Development of a Margin Determination Framework for Tumor-Tracking Radiation Therapy With Intraoperatively Implanted Fiducial Markers

PurposeTo develop an internal target volume (ITV) margin determination framework (or decision-supporting framework) for treating multiple lung metastases using CyberKnife Synchrony with intraoperatively implanted fiducial markers (IIFMs). The feasibility of using non-ideally implanted fiducial markers (a limited number and/or far from a target) for tracking-based lung stereotactic ablative radiotherapy (SABR) was investigated.MethodsIn the developed margin determination framework, an optimal set of IIFMs was determined to minimize a tracking uncertainty-specific ITV (ITVtracking) margin (margin required to cover target-to-marker motion discrepancy), i.e., minimize the motion discrepancies between gross tumor volume (GTV) and the selected set of fiducial markers (FMs). The developed margin determination framework was evaluated in 17 patients with lung metastases. To automatically calculate the respiratory motions of the FMs, a template matching-based FM tracking algorithm was developed, and GTV motion was manually measured. Furthermore, during-treatment motions of the selected FMs were analyzed using log files and compared with those calculated using 4D CTs.ResultsFor 41 of 42 lesions in 17 patients (97.6%), an optimal set of the IIFMs was successfully determined, requiring an ITVtracking margin less than 5 mm. The template matching-based FM tracking algorithm calculated the FM motions with a sub-millimeter accuracy compared with the manual measurements. The patient respiratory motions during treatment were, on average, significantly smaller than those measured at simulation for the patient cohort considered.ConclusionUse of the developed margin determination framework employing CyberKnife Synchrony with a limited number of IIFMs is feasible for lung SABR.

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Potential dosimetric benefits of adaptive tumor tracking over the internal target volume concept for stereotactic body radiation therapy of pancreatic cancer

Radiation Oncology ◽

10.1186/s13014-017-0906-9 ◽

2017 ◽

Vol 12 (1) ◽

Cited By ~ 5

Author(s):

Konstantina Karava ◽

Stefanie Ehrbar ◽

Oliver Riesterer ◽

Johannes Roesch ◽

Stefan Glatz ◽

...

Keyword(s):

Pancreatic Cancer ◽

Radiation Therapy ◽

Stereotactic Body Radiation Therapy ◽

Target Volume ◽

Internal Target ◽

Internal Target Volume ◽

Stereotactic Body Radiation ◽

Tumor Tracking

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Cardiac-Sparing and Breast-Sparing Whole Lung Irradiation Using Intensity-Modulated Proton Therapy

International Journal of Particle Therapy ◽

10.14338/ijpt-20-00079.1 ◽

2021 ◽

Author(s):

Ru Xin Wong ◽

Jacqueline Faught ◽

Melissa Gargone ◽

William Myers ◽

Matthew Krasin ◽

...

Keyword(s):

Proton Therapy ◽

Planning Target Volume ◽

Pediatric Patients ◽

Lung Metastases ◽

Target Volume ◽

Internal Target Volume ◽

Intensity Modulated Proton Therapy ◽

Intensity Modulated ◽

Lung Irradiation ◽

Whole Lung Irradiation

Abstract Purpose Whole lung irradiation (WLI) is indicated for certain pediatric patients with lung metastases. This study investigated whether WLI delivered as intensity-modulated proton therapy (IMPT) could significantly spare the heart and breasts when compared with conventional WLI delivered with anteroposterior/posteroanterior photon fields and with intensity-modulated photon therapy (IMRT) WLI. Materials and Methods Conventional, IMRT, and IMPT plans were generated for 5 patients (aged 5-22 years). The prescription dose was 16.5 GyRBE in 1.5-GyRBE fractions. Conventional plans used 6-MV photons prescribed to the midline and a field-in-field technique to cover the planning target volume (the internal target volume [ITV] + 1 cm). IMRT plans used 6-MV photons with a 7-beam arrangement with dose prescribed to the planning target volume. IMPT plans used scenario-based optimization with 5% range uncertainty and 5-mm positional uncertainty to cover the ITV robustly. Monte Carlo dose calculation was used for all IMPT plans. Doses were compared with paired Student t test. Results The ITV Dmean was similar for the IMPT, conventional, and IMRT plans, but the IMPT plans had a lower Dmin and a higher Dmax at tissue interfaces than conventional plans (Dmean ratio: 0.96, P > .05; Dmin ratio: 0.9, P < .001; Dmax ratio: 1.1, P = .014). Dmeans for breast and heart substructures were lower with IMPT plans than with conventional/IMRT plans (heart ratios, 0.63:0.73; left ventricle ratios, 0.61:0.72; right ventricle ratios, 0.45:0.57; left atrium ratios, 0.79:0.85; right atrium ratios, 0.81:0.86; left breast ratios, 0.40:0.51; right breast ratio, 0.46:0.52; all P < .05). Conclusions IMPT resulted in comparable ITV coverage and lower mean doses to the heart and breasts when compared with other techniques. Whole lung irradiation delivered as IMPT warrants prospective evaluation in pediatric patients.

