scholarly journals Dosimetric comparison of radiotherapy treatment plans done by IMRT and VMAT technique in head and neck cancer patients

2021 ◽  
Vol 9 (3) ◽  
pp. 167-171
Author(s):  
Dr. Aparajeeta Aparajeeta ◽  
◽  
Dr. Ankita Mehta ◽  
Mr. N.S. Silambarasan ◽  
Dr. Piyush Kumar ◽  
...  
Keyword(s):  
Head And Neck Cancer ◽  
Head And Neck ◽  
Cancer Patients ◽  
Neck Cancer ◽  
Treatment Time ◽  
Statistical Significance ◽  
Target Volume ◽  
Treatment Delivery ◽  
Patient Load ◽  
Treatment Plans

Background: The increasing patient load in radiotherapy centres demands selection of thetechnique that provides plans with optimal dosimetry in terms of target volume coverage, organs atrisk (OAR) sparing and a lesser treatment time. This study was designed to compare the two widelypractised conformal techniques, IMRT and VMAT in head and neck cancer patients in terms ofplanning target volume (PTV) coverage, OAR sparing and treatment delivery parameters. Materialsand methods: For ten postoperative head and neck cancer patients who had been treated by IMRTtechnique virtual VMAT plans were generated for study purposes. The dose prescribed to PTV was 60Gy in 30 fractions. The dose-volume parameters of PTV and OARs and the treatment deliveryparameters were compared amongst both the techniques. Statistical significance was calculatedusing paired ‘t’ test. Results: Both the plans were comparable in terms of dosimetry. The onlysignificant difference being better conformity in the IMRT plans. The dose to OARs was alsocomparable in both the techniques except for a significant reduction in the point dose to brainstemwith the IMRT technique. Given the treatment delivery parameters, there was a significant reductionin the treatment delivery time and monitor units with the VMAT technique compared to the IMRTtechnique. Conclusion: VMAT technique gave comparable plans to that of the IMRT technique interms of dosimetry but reduced the treatment time. It seems feasible in radiotherapy centres withincreased patient load.

scholarly journals Reducing Referral-to-Treatment Waiting Times in Cancer Patients Using a Multidisciplinary Database

2007 ◽  
Vol 89 (2) ◽  
pp. 113-117 ◽  
Author(s):  
SAR Nouraei ◽  
J Philpott ◽  
SM Nouraei ◽  
DCK Maude ◽  
GS Sandhu ◽  
...  
Keyword(s):  
Head And Neck Cancer ◽  
Head And Neck ◽  
Cancer Patients ◽  
Treatment Planning ◽  
Neck Cancer ◽  
Treatment Time ◽  
Waiting Times ◽  
Multidisciplinary Teams ◽  
Number Of Patients ◽  
Cancer Plan

INTRODUCTION Modern delivery of cancer care through patient-centred multidisciplinary teams (MDT) has improved survival. This approach, however, requires effective on-going co-ordination between multiple specialties and resources and can present formidable organisational challenges. The aim of this study was to improve the efficiency of the MDT process for head and neck cancer. PATIENTS AND METHODS A systems analysis of the MDT process was undertaken to identify bottlenecks delaying treatment planning. The MDT process was then audited. A revised process was developed and an Intranet-based data management solution was designed and implemented. The MDT process was re-evaluated to complete the audit cycle. RESULTS We designed and implemented a trust-wide menu-driven database with interfaces for registering and tracking patients, and automated worklists for pathology and radiology. We audited our MDT for 11 and 10 weeks before and following the introduction of the database, with 226 and 187 patients being discussed during each period. The database significantly improved cross-specialtity co-ordination, leading to a highly significant reduction in the number of patients whose treatment planning was delayed due to unavailability of adjunctive investigations (P < 0.001). This improved the overall efficiency of the MDT by 60%. CONCLUSIONS The NHS Cancer Plan aspires to reduce the referral-to-treatment time to 1 month. We have shown that a simple, trust-wide database reduces treatment planning delays in a sizeable proportion of head and neck cancer patients with minimal resource implications. This approach could easily be applied in other MDT meetings.

