scholarly journals Technical Assessment of an Automated Treatment Planning on Dose Escalation of Pancreas Stereotactic Body Radiotherapy

2019 ◽  
Vol 18 ◽  
pp. 153303381985152 ◽  
Author(s):  
Shuo Wang ◽  
Dandan Zheng ◽  
Chi Lin ◽  
Yu Lei ◽  
Vivek Verma ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
Treatment Planning ◽  
Dose Escalation ◽  
Stereotactic Body Radiotherapy ◽  
Locally Advanced ◽  
Advanced Pancreatic Cancer ◽  
Intensity Modulated Radiotherapy ◽  
Intensity Modulated ◽  
Percentage Volume ◽  
Prescription Dose

Background: Stereotactic body radiotherapy has been suggested to provide high rates of local control for locally advanced pancreatic cancer. However, the close proximity of highly radiosensitive normal tissues usually causes the labor-intensive planning process and may impede further escalation of the prescription dose. Purpose: The present study aims to evaluate the consistency and efficiency of Pinnacle Auto-Planning for pancreas stereotactic body radiotherapy with original prescription and escalated prescription. Methods: Twenty-four patients with pancreatic cancer treated with stereotactic body radiotherapy were studied retrospectively. The prescription is 40 Gy over 5 consecutive fractions. Most of patients (n = 21) also had 3 other different dose-level targets (6 Gy/fraction, 5 Gy/fraction, and 4 Gy/fraction). Two types of plans were generated by Pinnacle Auto-Planning with the original prescription (8 Gy/fraction, 6 Gy/fraction, 5 Gy/fraction, and 4 Gy/fraction) and escalated prescription (9 Gy/fraction, 7 Gy/fraction, 6 Gy/fraction, and 5 Gy/fraction), respectively. The same Auto-Planning template, including beam geometry, intensity-modulated radiotherapy objectives and intensity-modulated radiotherapy optimization parameters, were utilized for all the auto-plans in each prescription group. The intensity-modulated radiotherapy objectives do not include any manually created structures. Dosimetric parameters including percentage volume of PTV receiving 100% of the prescription dose, percentage volume of PTV receiving 93% of the prescription dose, and consistency of the dose-volume histograms of the target volumes were assessed. Dmax and D1 cc of highly radiosensitive organs were also evaluated. Results: For all the pancreas stereotactic body radiotherapy plans with the original or escalated prescriptions, auto-plans met institutional dose constraints for critical organs, such as the duodenum, small intestine, and stomach. Furthermore, auto-plans resulted in acceptable planning target volume coverage for all targets with different prescription levels. All the plans were generated in a one-attempt manner, and very little human intervention is necessary to achieve such plan quality. Conclusions: Pinnacle3 Auto-Planning consistently and efficiently generate acceptable treatment plans for multitarget pancreas stereotactic body radiotherapy with or without dose escalation and may play a more important role in treatment planning in the future.

scholarly journals Intensity-Modulated and Image-Guided Radiotherapy in Patients with Locally Advanced Inoperable Pancreatic Cancer after Preradiation Chemotherapy

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
M. Sinn ◽  
R. Ganeshan ◽  
R. Graf ◽  
U. Pelzer ◽  
J. M. Stieler ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
Overall Survival ◽  
Locally Advanced ◽  
Advanced Pancreatic Cancer ◽  
Intensity Modulated Radiotherapy ◽  
Image Guided Radiotherapy ◽  
Image Guided ◽  
Intensity Modulated ◽  
Kaplan Meier ◽  
Median Dosage

Background. Radiotherapy (RT) in patients with pancreatic cancer is still a controversial subject and its benefit in inoperable stages of locally advanced pancreatic cancer (LAPC), even after induction chemotherapy, remains unclear. Modern radiation techniques such as image-guided radiotherapy (IGRT) and intensity-modulated radiotherapy (IMRT) may improve effectiveness and reduce radiotherapy-related toxicities.Methods. Patients with LAPC who underwent radiotherapy after chemotherapy between 09/2004 and 05/2013 were retrospectively analyzed with regard to preradiation chemotherapy (PRCT), modalities of radiotherapy, and toxicities. Progression-free (PFS) and overall survival (OS) were estimated by Kaplan-Meier curves.Results. 15 (68%) women and 7 men (median age 64 years; range 40–77) were identified. Median duration of PRCT was 11.1 months (range 4.3–33.0). Six patients (27%) underwent conventional RT and 16 patients (73%) advanced IMRT and IGRT; median dosage was 50.4 (range 9–54) Gray. No grade III or IV toxicities occurred. Median PFS (estimated from the beginning of RT) was 5.8 months, 2.6 months in the conventional RT group (conv-RT), and 7.1 months in the IMRT/IGRT group (P=0.029); median OS was 11.0 months, 4.2 months (conv-RT), and 14.0 months (IMRT/IGRT);P=0.141. Median RT-specific PFS for patients with prolonged PRCT>9 months was 8.5 months compared to 5.6 months for PRCT<9 months (P=0.293). This effect was translated into a significantly better median RT-specific overall survival of patients in the PRCT>9 months group, with 19.0 months compared to 8.5 months in the PRCT  <  9 months group (P=0.049).Conclusions. IGRT and IMRT after PRCT are feasible and effective options for patients with LAPC after prolonged preradiation chemotherapy.

