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Objective:To retrospectively analyze the relationship between patterns of local recurrence and radiotherapy target dose after adjuvant radiotherapy for the pancreatic ductal adenocarcinoma(PDAC), aiming to provide reference for exploring reasonable target and dosage.Methods:Clinical data of 138 patients with T 1-4N 0-2M 0 PDAC who underwent adjuvant radiotherapy after radical resection from April 2012 to December 2020 were analyzed retrospectively. The influencing factors of local recurrence and the correlation between local recurrence site and radiotherapy target dose were analyzed. Results:The median follow-up time was 37.2 months. The median overall survival (mOS) was 29.9 months. The 5-year OS rate was 27.4%. And the median progression-free survival (mPFS) was 13.9 months. There were 24 cases of local recurrence (17.4%), and 10 cases of local recurrence complicated with distant metastasis (7.2%). The correlation between local recurrence site and radiotherapy target dose could be evaluated in 19 patients with complete clinical data. The first local recurrence occurred near the para-aortic (Ao), the celiac axis (CA) and the superior mesenteric artery (SMA) were 8, 5 and 4 cases, respectively. The radiotherapy doses of 8 patients with local recurrence only in the PTV field were above 45 Gy. There were 8 cases of local recurrence both in and out of the PTV field, including 3 cases with dose line between 40 and 52 Gy, 2 cases with dose line between 20 and 47.5 Gy, and 3 cases with dose line between 0.5 and 52.5 Gy. There were 3 cases of local recurrence out of the PTV field, and the dose line ranged from 0 to 20 Gy.Conclusions:The local recurrence rate of PDAC after radical surgery combined with postoperative radiotherapy is low, but a small number of patients have recurrence in the high-dose range of radiation field and regional recurrence out of the field. For these patients, it may be necessary to explore a more appropriate target dose and range for adjuvant radiotherapy.
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Objective To investigate the effect of enteral nutrition support via naso-jejunal tube in esopha-geal carcinoma patients treated with radiotheraphy.Methods 36 esophageal carcinoma patients were randomly assigned into enteral nutrition(EN)group,while 38 patients assigned to control group.All patients underwent defini-tion IMRT combined with weekly concurrent chemotherapy of paclitaxel-nedaplatin.The naso -jejunal tubes were bedside inserted by hand in EN group.Enteral nutrition support began the day after the tube insertion.The control group took food orally.Nutrition was assessed through body weight,BMI,lymphocyte,albumin,pre -albumin and hemoglobin.Treatment induced complications were recorded.Results The degree of nutritional reduction was lower in EN group and significantly different with the control group.The EN group underwent (4.5 ±1 .1 )cycles concurrent chemotherapy,the control group underwent (3.1 ±2.3)cycles concurrent chemotherapy(t=6.21,P=0.027).The hematotoxicity induced by chemoradiotherapy(CRT)was statistically severe in the control group(χ2 =24.64,P<0.01),while radiation esophagitis was similar between the two groups.Conclusion EN support via naso -jejunal tube in esophageal carcinoma patients treated with radiotheraphy may improve the nutritional status,alleviate CRT induced hematotoxicity,increase tolerance of CRT.
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Objective:To compare the dosimetric differences between volumetric modulated arc radiotherapy with RapidArc and fixed-field intensity modulation radiation therapy (IMRT) for nasopharyngeal carcinoma (NPC), and identify the techniques from which patients of different T stages can gain the maximum benefit. Methods:Sixty non-metastatic patients with NPC were randomly selected. According to the T staging of 2008 Chinese Classification, T1-T2 stage cases were observed in 20 of the 60 patients, whereas T3 and T4 stage cases were seen with 20 patients each. RapidArc and IMRT treatment plans were managed by the Eclipse treatment planning sys-tem of Varian Co., US. The dosimetry of the target volume coverage, organs at risk (OARs), monitor unit (MU) per second, and deliv-ery time were evaluated. Results:Both techniques reached the requirement of clinical treatment. The coverages of planning target vol-ume, conformity index, and homogeneity index were similar. However, the stratified analysis of T staging indicated that RapidArc plans led to an increased dose to the tumor target (P<0.05) and an improved homogeneity index (P=0.059) in the T4 stage cases. RapidArc al-lowed a statistical dose reduction to the OARs, including optic nerves, lens, temporal lobe, V20 of the parotids, larynx, and temporo-mandibular joint (P<0.05). In the T-stage stratified analysis, the D1%and Dmax of brain stem in T1-T3 stages were similar but statistical-ly low in T4 stage in the RapidArc group (P<0.05). Compared with those in IMRT group, the MUs and the delivery time in RapidArc group were reduced by 65%and 63%, respectively. Conclusion:Both RapidArc and IMRT attained the clinical requirement for NPC. RapidArc technique showed improvements in the OARs and reduction in MUs and delivery time. The target volume coverages were similar for T1-T3 stage. However, RapidArc delivered an increased dose to the tumor target in T4 stage cases, and the dose to OARs was reduced.