scholarly journals Deterioration of Intended Target Volume Radiation Dose Due to Anatomical Changes in Patients with Head-and-Neck Cancer

Cancers ◽  
2021 ◽  
Vol 13 (17) ◽  
pp. 4253
Author(s):  
Olga Hamming-Vrieze ◽  
Simon van Kranen ◽  
Iris Walraven ◽  
Arash Navran ◽  
Abrahim Al-Mamgani ◽  
...  
Keyword(s):  
Head And Neck Cancer ◽  
Radiation Dose ◽  
Head And Neck ◽  
Cancer Patients ◽  
Neck Cancer ◽  
Patient Selection ◽  
Patient Characteristics ◽  
Target Volume ◽  
Adaptive Radiotherapy ◽  
Clinical Patient

Delivered radiation dose can differ from intended dose. This study quantifies dose deterioration in targets, identifies predictive factors, and compares dosimetric to clinical patient selection for adaptive radiotherapy in head-and-neck cancer patients. One hundred and eighty-eight consecutive head-and-neck cancer patients treated up to 70 Gy were analyzed. Daily delivered dose was calculated, accumulated, and compared to the planned dose. Cutoff values (1 Gy/2 Gy) were used to assess plan deterioration in the highest/lowest dose percentile (D1/D99). Differences in clinical factors between patients with/without dosimetric deterioration were statistically tested. Dosimetric deterioration was evaluated in clinically selected patients for adaptive radiotherapy with CBCT. Respectively, 16% and 4% of patients had deterioration over 1 Gy in D99 and D1 in any of the targets, this was 5% (D99) and 2% (D1) over 2 Gy. Factors associated with deterioration of D99 were higher baseline weight/BMI, weight gain early in treatment, and smaller PTV margins. The sensitivity of visual patient selection with CBCT was 22% for detection of dosimetric changes over 1 Gy. Large dose deteriorations in targets occur in a minority of patients. Clinical prediction based on patient characteristics or CBCT is challenging and dosimetric selection tools seem warranted to identify patients in need for ART, especially in treatment with small PTV margins.

Dosimetric Comparison of Helical Tomotherapy and Linac-IMRT Treatment Plans for Head and Neck Cancer Patients

2010 ◽  
Vol 35 (4) ◽  
pp. 264-268 ◽  
Author(s):  
Xin Zhang ◽  
Jose Penagaricano ◽  
Eduardo G. Moros ◽  
Peter M. Corry ◽  
Yulong Yan ◽  
...  
Keyword(s):  
Head And Neck Cancer ◽  
Head And Neck ◽  
Cancer Patients ◽  
Neck Cancer ◽  
Helical Tomotherapy ◽  
Dosimetric Comparison ◽  
Treatment Plans

scholarly journals Recurrence Patterns After IMRT/VMAT in Head and Neck Cancer

2021 ◽  
Vol 11 ◽  
Author(s):  
Heleen Bollen ◽  
Julie van der Veen ◽  
Annouschka Laenen ◽  
Sandra Nuyts
Keyword(s):  
Head And Neck Cancer ◽  
Head And Neck ◽  
Neck Cancer ◽  
Survival Rates ◽  
Volumetric Modulated Arc Therapy ◽  
Target Volume ◽  
High Dose ◽  
Treatment Delivery ◽  
Target Volume Definition ◽  
Dose Volume

