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Although most cancers are considered predominantly systemic processes, this may not hold true for hepatocellular carcinoma (HCC). The literature regarding patterns of progression of HCC (local versus systemic) has been relatively sparse. Our objectives were to: (1) analyze patterns of progression in HCC patients presenting with intrahepatic disease from initial treatment until death, and (2) identify clinically relevant risk factors for the development of metastases. Over a 9-year period, 285 patients treated with transarterial locoregional therapies underwent scheduled imaging follow-up from treatment until death and were categorized by pattern of progression: (i) intrahepatic (increased tumor enhancement/size, development/progression of vascular invasion, new hepatic lesions) progression or (ii) extrahepatic (adrenal/bone/lung/lymph node) metastases. Uni/multivariate analyses assessing the risk factors for the development of metastases were performed. The median time from last scan to death was 2.4 months (interquartile range: 1.3-4.8 months). The time to development of metastases, vascular invasion, and/or new lesions was 13.8 months (confidence interval: 11.3-17.7 months). Of the 209 patients followed until death, only 50 developed extrahepatic metastases (24%). Multivariate analyses identified age <65 years (P = 0.038), alpha-fetoprotein >200 ng/mL (P = 0.04), and vascular invasion (P = 0.017) as significant predictors of metastases development. CONCLUSION: Knowledge of the risk factors associated with the development of metastases may help guide assessment of patient prognosis. Because 76% of patients presenting with local disease treated with locoregional therapies die without developing extrahepatic metastases, the notion of HCC as a systemic disease, as detected by imaging, may be reconsidered.  相似文献   
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A 41-year-old woman with metastatic melanoma was admitted to the hospital because of syncopal episodes, which had developed after the administration of an experimental chemotherapy agent that targeted Notch signaling, as part of a phase I clinical trial. Cardiac monitoring revealed recurrent episodes of polymorphic ventricular tachycardia correlating with the patient''s syncope. Investigations into the cause of the arrhythmia led to the discovery of metastatic lesions within the left ventricular myocardium. In presenting this case of polymorphic ventricular tachycardia as the antemortem clinical manifestation of metastatic melanoma involving the heart, we discuss the importance of recognizing that cardiac metastases can manifest themselves as arrhythmias in patients with malignant melanoma who are undergoing active anticancer treatment.Key words: Antineoplastic chemotherapy protocols/adverse effects, arrhythmias, cardiac/chemically induced/diagnosis/physiopathology/therapy, coronary disease/complications, heart neoplasms/pathology/secondary, melanoma/pathology, myocardium/pathology, receptors, notch/metabolism, recurrence/prevention & control, syncope/etiology, tachycardia, ventricular/chemically induced/etiologyA woman with metastatic melanoma was admitted to the hospital because of syncope and was diagnosed with episodes of polymorphic ventricular tachycardia (VT). The episodes developed after the administration of an experimental chemotherapy agent that targeted Notch signaling as part of a phase I clinical trial. The patient was found to have metastatic lesions in her myocardium. We present and discuss this case of polymorphic VT as a manifestation of cardiac metastasis in malignant melanoma in a patient who was undergoing active anticancer treatment.  相似文献   
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Background

Onchocerciasis has been implicated in the pathogenesis of epilepsy. The debate on a potential causal relationship between Onchocerca volvulus and epilepsy has taken a new direction in the light of the most recent epidemic of nodding syndrome.

Objective

To document MRI changes in people with different types of epilepsy and investigate whether there is an association with O. volvulus infection.

Methods

In a prospective study in southern Tanzania, an area endemic for O. volvulus with a high prevalence of epilepsy and nodding syndrome, we performed MRI on 32 people with epilepsy, 12 of which suffered from nodding syndrome. Polymerase chain reaction (PCR) of O. volvulus was performed in skin and CSF.

Results

The most frequent abnormalities seen on MRI was atrophy (twelve patients (37.5%)) followed by intraparenchymal pathologies such as changes in the hippocampus (nine patients (28.1%)), gliotic lesions (six patients (18.8%)) and subcortical signal abnormalities (three patients (9.4%)). There was an overall trend towards an association of intraparenchymal cerebral pathologies and infection with O. volvulus based on skin PCR (Fisher''s Exact Test p=0.067) which was most pronounced in children and adolescents with nodding syndrome compared to those with other types of epilepsy (Fisher''s Exact Test, p=0.083). Contrary to skin PCR results, PCR of CSF was negative in all patients.

Conclusion

The observed trend towards an association of intraparenchymal cerebral pathological results on MRI and a positive skin PCR for O. volvulus despite negative PCR of CSF is intriguing and deserves further attention.  相似文献   
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The aim of this study was to develop a prediction equation for estimating the total widths of the mandibular permanent canines and premolars (TCPW) using the total widths of the mandibular first permanent molars and incisors (TWFMI). The sample comprised 288 mandibular dental casts of orthodontic patients (106 males and 182 females, average age 13.8 and 14.4 years, respectively). A digital vernier calliper was used to measure the mesiodistal tooth widths from the mandibular right to the left first permanent molar. An independent t-test was used to determine any gender difference and a multiple linear regression equation to predict TCPW using TWFMI. A paired t-test was used to compare the actual and predicted values of the canines and premolars. The results showed a statistically significant difference (P < 0.01) between the mesiodistal tooth widths of males and females. A moderate correlation and determination coefficient between TCPW and TWFMI was found (r = 0.64 to r = 0.67 and r(2) = 0.41 to r(2) = 0.44, respectively). There was no significant difference between actual and predicted values for males and females. The regression equations proposed are a good prediction method to determine TCPW.  相似文献   
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