Benefit of replacing the Sigma-60 by the Sigma-Eye applicator. A Monte Carlo-based uncertainty analysis.

Strahlenther Onkol

Department of Radiation Oncology, Erasmus MC - Daniel den Hoed, Groene Hilledijk 301, 3008 AE, Rotterdam, The Netherlands.

Published: January 2013

Background And Purpose: To investigate the clinical benefit of replacing the BSD-2000 Sigma-60 with the Sigma-Eye applicator, taking into account effects of uncertainties in tissue and water bolus parameters.

Patients And Methods: For 20 patients, specific absorption rate (SAR) and temperature distributions were calculated and optimized, based on computed tomography (CT) scans in treatment position. The impact of uncertainties on predicted distributions was studied using a Monte Carlo uncertainty assessment.

Results: Replacing the Sigma-60 by the Sigma-Eye applicator resulted in a higher SAR in the tumor [on average a decrease of the hotspot tumor quotient (HTQ) by 24%; p < 0.001], and higher temperatures (T90: +0.4°C, p < 0.001; T50: +0.6°C, p < 0.001) using literature values and SAR optimization. When temperature optimization (T90) was used, a larger average increase was found (T90: +0.7°C, p < 0.001; T50: +0.8°C, p < 0.001). When taking into account uncertainties, a decrease of 23% in median HTQ (p < 0.001) and an increase in T50 and T90 of 0.4°C (p < 0.001) could be demonstrated.

Conclusion: Based on this uncertainty analysis, significant and clinically relevant improvements in HTQ and tumor temperature were achieved when replacing the Sigma-60 by the Sigma-Eye applicator.

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00066-012-0241-xDOI Listing

Publication Analysis

Top Keywords

sigma-60 sigma-eye
12
sigma-eye applicator
12
benefit replacing
8
replacing sigma-60
8
applicator monte
4
monte carlo-based
4
carlo-based uncertainty
4
uncertainty analysis
4
analysis background
4
background purpose
4

Similar Publications

Article Synopsis
  • Hyperthermia treatment's effectiveness relies on achieving specific temperatures in targeted areas, requiring systems to provide controlled and conformal heating.
  • The study involved six European institutions testing BSD-Sigma 60 and Sigma Eye devices, measuring thermal distribution after heating with a total power of 1000 watts in standardized phantoms.
  • Results indicated that most applicators achieved the desired temperature increase, with minor deviations in focus location and symmetry, leading to proposed minimum acceptable values for quality metrics and recommendations for future quality assurance in hyperthermia applications.
View Article and Find Full Text PDF

Intravenous chemotherapy plus abdominal locoregional hyperthermia is explored as a noninvasive alternative to hyperthermic intraperitoneal chemotherapy (HIPEC) in treatment of peritoneal carcinomatosis (PC). First clinical results demonstrate feasibility, but survival data show mixed results and for pancreatic and gastric origin results are not better than expected for chemotherapy alone. In this study, computer simulations are performed to compare the effectiveness of peritoneal heating for five different locoregional heating systems.

View Article and Find Full Text PDF

Background: Peritoneal carcinomatosis occurs in different cancer subtypes and is associated with a dismal prognosis. Some doubts remain whether the whole abdomen can be treated by regional hyperthermia, therefore we analyzed feasibility conducting a pilot study.

Methods: A simulation of the abdominopelvic heat distribution in 11 patients with peritoneal carcinomatosis was done using the HyperPlan software and the SIGMA-60 and SIGMA-Eye applicators.

View Article and Find Full Text PDF

Benefit of replacing the Sigma-60 by the Sigma-Eye applicator. A Monte Carlo-based uncertainty analysis.

Strahlenther Onkol

January 2013

Department of Radiation Oncology, Erasmus MC - Daniel den Hoed, Groene Hilledijk 301, 3008 AE, Rotterdam, The Netherlands.

Background And Purpose: To investigate the clinical benefit of replacing the BSD-2000 Sigma-60 with the Sigma-Eye applicator, taking into account effects of uncertainties in tissue and water bolus parameters.

Patients And Methods: For 20 patients, specific absorption rate (SAR) and temperature distributions were calculated and optimized, based on computed tomography (CT) scans in treatment position. The impact of uncertainties on predicted distributions was studied using a Monte Carlo uncertainty assessment.

View Article and Find Full Text PDF

Purpose: To investigate whether one can replace the Sigma-60 with the Sigma-Eye applicator (or vice versa) during a deep hyperthermia treatment series without a loss in quality of the treatment.

Patients And Methods: Hyperthermia data of all 48 patients with locally advanced cervical cancer who were treated with both applicators were analysed. In this study no use was made of the longitudinal SAR steering option of the Sigma-Eye.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!