几何不确定性鲁棒优化在肝癌立体定向放疗中的应用

目的:分析基于几何不确定性的鲁棒优化计划对肝癌立体定向放疗（SBRT）剂量分布的影响。方法:选取12例肝癌SBRT患者，对每例制作3个调强计划:①基于PTV（ITV-PTV 5 mm）的常规优化（PTV-Based Plan）；②基于ITV非均匀几何不确定性（本中心计算的不确定性值:进出方向7 mm，左右和前后方向4 mm）的鲁棒优化（Robust Planactual）；③基于ITV均匀5 mm几何不确定性的鲁棒优化（Robust Plan5 mm）。所有计划都以95%的PTV满足处方剂量作为目标，以等中心均匀偏移4、5、7 mm计算扰动剂量评估鲁棒性。结果:计划①②③的均匀性指数（HI）分别为0.083±0.027、0.099±0.035、0.096±0.026，不具有统计学意义；计划①②③的适形性指数（CI）分别为0.98±0.02、1.02±0.05、1.00±0.04，计划②③相对于计划①的CI具有统计学意义。计划③的正常肝组织平均受量和V2500相对于计划①②分别下降了4.1%、2.5%和5.4%、3.0%，且具有统计学意义（P=0.034、P=0.021和P=0.004、P=0.004），计划②相对于计划①的正常肝组织平均受量和V2500不具有统计学意义（P=0.308和P=0.182），但下降了1.6%和2.5%。对于其鲁棒性，计划②③的5 mm-D99%、5 mm-D98%、5 mm-D95%的剂量-体积直方图带宽（DVHBW）差值相对于计划①更小，随着摆位不确定度的增大，其DVHBW差值越大。结论:在肝脏SBRT治疗中，采用鲁棒优化能够提高靶区剂量分布质量，即使在摆位不确定度有所增加的情况下，仍可以保证ITV的剂量覆盖同时不增加正常组织的照射剂量。     

Global colorectal cancer research, 2007-2021: Outputs and funding

The purpose of this study was to provide an evidence base for colorectal cancer research activity that might influence policy, mainly at the national level. Improvements in healthcare delivery have lengthened life expectancy, but within a situation of increased cancer incidence. The disease burden of CRC has risen significantly, particularly in Africa, Asia and Latin America. Research is key to its control and reduction, but few studies have delineated the volume and funding of global research on CRC. We identified research papers in the Web of Science (WoS) from 2007 to 2021, and determined the contributions of the leading countries, the research domains studied, and their sources of funding. We identified 62 716 papers, representing 5.7% of all cancer papers. This percentage was somewhat disproportionate to the disease burden (7.7% in 2015), especially in Eastern Europe. International collaboration increased over the time period in almost all countries except in China. Genetics, surgery and prognosis were the leading research domains. However, research on palliative care and quality-of-life in CRC was lacking. In Western Europe, the main funding source was the charity sector, particularly in the UK, but in most other countries government played the leading role, especially in China and the USA. There was little support from industry. Several Asian countries provided minimal contestable funding, which may have reduced the impact of their CRC research. Certain countries must perform more CRC research overall, especially in domains such as screening, palliative care and quality-of-life. The private-non-profit sector should be an alternative source of support.     

Recurrent aseptic liver abscesses in a patient with Crohn’s disease: True infection or a Crohn’s flare?

A liver abscess is identified as a rare extraintestinal manifestation of Crohn’s disease, with an incidence of approximately 150 in 100,000 patients with this condition. In many of these patients, infectious causes are identified, and the patient’s condition is often noted to improve with antibiotics. An aseptic abscess (AA) is an increasingly recognized entity, especially in patients with inflammatory bowel disease, where repetitive evaluations to identify the infectious cause are futile. The average age of diagnosis for an AA is 29 years. The most common site is the spleen, followed by the lymph nodes and then the liver. In this study, we present a unique case of extensive aseptic liver abscesses extending into the pleural cavity in a young patient with Crohn’s disease.     

Phase 0 Study of Vandetanib-Eluting Radiopaque Embolics as a Preoperative Embolization Treatment in Patients with Resectable Liver Malignancies

PurposeTo assess the safety and tolerability of a vandetanib-eluting radiopaque embolic (BTG-002814) for transarterial chemoembolization (TACE) in patients with resectable liver malignancies.Materials and MethodsThe VEROnA clinical trial was a first-in-human, phase 0, single-arm, window-of-opportunity study. Eligible patients were aged ≥18 years and had resectable hepatocellular carcinoma (HCC) (Child-Pugh A) or metastatic colorectal cancer (mCRC). Patients received 1 mL of BTG-002814 transarterially (containing 100 mg of vandetanib) 7–21 days prior to surgery. The primary objectives were to establish the safety and tolerability of BTG-002814 and determine the concentrations of vandetanib and the N-desmethyl vandetanib metabolite in the plasma and resected liver after treatment. Biomarker studies included circulating proangiogenic factors, perfusion computed tomography, and dynamic contrast-enhanced magnetic resonance imaging.ResultsEight patients were enrolled: 2 with HCC and 6 with mCRC. There was 1 grade 3 adverse event (AE) before surgery and 18 after surgery; 6 AEs were deemed to be related to BTG-002814. Surgical resection was not delayed. Vandetanib was present in the plasma of all patients 12 days after treatment, with a mean maximum concentration of 24.3 ng/mL (standard deviation ± 13.94 ng/mL), and in resected liver tissue up to 32 days after treatment (441–404,000 ng/g). The median percentage of tumor necrosis was 92.5% (range, 5%–100%). There were no significant changes in perfusion imaging parameters after TACE.ConclusionsBTG-002814 has an acceptable safety profile in patients before surgery. The presence of vandetanib in the tumor specimens up to 32 days after treatment suggests sustained anticancer activity, while the low vandetanib levels in the plasma suggest minimal release into the systemic circulation. Further evaluation of this TACE combination is warranted in dose-finding and efficacy studies.