operative re-staging of locally advanced rectal cancer after chemo-radiotherapy

OBJECTIVE: To compare tumor volume reduction rate (TVRR) measured by MR volumetry after preoperative chemoradiotherapy (CRT) and pathological tumor regression grade (TRG) in locally advanced rectal cancer (LARC). MATERIAL AND METHODS: In total, 20 patients with LARC (cT3-T4) treated with CRT followed by Total Mesorectal Excision (TME) between April 2011 and April 2013 were analyzed retrospectively. Pre- and post- CRT tumor volumes (MR volumetry) were measured on 3D MR sequences. TVRR was determined using the equation TVRR (%)=(pre-CRT tumor volume-post-CRT tumor volume)×100/pre-CRT tumor volume. The downstaging (defined as ypT0-T2) of tumor mass was evaluated and the correlation between TVRR and TRG was calculated with the method proposed by Dworak using the Spearman rank test. RESULTS: The median TVRR was 77.3% (range, 26.4-99.3%); TVRR was >60% in 18 cases (90%) and in 8 of these patients (44.4 %) it was >80%. Downstaging of tumor lesions was obtained in 15 patients (75%). In 4 cases there was a complete tumor regression (TRG4) at histological examination and in the same patients there was also a TVRR>80% measured by MR volumetry. A statistically significant correlation between TVRR and TRG (rs=0.5466, p=0.0126) was observed. CONCLUSION: TVRR after preoperative CRT correlates with TRG in LARC. The MR volumetry is a prognostic factor to estimate the tumor response after preoperative CRT. TVRR data may be an useful biomarker for tailoring surgery and postoperative adjuvant chemotherapy. Copyright © 2015. Published by Elsevier Ireland Ltd

Visual impairment in FOXG1-mutated individuals and mice

The Forkead Box G1 (FOXG1 in humans, Foxg1 in mice) gene encodes for a DNA-binding transcription factor, essential for the development of the telencephalon in mammalian forebrain. Mutations in FOXG1 have been reported to be involved in the onset of Rett Syndrome, for which sequence alterations of MECP2 and CDKL5 are known. While visual alterations are not classical hallmarks of Rett syndrome, an increasing body of evidence shows visual impairment in patients and in MeCP2and CDKL5 animal models. Herein we focused on the functional role of FOXG1 in the visual system of animal models (Foxg1+/Cre mice) and of a cohort of subjects carrying FOXG1 mutations or deletions. Visual physiology of Foxg1+/Cre mice was assessed by visually evoked potentials, which revealed a significant reduction in response amplitude and visual acuity with respect to wild-type littermates. Morphological investigation showed abnormalities in the organization of excitatory/inhibitory circuits in the visual cortex. No alterations were observed in retinal structure. By examining a cohort of FOXG1-mutated individuals with a panel of neuro-ophthalmological assessments, we found that all of them exhibited visual alterations compatible with high-level visual dysfunctions. In conclusion our data show that Foxg1 haploinsufficiency results in an impairment of mouse and human visual cortical function

Potent Mitogenicity of the RET/PTC3 Oncogene Correlates with Its Prevalence in Tall-Cell Variant of Papillary Thyroid Carcinoma

The tall-cell variant (TCV) of papillary thyroid carcinoma (PTC), characterized by tall cells bearing an oxyphilic cytoplasm, is more clinically aggressive than conventional PTC. RET tyrosine kinase rearrangements, which represent the most frequent genetic alteration in PTC, lead to the recombination of RET with heterologous genes to generate chimeric RET/PTC oncogenes. RET/PTC1 and RET/PTC3 are the most prevalent variants. We have found RET rearrangements in 35.8% of TCV (14 of 39 cases). Whereas the prevalences of RET/PTC1 and RET/PTC3 were almost equal in classic and follicular PTC, all of the TCV-positive cases expressed the RET/PTC3 rearrangement. These findings prompted us to compare RET/PTC3 and RET/PTC1 in an in vitro thyroid model system. We have expressed the two oncogenes in PC Cl 3 rat thyroid epithelial cells and found that RET/PTC3 is endowed with a strikingly more potent mitogenic effect than RET/PTC1. Mechanistically, this difference correlated with an increased signaling activity of RET/PTC3. In conclusion, we postulate that the correlation between the RET/PTC rearrangement type and the aggressiveness of human PTC is related to the efficiency with which the oncogene subtype delivers mitogenic signals to thyroid cells