scholarly journals Conformal Radiotherapy Facilitates the Delivery of Concurrent Chemotherapy and Radiotherapy: A Case of Primitive Neuroectodermal Tumour of the Chest Wall

Sarcoma ◽  
2000 ◽  
Vol 4 (3) ◽  
pp. 129-133 ◽  
Author(s):  
C. E. Coles ◽  
N. Twyman ◽  
H. M. Earl ◽  
N. G. Burnet
Keyword(s):  
Chest Wall ◽  
Organs At Risk ◽  
Conformal Radiotherapy ◽  
Target Volume ◽  
Concurrent Chemotherapy ◽  
Radiotherapy Planning ◽  
Primitive Neuroectodermal Tumour ◽  
Normal Tissues ◽  
Neuroectodermal Tumour ◽  
Red Marrow

We illustrate the principle of conformal radiotherapy by discussing the case of a patient with a primitive neuroectodermal tumour of the chest wall. Recent advances in radiotherapy planning enable precise localization of the planning target volume (PTV) and normal organs at risk of irradiation. Customized blocks are subsequently designed to produce a treatment field that ‘conforms’ to the PTV. The use of conformal radiotherapy (CRT) in this case facilitated the delivery of concurrent chemotherapy and radiotherapy by significantly reducing the volume of red marrow irradiated.The lack of acute and late toxicities was attributed to optimal exclusion of normal tissues from the treatment field, made possible by CRT.

A dosimetric comparison of craniospinal irradiation using TomoDirect radiotherapy, TomoHelical radiotherapy and 3D conventional radiotherapy

2017 ◽  
Vol 16 (4) ◽  
pp. 391-402
Author(s):  
Shirley W. S. Tsang ◽  
Mark Collins ◽  
Jacky T. L. Wong ◽  
George Chiu
Keyword(s):  
Organs At Risk ◽  
Intensity Modulated Radiotherapy ◽  
Conformal Radiotherapy ◽  
Target Volume ◽  
Craniospinal Irradiation ◽  
Conventional Radiotherapy ◽  
Biological Damage ◽  
Dose Volume Histograms ◽  
Normal Tissues ◽  
Dose Volume

AbstractAimThe purpose of this study was to dosimetrically compare TomoDirect, TomoHelical and linear accelerator-based 3D-conformal radiotherapy (Linac-3DCRT) for craniospinal irradiation (CSI) in the treatment of medulloblastoma.MethodsFive CSI patients were replanned with Linac-3DCRT, TomoHelical, TomoDirect-3DCRT and TomoDirect-intensity-modulated radiotherapy (IMRT). Dose of 36 Gy in 20 fractions was prescribed to the planning target volume (PTV). Homogeneity index (HI), non-target integral dose (NTID), dose–volume histograms, organs-at-risk (OARs)Dmax,Dmeanand treatment times were compared.ResultsTomoHelical achieved the best PTV homogeneity compared with Linac-3DCRT, TomoDirect-3DCRT and TomoDirect-IMRT (HI of 3·6 versus 20·9, 8·7 and 9·4%, respectively). TomoDirect-IMRT achieved the lowest NTID compared with TomoDirect-3DCRT, TomoHelical and Linac-3DCRT (141 J versus 151 J, 181 J and 250 J), indicating least biological damage to normal tissues. TomoHelical plans achieved the lowestDmaxin all organs except the breasts, and lowestDmeanfor most OARs, except in laterally situated OARs, where TomoDirect triumphed. Beam-on time was longest for TomoHelical, followed by TomoDirect and Linac-3DCRT.FindingsTomoDirect has the potential to lower NTID and shorten treatment times compared with TomoHelical. It reduces PTV inhomogeneity and better spares OARs compared with Linac-3DCRT. Therefore, TomoDirect may be a CSI treatment alternative to TomoHelical and in place of Linac-3DCRT.

