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BackgroundThere is currently no worldwide consensus for the management of hepatocellular carcinoma (HCC) with portal vein tumor thrombus (PVTT). We evaluated the efficacy of stereotactic body radiotherapy (SBRT) as the initial treatment for HCC with extensive PVTT based on a relatively large number of patients.MethodsIn our multidisciplinary approach for patients with hepatobiliary tumors, SBRT is recommended for unresectable HCC with PVTT or those with contraindication for transarterial chemoembolization (TACE). The aim is to shrink the tumor thrombus and preserve adequate portal venous flow, thus facilitating subsequent treatments such as TACE and tumor resection. In the present study, 70 continuous cases of HCC patients with extensive PVTT initially treated with SBRT were studied. The median follow-up period was 9.5 months (range, 1.0–21.0 months). The dynamic changes of tumor thrombosis with time after SBRT were also analyzed.ResultsThe median survival time for the whole group was 10.0 months (95% CI, 7.7–12.3 months), with a 6- and 12-month overall survival (OS) rate of 67.3%, and 40.0% respectively. Patients who received combined SBRT and TACE showed significantly longer OS than those without indication for TACE after SBRT (12.0 ± 1.6 vs. 3.0 ± 1.0 months). Patients with good response to radiation usually had better survival. SBRT was well tolerated in our patient series.ConclusionsIn conclusion, SBRT used as the initial treatment for HCC patients with extensive PVTT originally unsuitable for resection or TACE can achieve adequate thrombus shrinkage and portal vein flow restoration in the majority of cases. It could thus offer the patients an opportunity to undergo further treatment such as resection or TACE procedure. Such therapeutic strategy may result in survival advantage, especially for those who do receive combined modality with SBRT.

ObjectivesTo explore the areas at highest risk for postoperative pancreatic cancer local recurrence according to the spatial location of local failures, with the aim to provide a precise target volume for pancreatic cancer adjuvant radiotherapy.MethodsPatients with pancreatic cancer who had undergone surgery for the primary tumor in pancreas at our institution from January 2010 to August 2015 were retrospectively analyzed. All local recurrences were plotted on the computed tomography (CT) image of a representative patient according to their relative coordinates to superior mesenteric artery (SMA) or celiac axis (CA). Adjuvant radiation clinical target volume (CTV)-90 and CTV-80 were created to cover 90 % and 80 % plotted recurrences. This planning approach was applied in four simulated cases with comparison to the plan according to RTOG 0848 contouring consensus guidelines. Raystation v4.5.1.14 was used for analyzing high throughput physics data.ResultsEighty-three patients with local recurrence were included from 305 postoperative pancreatic cancer patients who did not receive adjuvant radiotherapy. Thirty-one (37 %) patients did not have adjuvant therapy at all, 52 (63 %) patients undergone adjuvant chemotherapy alone. Spatial location of local failure was created. Most recurrences occurred near CA or SMA. CTV-90 was generated through expanding the combined SMA and CA contours by 30 mm right-lateral, 21 mm left-lateral, 20 mm anterior, 13 mm posterior, 10 mm superior, and 20 mm inferior. CTV-80, smaller in volume, was also created for simultaneous integrated boost. Through comparison and analysis of the simulated cases, the radiation volumes proposed were much smaller than those with RTOG 0848 contouring consensus guidelines (average volume: PTV-80 = 120 ml, PTV-90 = 220 ml, RTOG PTV = 490 ml). Accordingly, the organs at risk received less irradiation dose with the proposed CTV-90 and CTV-80.ConclusionsSmaller adjuvant radiotherapy CTVs targeting the high-risk local failure areas of postoperative pancreatic cancer were proposed, according to the three-dimensional spatial location of local recurrences. This may help to minimize radiation-related toxicities, achieve dose escalation, and finally reduce local recurrence.

Aims In patients with renal disease, high serum phosphate shows a relationship with cardiovascular risk. We speculate that high phosphate (HP) impairs arterial vasodilation via the endothelium and explore potential underlying mechanisms. Methods Isolated vessel relaxation, endothelial function, glomerular filtration rate (GFR), oxidative stress status and protein expression were assessed in HP diet mice. Mitochondrial function and protein expression were assessed in HP‐treated human umbilical vein endothelial cells (HUVECs). Results High phosphate (1.3%) diet for 12 weeks impaired endothelium‐dependent relaxation in mesenteric arteries, kidney interlobar arteries and afferent arterioles; reduced GFR and the blood pressure responses to acute administration of acetylcholine. The PPARα/LKB1/AMPK/eNOS pathway was attenuated in the endothelium of mesenteric arteries from HP diet mice. The observed vasodilatory impairment of mesenteric arteries was ameliorated by PPARα agonist WY‐14643. The phosphate transporter PiT‐1 knockdown prevented HP‐mediated suppression of eNOS activity by impeding phosphorus influx in HUVECs. Endothelium cytoplasmic and mitochondrial reactive oxygen species (ROS) were increased in HP diet mice. Moreover HP decreased the expression of mitochondrial‐related antioxidant genes. Finally, mitochondrial membrane potential and PGC‐1α expression were reduced by HP treatment in HUVECs, which was partly restored by AMPKα agonist. Conclusions HP impairs endothelial function by reducing NO bioavailability via decreasing eNOS activity and increasing mitochondrial ROS, in which the AMPK‐related signalling pathways may play a key role.