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Quantifying the Accuracy of Intrafractional Internal Target Volume Margin in Stereotactic Body Radiotherapy for Prostate Cancer Using CyberKnife Tumor Tracking System

International Journal of Radiation Oncology*Biology*Physics ◽

10.1016/j.ijrobp.2011.06.1561 ◽

2011 ◽

Vol 81 (2) ◽

pp. S874-S875

Author(s):

H. Yu ◽

C. Chen ◽

J. Tsai ◽

T. Chung

Keyword(s):

Prostate Cancer ◽

Stereotactic Body Radiotherapy ◽

Tracking System ◽

Target Volume ◽

Internal Target ◽

Internal Target Volume ◽

Tumor Tracking

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Proton Beam Therapy without Fiducial Markers Using Four-Dimensional CT Planning for Large Hepatocellular Carcinomas

Cancers ◽

10.3390/cancers10030071 ◽

2018 ◽

Vol 10 (3) ◽

pp. 71 ◽

Cited By ~ 2

Author(s):

Satoshi Shibata ◽

Shigeyuki Takamatsu ◽

Kazutaka Yamamoto ◽

Miu Mizuhata ◽

Sayuri Bou ◽

...

Keyword(s):

Proton Beam ◽

Treatment Protocol ◽

Progression Free Survival ◽

Proton Beam Therapy ◽

Target Volume ◽

Tumor Control ◽

Fiducial Markers ◽

Internal Target Volume ◽

4D Ct ◽

Hepatocellular Carcinomas

We evaluated the effectiveness and toxicity of proton beam therapy (PBT) for hepatocellular carcinomas (HCC) >5 cm without fiducial markers using four-dimensional CT (4D-CT) planning. The subjects were 29 patients treated at our hospital between March 2011 and March 2015. The median total dose was 76 Cobalt Gray Equivalents (CGE) in 20 fractions (range; 66–80.5 CGE in 10–32 fractions). Therapy was delivered with end-expiratory phase gating. An internal target volume (ITV) margin was added through the analysis of respiratory movement with 4D-CT. Patient age ranged from 38 to 87 years (median, 71 years). Twenty-four patients were Child–Pugh class A and five patients were class B. Tumor size ranged from 5.0 to 13.9 cm (median, 6.9 cm). The follow-up period ranged from 2 to 72 months (median; 27 months). All patients completed PBT according to the treatment protocol without grade 4 (CTCAE v4.03 (draft v5.0)) or higher adverse effects. The two-year local tumor control (LTC), progression-free survival (PFS), and overall survival (OS) rates were 95%, 22%, and 61%, respectively. The LTC was not inferior to that of previous reports using fiducial markers. Respiratory-gated PBT with 4D-CT planning without fiducial markers is a less invasive and equally effective treatment for large HCCs as PBT with fiducial markers.

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Role of Thermal Ablation in Colorectal Cancer Lung Metastases

Cancers ◽

10.3390/cancers13040908 ◽

2021 ◽

Vol 13 (4) ◽

pp. 908

Author(s):

Alexandre Delpla ◽

Thierry de Baere ◽

Eloi Varin ◽

Frederic Deschamps ◽

Charles Roux ◽

...

Keyword(s):

Colorectal Cancer ◽

Prognostic Factors ◽

Thermal Ablation ◽

Medical Oncology ◽

Pulmonary Metastases ◽

Lung Metastases ◽

Stereotactic Ablative Radiotherapy ◽

Chest Drainage ◽

Results Of Surgery

Background: Consensus guidelines of the European Society for Medical Oncology (ESMO) (2016) provided recommendations for the management of lung metastases. Thermal ablation appears as a tool in the management of these secondary pulmonary lesions, in the same manner as surgical resection or stereotactic ablative radiotherapy (SABR). Methods: Indications, technical considerations, oncological outcomes such as survival (OS) or local control (LC), prognostic factors and complications of thermal ablation in colorectal cancer lung metastases were reviewed and put into perspective with results of surgery and SABR. Results: LC rates varied from 62 to 91%, with size of the metastasis (<2 cm), proximity to the bronchi or vessels, and size of ablation margins (>5 mm) as predictive factors of LC. Median OS varied between 33 and 68 months. Pulmonary free disease interval <12 months, positive carcinoembryonic antigen, absence of neoadjuvant chemotherapy and uncontrolled extra-pulmonary metastases were poor prognostic factors for OS. While chest drainage for less than 48 h was required in 13 to 47% of treatments, major complications were rare. Conclusions: Thermal ablation of a selected subpopulation of patients with colorectal cancer lung metastases is safe and can provide excellent LC and delay systemic chemotherapy.

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