Technical illustration of Volumetric arc conformal radiotherapy planning in a case of paratesticular sarcoma

2021 ◽  
pp. 1-6
Author(s):  
Anil Gupta ◽  
Rambha Pandey ◽  
Seema Sharma ◽  
Vivek Ghosh ◽  
Ekta Dhamija ◽  
...  
Keyword(s):  
Organs At Risk ◽  
Target Volume ◽  
Radiotherapy Planning ◽  
Current Evidence ◽  
Lower Grade ◽  
Malignant Tumours ◽  
Target Volume Delineation ◽  
Volume Delineation ◽  
Delivery Technique ◽  
Technical Illustration

Abstract Introduction: Paratesticular sarcoma are extremely rare malignant tumours. Unlike other sites, they tend to be lower grade and have higher propensity of lymphatic spread. They tend to fail locally and occasionally in the regional lymph nodes. In the absence of target volume delineation guidelines and technical illustration of conformal planning, we have made an attempt to illustrate conformal planning methodology and define target volume based on current evidence in a case of paratesticular sarcoma. Methods: We are presenting a case of 62-year-old male who presented with 15-cm scrotal swelling and underwent high inguinal orchidectomy with ligation of spermatic cord. Histopathology presented a well-differentiated leiomyosarcoma of epididymis. Post-operative radiotherapy target volume included the tumour bed, ipsilateral inguinal nodes and lower pelvic nodes as the clinical target volume. Conclusion: Adjuvant radiotherapy using advanced delivery technique such as volumetric arc technique can provide good dose distribution with good sparing of organs at risk. The downside of conformal radiation delivery is that it is a resource-intensive and has no established target volume delineation guidelines.

Diagnostic imaging of primitive neuroectodermal tumour of the chest wall (Askin tumour)

1998 ◽  
Vol 28 (9) ◽  
pp. 697-702 ◽  
Author(s):  
G. Sallustio ◽  
Tommaso Pirronti ◽  
Anna Lasorella ◽  
Luigi Natale ◽  
Antonio Bray ◽  
...  
Keyword(s):  
Diagnostic Imaging ◽  
Chest Wall ◽  
Primitive Neuroectodermal Tumour ◽  
Neuroectodermal Tumour

Proton reirradiation of locally recurrent pancreatic and ampullary adenocarcinomas.

2013 ◽  
Vol 31 (4_suppl) ◽  
pp. 317-317 ◽  
Author(s):  
John Peter Plastaras ◽  
Abigail Berman ◽  
Smith Apisarnthanarax ◽  
Stefan Both ◽  
Kristi Varillo ◽  
...  
Keyword(s):  
Acute Toxicity ◽  
Tissue Injury ◽  
Target Volume ◽  
Ampullary Cancer ◽  
Concurrent Chemotherapy ◽  
Ampullary Adenocarcinoma ◽  
Normal Tissues ◽  
Volumetric Arc Therapy ◽  
Locally Recurrent

317 Background: Local recurrences of pancreatic and ampullary cancer can be painful and cause significant morbidity. Their treatment after resection and chemoradiation is particularly challenging. A second course of radiotherapy (RT) in a previously radiated field carries the risk of RT-induced tissue injury. Proton therapy (PRT) may offer an advantage in the reirradiation setting due to the lack of exit dose and potential sparing of normal tissues. Methods: Between 2/2011 and 8/2012, 10 adult patients (pts) with locally recurrent pancreatic or ampullary malignancies in or near prior treatment fields began reirradiation. Toxicity was graded according to the CTC v4.0. Acute toxicity was defined within 90 days from start of PRT. Results: Median follow-up was 8.2 months (1.1-19.1) from the start of retreatment and 15 months (2.4-27.8) from the development of local recurrence. Mean age was 67 (54-75). Nine of the pts had pancreatic adenocarcinoma and 1 had ampullary adenocarcinoma. Median clinical target volume size was 86.4 cc (15-236). Nine received concurrent 5-fluorouracil or capecitabine-based chemotherapy. The median total dose was 59.4 Gy(RBE)(45-59.4); all pts were treated with PRT exclusively, except for one pt who was treated with 36% photon volumetric arc therapy. The median prior dose was 50.4 Gy (30-59.4). The median interval between RT courses was 34 months (17-461). Nine pts had Grade 2 and 1 had only Grade 1 non-hematologic acute toxicity. No Grade 2 or higher non-hematologic RT-related toxicities were observed after 90 days from the start of RT. Five pts developed metastatic disease at a median of 7.4 months (4.8-13.2) after starting RT, 1 of whom died at 5.3 months. One pt developed progressive regional (paraaortic) disease inferior to the fields while on treatment and was stopped early at 45 Gy. One pt developed a regional metastasis (porta hepatis) outside of the retreated volume. The other 8 pts were controlled locally within the retreated fields. Conclusions: Reirradiation of pancreatic/ampullary cancers with PRT and concurrent chemotherapy has minimal acute toxicity and encouraging short-term local control. Further follow-up on these pts is needed to assess the long-term morbidity and utility of PRT reirradiation. Clinical trial information: NCT01126476.

