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Are fiducial markers useful surrogates when using respiratory gating to reduce motion of gastroesophageal junction tumors?

ABSTRACT: Radiation therapy (RT) is an integral component of the management of gastroesophageal junction (GEJ) tumors. We evaluated the use of implanted radiopaque fiducials as tumor surrogates to allow for more focal delivery of RT to these mobile tumors when using respiratory gating (RG) to reduce motion.We analyzed four-dimensional computed tomography scans of 20 GEJ patients treated with RG and assessed correlation between tumor and implanted fiducial motion over the whole respiratory cycle and within a clinically realistic gate around end-exhalation. We evaluated fiducial motion concordance in 11 patients with multiple fiducials.Gating reduced anterior-posterior (AP) and superior-inferior (SI) mean tumor and fiducial motions by over 50%. Fiducials and primary tumor motions were moderately correlated: R(2) for AP and SI linear fits to the entire group were 0.54 and 0.68, respectively, but the correlation had strong inter-patient variation. For all patients with multiple fiducials, relative in-gate displacements were below 3?mm; results were similar for eight of 11 patients over the whole cycle.Implanted fiducial and gross tumor volume (GTV) motions correlate well but the correlation is patient-specific and may be dependent on the location of the fiducials with respect to the GTV.

SUBMITTER: Liu F

PROVIDER: S-EPMC5016835 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature

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Are fiducial markers useful surrogates when using respiratory gating to reduce motion of gastroesophageal junction tumors?

Liu Fenghong F Ng Shu S Huguet Florence F Yorke Ellen D ED Mageras Gikas S GS Goodman Karyn A KA

Acta oncologica (Stockholm, Sweden) 20160506 8

<h4>Background</h4>Radiation therapy (RT) is an integral component of the management of gastroesophageal junction (GEJ) tumors. We evaluated the use of implanted radiopaque fiducials as tumor surrogates to allow for more focal delivery of RT to these mobile tumors when using respiratory gating (RG) to reduce motion.<h4>Material and methods</h4>We analyzed four-dimensional computed tomography scans of 20 GEJ patients treated with RG and assessed correlation between tumor and implanted fiducial mo ...[more]

PMID: 27152887

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Project description:The treatment of gastroesophageal junction tumors remains controversial due to confusion on whether they should be considered as primary esophageal or as gastric tumors. The incidence of these tumors with poor prognosis has increased, thus creating scientific interest on gastroesophageal cancers. Esophagogastric cancers are classified according to their location by Siewert, and the treatment of each type varies. We evaluated the prognostic factors and differences in clinicopathologic factors of patients with gastroesophageal junction tumor, who have been treated and followed-up in our clinics.We retrospectively analyzed 187 patients with gastroesophageal junction tumors who have been operated and treated in the Oncology Department between 2005 and 2014. The chi-square test was used to evaluate differences in clinicopathologic factors among Siewert groups I, II and III. Prognostic factors were analyzed by univariate and multivariate analysis.The median age of our patients was 62 years, and approximately 70% was male. Nineteen patients (10.2%) had Siewert I tumors, 40 (21.4%) II, and the remaining 128 (64.4%) had Siewert III tumors. Siewert III tumors were at more advanced pathologic and T stages. Preoperative chemoradiotherapy was mostly applied to Siewert group I patients. There was no difference between the 3 groups in terms of recurrence. While the median overall survival and 2-year overall survival rate were 26.6 months and 39.6%, the median disease free survival and disease free survival rates were 16.5 months and 30.1%, respectively. The N stage, pathologic stage, vascular invasion, lymphatic invasion, perineural invasion, surgical margin, and grade were associated with both overall survival and disease free survival, while pathologic stage and presence of recurrence were significant factors for overall survival. The median disease free survival for Siewert III tumors was 20 months, 11.3 month for Siewert I tumors, and 14 months for Siewert II tumors, but the finding was not statistically significant (p=0.08).Although gastroesophageal junction tumors were grouped according to their location and they exerted different clinicopathologic properties, their prognosis was similar.