Role of Radiotherapy and Newer Techniques in the Treatment of GI Cancers

2015 ◽  
Vol 33 (16) ◽  
pp. 1737-1744 ◽  
Author(s):  
Carla Hajj ◽  
Karyn A. Goodman
Keyword(s):  
Stereotactic Body Radiotherapy ◽  
Imaging Techniques ◽  
Multidisciplinary Treatment ◽  
Locally Advanced ◽  
Advanced Pancreatic Cancer ◽  
Intensity Modulated Radiotherapy ◽  
Radiotherapy Planning ◽  
Intensity Modulated ◽  
Gi Cancers

The role of radiotherapy in multidisciplinary treatment of GI malignancies is well established. Recent advances in imaging as well as radiotherapy planning and delivery techniques have made it possible to target tumors more accurately while sparing normal tissues. Intensity-modulated radiotherapy is an advanced method of delivering radiation using cutting-edge technology to manipulate beams of radiation. The role of intensity-modulated radiotherapy is growing for many GI malignancies, such as cancers of the stomach, pancreas, esophagus, liver, and anus. Stereotactic body radiotherapy is an emerging treatment option for some GI tumors such as locally advanced pancreatic cancer and primary or metastatic tumors of the liver. Stereotactic body radiotherapy requires a high degree of confidence in tumor location and subcentimeter accuracy of the delivered dose. New image-guided techniques have been developed to overcome setup uncertainties at the time of treatment, including real-time imaging on the linear accelerator. Modern imaging techniques have also allowed for more accurate pretreatment staging and delineation of the primary tumor and involved sites. In particular, magnetic resonance imaging and positron emission tomography scans can be particularly useful in radiotherapy planning and assessing treatment response. Molecular biomarkers are being investigated as predictors of response to radiotherapy with the intent of ultimately moving toward using genomic and proteomic determinants of therapeutic strategies. The role of all of these new approaches in the radiotherapeutic management of GI cancers and the evolving role of radiotherapy in these tumor sites will be highlighted in this review.

scholarly journals A92 DOSE ESCALATION STUDY OF CYBERKNIFE® BOOST IN UNRESECTABLE LOCALLY ADVANCED PANCREATIC CANCER

2020 ◽  
Vol 3 (Supplement_1) ◽  
pp. 107-108
Author(s):  
J Quinlan ◽  
J Pantarotto ◽  
K Dennis ◽  
A Chatterjee
Keyword(s):  
Pancreatic Cancer ◽  
Radiation Dose ◽  
Dose Escalation ◽  
Stereotactic Body Radiotherapy ◽  
Locally Advanced ◽  
Advanced Pancreatic Cancer ◽  
Locally Advanced Pancreatic Cancer ◽  
Treatment Technique ◽  
Conventional Radiotherapy ◽  
Locally Advanced Pancreatic Carcinoma

Abstract Background Pancreatic cancer is the 4th deadliest cancer in Canada, with an overall 5-year survival of only 6%. Every year, approximately 4000 Canadians are diagnosed with pancreatic cancer, and only 10–15% of these patients have surgically resectable disease. No satisfactory treatment exists for patients with inoperable locally advanced pancreatic carcinoma. The best survival has been achieved using a combination of chemotherapy and radiotherapy. Conventional radiotherapy has inadequate local disease control as the therapeutic radiation dose to the tumour is limited by the sensitivities of surrounding tissues. Stereotactic body radiotherapy (SBRT) is a minimally invasive treatment technique that allows for ultra-high doses of radiation to be delivered to small areas. The CyberKnife® Robotic Radiosurgery System is a radiation unit designed to deliver SBRT. Fiducial markers placed by endoscopic ultrasound help direct the radiotherapy. It is hypothesized that a higher overall dose of radiation will result in higher rates of local control, and potentially improved survival. Aims The goal of this study is to establish the safety and feasibility of using stereotactic body radiotherapy boost technique via CyberKnife in treating unresectable locally advanced pancreatic cancer, as well as to determine the maximal tolerable radiation dose (MTD) of the SBRT boost that can be safely delivered. Methods This is a prospective single-arm, single-institution phase I Time-to-event Continual Reassessment Methodology (TITE-CRM) radiation dose escalation trial. This study enrolled patients aged 18–84 with pathologically confirmed pancreatic cancer who were determined to have surgically unresectable disease, with an ECOG ≤2. These patients were treated with SBRT prior to starting conventional radiotherapy, which consisted of a total dose of 45 Gy in 25 fractions over 5 weeks. Results Between 2012 and 2018, a total of 11 patients met the eligibility criteria of this study. Their ages ranged from 61 to 84 with a mean of 71.5 years, and they were 64% (7/11) male. At the time of this analysis, 10 of the 11 patients had passed away. The mean and median survival times were 413 days and 313 days, respectively. Three of the patients had significant complications attributed to the radiotherapy, 2 gastric outlet obstructions and 1 deep duodenal ulcer. The doses used ranged from 21 Gy in 3 fractions to 50 Gy in 5 fractions. Conclusions This phase 1, single arm study demonstrates that stereotactic body radiotherapy in the treatment of locally advanced, unresectable pancreatic cancer is technically feasible. When combined with conventional radiotherapy, this therapy is generally well tolerated, and can effectively deliver higher doses of radiation to pancreatic malignancies. Doses up to 50 Gy in 5 fractions were tolerated, with the most common dose being 21 Gy in 3 fractions. Funding Agencies National Pancreatic Cancer Canada Foundation

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