scholarly journals Analysis of Geometric and Dosimetric Effects of Bra Application to Support Large or Pendulous Breasts During Radiotherapy Planning: A Retrospective Single-Center Study

2021 ◽  
Vol 20 ◽  
pp. 153303382110279
Author(s):  
So Hyun Park ◽  
Jinhyun Choi
Keyword(s):  
Clinical Target Volume ◽  
Organs At Risk ◽  
Target Volume ◽  
Radiotherapy Planning ◽  
Homogeneity Index ◽  
Breast Volume ◽  
Breast Cancer Patients ◽  
Single Center Study ◽  
Radiotherapy Field ◽  
Dose Reductions

Purpose: To evaluate geometric and dosimetric effects of bra application during radiotherapy planning for breast cancer patients with large and pendulous breasts. Materials and Methods: Twenty patients with chest sizes >38 inches between April 2019 and July 2019 underwent radiotherapy planning with and without a radiation bra (Chabner XRT®). Geometric and dosimetric parameters included the breast volume, superior-inferior (SI) distance, separation (S) as the distance of the longest diameter of the clinical target volume (CTV), conformity number (CN), and homogeneity index (HI) of CTV. The organs at risk (OARs) were defined as the lungs, heart, and liver. Results: The use of the radiation bra provided mean changes of −0.51 cm for S, −1.45 cm for SI, and −61.18 cc for breast volume (all P < 0.05). Breast volume was correlated with bra-related changes in cross diameter (r = 0.641, P = 0.002) and volume (r = 0.680, P = 0.001). Significant dose reductions were observed for the lungs (mean V10: 19.58 cc, V20: 17.13 cc, Dmean: 86.24 cGy) and heart (Dmean: 170.23 cGy). No significant differences were observed for CN (0.62-0.67) and HI (0.19-0.20) of the CTV. Conclusion: The application of a radiation bra was associated with better geometric and dosimetric planning parameters, with a smaller CTV and lower doses to the OARs (lungs and heart) in the radiotherapy field. In addition, we expect that bra use during radiotherapy would provide emotional benefits.

scholarly journals Dose Prediction Models Based on Geometric and Plan Optimization Parameter for Adjuvant Radiotherapy Planning Design in Cervical Cancer Radiotherapy

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Hui Tang ◽  
Yazheng Chen ◽  
Jialiang Jiang ◽  
Kemin Li ◽  
Jing Zeng ◽  
...  
Keyword(s):  
Cervical Cancer ◽  
Prediction Models ◽  
Organs At Risk ◽  
Target Volume ◽  
Radiotherapy Planning ◽  
Factors Affecting ◽  
Dose Prediction ◽  
Plan Optimization ◽  
Dose Volume ◽  
Optimization Parameters

The prediction of an additional space for the dose sparing of organs at risk (OAR) in radiotherapy is still difficult. In this pursuit, the present study was envisaged to find out the factors affecting the bladder and rectum dosimetry of cervical cancer. Additionally, the relationship between the dose-volume histogram (DVH) parameters and the geometry and plan dose-volume optimization parameters of the bladder/rectum was established to develop the dose prediction models and guide the planning design for lower OARs dose coverage directly. Thirty volume modulated radiation therapy (VMAT) plans from cervical cancer patients were randomly chosen to build the dose prediction models. The target dose coverage was evaluated. Dose prediction models were established by univariate and multiple linear regression among the dosimetric parameters of the bladder/rectum, the geometry parameters (planning target volume (PTV), volume of bladder/rectum, overlap volume of bladder/rectum (OV), and overlapped volume as a percentage of bladder/rectum volume (OP)), and corresponding plan dose-volume optimization parameters of the nonoverlapping structures (the structure of bladder/rectum outside the PTV (NOS)). Finally, the accuracy of the prediction models was evaluated by tracking d = (predicted dose-actual dose)/actual in additional ten VMAT plans. V30, V35, and V40 of the bladder and rectum were found to be multiple linearly correlated with the relevant OP and corresponding dose-volume optimization parameters of NOS (regression R2 > 0.99, P < 0.001 ). The variations of these models were less than 0.5% for bladder and rectum. Percentage of bladder and rectum within the PTV and the dose-volume optimization parameters of NOS could be used to predict the dose quantitatively. The parameters of NOS as a limited condition could be used in the plan optimization instead of limiting the dose and volume of the entire OAR traditionally, which made the plan optimization more unified and convenient and strengthened the plan quality and consistency.

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