Project description:BackgroundNeoadjuvant therapy for resectable gastric cancer/gastroesophageal junction tumors is progressing slowly. Although immunotherapy for advanced gastric cancer/gastroesophageal junction tumors has made great progress, the efficacy and safety of neoadjuvant immunotherapy for locally resectable gastric cancer/gastroesophageal junction tumors have not been clearly demonstrated. Here, we conducted a systematic review and meta-analysis to assess the efficacy and safety of neoadjuvant immunotherapy and advance the current research.MethodsOriginal articles describing the safety and efficacy of neoadjuvant immunotherapy for resectable gastric cancer/gastroesophageal junction tumors published up until October 15, 2023 were retrieved from PubMed, Embase, the Cochrane Library, and other major databases. The odds ratios (OR) and 95% confidence intervals (CIs) were calculated for heterogeneity and subgroup analysis.ResultsA total of 1074 patients from 33 studies were included. The effectiveness of neoadjuvant immunotherapy was mainly evaluated using pathological complete remission (PCR), major pathological remission (MPR), and tumor regression grade (TRG). Among the included patients, 1015 underwent surgical treatment and 847 achieved R0 resection. Of the patients treated with neoadjuvant immunotherapy, 24% (95% CI: 19%-28%) achieved PCR and 49% (95% CI: 38%-61%) achieved MPR. Safety was assessed by a surgical resection rate of 0.89 (95% CI: 85%-93%), incidence of ≥ 3 treatment-related adverse events (TRAEs) of 28% (95% CI: 17%-40%), and incidence of ≥ 3 immune-related adverse events (irAEs) of 19% (95% CI: 11%-27%).ConclusionNeoadjuvant immunotherapy, especially neoadjuvant dual-immunotherapy combinations, is effective and safe for resectable gastric/gastroesophageal junction tumors in the short term. Nevertheless, further multicenter randomized trials are required to demonstrate which combination model is more beneficial.Systematic review registrationhttps://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=358752, identifier CRD42022358752.

Project description:There is broad consensus on surgical resection being the backbone of curative therapy of gastric- and gastroesophageal junction carcinoma. Nevertheless, details on therapeutic approaches in addition to surgery, such as chemotherapy, radiotherapy or radiochemotherapy are discussed controversially; especially whether external beam radiotherapy should be applied in addition to chemotherapy and surgery is debated in both entities and differs widely between regions and centers. Early landmark trials such as the Intergroup-0116 and the MAGIC trial must be interpreted in the context of potentially insufficient lymph node resection. Despite shortcomings of both trials, benefits on overall survival by radiochemotherapy and adjuvant chemotherapy were confirmed in populations of D2-resected gastric cancer patients by Asian trials.Recent results on junctional carcinoma patients strongly suggest a survival benefit of neoadjuvant radiochemotherapy in curatively resectable patients. An effect of chemotherapy in the perioperative setting as given in the MAGIC study has been confirmed by the ACCORD07 trial for junctional carcinomas; however both the studies by Stahl et al. and the excellent outcome in the CROSS trial as compared to all other therapeutic approaches indicate a superiority of neoadjuvant radiochemotherapy as compared to perioperative chemotherapy in junctional carcinoma patients. Surgery alone without neoadjuvant or perioperative therapy is considered suboptimal in patients with locally advanced disease.In gastric carcinoma patients, perioperative chemotherapy has not been compared to adjuvant radiochemotherapy in a randomized setting. Nevertheless, the results of the recently published ARTIST trial and the Chinese data by Zhu and coworkers, indicate a superiority of adjuvant radiochemotherapy as compared to adjuvant chemotherapy in terms of disease free survival in Asian patients with advanced gastric carcinoma. The ongoing CRITICS trial is supposed to provide reliable conclusions about which therapy should be preferred in Western patients with gastric carcinoma. If radiotherapy is performed, modern approaches such as intensity-modulated radiotherapy and image guidance should be applied, as these methods reduce dose to organs at risk and provide a more homogenous coverage of planning target volumes.

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Are fiducial markers useful surrogates when using respiratory gating to reduce motion of gastroesophageal junction tumors?

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Are fiducial markers useful surrogates when using respiratory gating to reduce motion of gastroesophageal junction tumors?

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