PurposeIntensity-modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT), two advanced modes of high-precision radiotherapy (RT), have become standard of care in the treatment of head and neck cancer. The development in RT techniques has markedly increased the complexity of target volume definition and accurate treatment delivery. The aim of this study was to indirectly investigate the quality of current TV delineation and RT delivery by analyzing the patterns of treatment failure for head and neck cancer patients in our high-volume RT center.MethodsBetween 2004 and 2014, 385 patients with pharyngeal, laryngeal, and oral cavity tumors were curatively treated with primary RT (IMRT/VMAT). We retrospectively investigated locoregional recurrences (LRR), distant metastases (DM), and overall survival (OS).ResultsMedian follow-up was 6.4 years (IQR 4.7–8.3 years) during which time 122 patients (31.7%) developed LRR (22.1%) and DM (17.7%). The estimated 2- and 5-year locoregional control was 78.2% (95% CI 73.3, 82.3) and 74.2% (95% CI 69.0, 78.8). One patient developed a local recurrence outside the high-dose volume and five patients developed a regional recurrence outside the high-dose volume. Four patients (1.0%) suffered a recurrence in the electively irradiated neck and two patients had a recurrence outside the electively irradiated neck. No marginal failures were observed. The estimated 2- and 5-year DM-free survival rates were 83.3% (95% CI 78.9, 86.9) and 80.0% (95% CI 75.2, 84.0). The estimated 2- and 5-year OS rates were 73.6% (95% CI 68.9, 77.8) and 52. 6% (95% CI 47.3, 57.6). Median OS was 5.5 years (95% CI 4.5, 6.7).ConclusionTarget volume definition and treatment delivery were performed accurately, as only few recurrences occurred outside the high-dose regions and no marginal failures were observed. Research on dose intensification and identification of high-risk subvolumes might decrease the risk of locoregional relapses. The results of this study may serve as reference data for comparison with future studies, such as dose escalation or proton therapy trials.

scholarly journals A beállítási biztonsági margó nagyságának meghatározása fej-nyak daganatok 2D-2D és 3D képvezérelt intenzitásmodulált sugárkezelése esetén

2018 ◽  
Vol 159 (29) ◽  
pp. 1193-1200
Author(s):  
Péter Kovács ◽  
Evelin Szita ◽  
Kitti Schvarcz ◽  
Szabolcs Kamu ◽  
Judit Kalincsák ◽  
...  
Keyword(s):  
Head And Neck Cancer ◽  
Image Registration ◽  
Head And Neck ◽  
Cancer Patients ◽  
Neck Cancer ◽  
Target Volume ◽  
Setup Error ◽  
Error Determination ◽  
Imaging Time ◽  
Significant Difference

Abstract: Introduction: Image-guided intensity-modulated radiation therapy is essential for oncology treatment of head-and-neck cancer patients. Aim: MV-kV and CBCT modalities were compared in case of IGRT treatment for head-and-neck cancer patients. Setup error, setup margin (SM), imaging and evaluation times and imaging doses were analyzed. Method: Eight patients’ elective treatment was evaluated, 66 orthogonal MV-kV images and 66 CBCT series were acquired. Setup error measurement was based on bony manual image registration in three translational directions. Normality test and F-test were performed followed by the comparison with independent-samples T-test (p<0,05). The necessary target volume setup margin was calculated based on Van Herk’s equation. Imaging time and setup error determination time were measured. Imaging doses were estimated based on the literature. Results: No statistically significant difference was found between setup errors determined by MV-kV and CBCT (VRT: 0.5 mm, SD = 1.9 vs. 0.4 mm, SD = 2.1, p = 0.371; LNG: 0.2 mm, SD = 2.2 vs. –0.1 mm, SD = 2.2, p = 0.188; LAT: 0.2 mm, SD = 2.2 vs. 0.3 mm, SD = 2.1, p = 0.41). SM values were: VRT: 2.7 mm vs. 2.5 mm; LNG: 2.1 mm vs. 1.3 mm; LAT: 2.2 mm vs. 2.3 mm. Mean imaging time was 0.65 min (MV-kV) vs. 2.29 min (CBCT). Mean setup error determination time was 2.41 min for both modalities. Estimated imaging doses were 6.88 mGy (MV-kV) vs. 17.2 mGy (CBCT) per fraction. Conclusion: The bony anatomy derived image registration based translational setup error determination results in similar values either by MV-kV or by CBCT. Using 3 mm setup margin in all the directions might be adequate. Imaging time is less by MV-kV, significant difference in imaging doses did not appear. Using CBCT is generally suggested. MV-kV might be an alternative in case of need for shortened imaging time. Orv Hetil. 2018; 159(29): 1193–1200.

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