Il linfonodo sentinella nel melanoma: correlazione tra captazione e positività

Abstract: L’individuazione del linfonodo sentinella nei pazienti affetti da melanoma cutaneo con un indice Breslow superiore a 0,76 mm rappresenta uno strumento prognostico fondamentale nel trattamento di questi pazienti. In questo lavoro abbiamo voluto osservare se vi è una correlazione tra il grado di captazione del tracciante radioattivo e l’effettiva positività del linfonodo sentinella. Per fare ciò, sono stati valutati 45 pazienti con diagnosi di melanoma cutaneo. La linfoscintigrafia nella totalità dei casi è stata effettuata il giorno stesso dell’intervento chirurgico. Durante l’operazione il LS veniva identificato, con una sonda probe che valutava la radioattività del radiocolloide iniettato, e rimosso. In circa il 31,8% dei casi il LS risultava sede di metastasi da melanoma e 68,2% esente da ripetizioni. Nei pazienti con positività del LS si era potuta osservare un conteggio cutaneo con sonda gamma probe racchiuso in un intervallo di 100-5200 cps e nei pazienti con LS negativo tra 300-3300 cps. L’individuazione del LS tramite linfoscintigrafia rappresenta una tecnica semplice, non invasiva, di facile realizzazione che permette al chirurgo di effettuare un’asportazione più sicura di quello che rappresenta il primo linfonodo, che potrebbe essere interessato da un’invasione metastatica di cellule neoplastiche. La radioattività emessa dal tracciante radioattivo iniettato per la sua individuazione sembrerebbe non avere correlazioni con la positività all’esame istologico del LS

A straightforward multiparametric quality control protocol for proton magnetic resonance spectroscopy: Validation and comparison of various 1.5 T and 3 T clinical scanner systems

Purpose: The aim of this study was to propose and validate across various clinical scanner systems a straightforward multiparametric quality assurance procedure for proton magnetic resonance spectroscopy (MRS). Methods: Eighteen clinical 1.5 T and 3 T scanner systems for MRS, from 16 centres and 3 different manufacturers, were enrolled in the study. A standard spherical water phantom was employed by all centres. The acquisition protocol included 3 sets of single (isotropic) voxel (size 20 mm) PRESS acquisitions with unsuppressed water signal and acquisition voxel position at isocenter as well as off-center, repeated 4/5 times within approximately 2 months. Water peak linewidth (LW) and area under the water peak (AP) were estimated. Results: LW values [mean (standard deviation)] were 1.4 (1.0) Hz and 0.8 (0.3) Hz for 3 T and 1.5 T scanners, respectively. The mean (standard deviation) (across all scanners) coefficient of variation of LW and AP for different spatial positions of acquisition voxel were 43% (20%) and 11% (11%), respectively. The mean (standard deviation) phantom T2 values were 1145 (50) ms and 1010 (95) ms for 1.5 T and 3 T scanners, respectively. The mean (standard deviation) (across all scanners) coefficients of variation for repeated measurements of LW, AP and T2 were 25% (20%), 10% (14%) and 5% (2%), respectively. Conclusions: We proposed a straightforward multiparametric and not time consuming quality control protocol for MRS, which can be included in routine and periodic quality assurance procedures. The protocol has been validated and proven to be feasible in a multicentre comparison study of a fairly large number of clinical 1.5 T and 3 T scanner systems

Sequence of events leading to primary biliary cholangitis

: Primary biliary cholangitis (PBC) is a chronic cholestatic liver disease that is observed more frequently in middle-aged women. This disorder is considered an autoimmune disease, since liver injury is sustained by the presence of self-directed antimitochondrial antibodies targeting the bile duct cells. The prognosis may vary depending on an early diagnosis and response to therapy. However, nearly a third of patients can progress to liver cirrhosis, thus requiring a liver transplant. Traditional immunosuppressive therapies, commonly employed for other autoimmune diseases, have limited effects on PBC. In fact, dramatic functional changes that occur in the biliary epithelium in the course of inflammation play a major role in perpetuating the injury. In this minireview, after a background on the disease and possible predisposing factors, the sequential cooperation of cellular/molecular events leading to end-stage PBC is discussed in detail. The rise and maintenance of the autoimmune process, as well as the response of the biliary epithelia during inflammatory injury, are key factors in the progression of the disease. The so-called "ductular reaction (DR)", intended as a reactive expansion of cells with biliary phenotype, is a process frequently observed in PBC and partially understood. However, recent findings suggest a strict relationship between this pathological picture and the progression to liver fibrosis, cell senescence, and loss of biliary ducts. All these issues (onset of chronic inflammation, changes in secretive and proliferative biliary functions, DR, and its relationship with other pathological events) are discussed in this manuscript in an attempt to provide a snapshot, for clinicians and researchers, of the most relevant and sequential contributors to the progression of this human cholestatic disease. We believe that interpreting this disorder as a multistep process may help identify possible therapeutic targets to prevent evolution to severe disease