共查询到20条相似文献，搜索用时 62 毫秒
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Azza Helal Mohamed Farouk Sherief H. Gamie Mahran Abdo Lila Mosa Amr Abdul Aziz 《Practical radiation oncology》2018,8(2):71-80
Purpose
When treating breast cancer with radiation therapy, the impact of treatment position on heart and lung dose-volume parameters (DVPs) is largely dependent on the maximal heart distance (MHD) and central lung distance (CLD). We evaluate how much heart and lung sparing can be achieved using the semilateral decubitus (SLD) position without and with breath hold compared with the standard supine position for left-sided breast cancer patients. A secondary aim was to investigate the impact of MHD and CLD on heart and lung DVPs.Methods and materials
Thirty-five left-sided breast cancer patients were simulated in supine, free breathing SLD, and SLD with breath hold positions. A dosimetry plan was developed for each of these and 3 plans were compared for target coverage and organs at risk sparing. A correlation between CLD, MHD, and planning target volume, and heart and ipsilateral lung DVPs was tested.Results
SLD breath hold position showed a significant reduction in percentage of heart receiving ≥5 Gy (V5Gy), V10Gy, V25Gy, V30Gy, mean dose and maximum dose (P < .001), ipsilateral lung V20Gy, and mean dose compared with supine (P < 001) and free breathing SLD (P = .003 and .006). There was also a significant reduction in the heart DVPs (P < .001) and ipsilateral lung DVPs (P < .001 and .007) with free breathing SLD compared with the supine position. SLD with or without breath hold were associated with significant reduction in MLD (P < .001) and CLD (P = .030 and .003) compared with the supine position.Conclusion
Treatment plans for patients in the SLD position with or without breath hold for left-sided breast cancer patients demonstrated a superior heart and lung sparing compared with the supine position due to significant reduction in MHD and CLD. MHD and CLD are important simulation factors that affect the heart and lung DVP. 相似文献3.
Purpose
To investigate the effects of using volumetric modulated arc therapy (VMAT) and/or voluntary moderate deep inspiration breath-hold (vmDIBH) in the radiation therapy (RT) of left-sided breast cancer including the regional lymph nodes.Materials and methods
For 13 patients, four treatment combinations were compared; 3D-conformal RT (i.e., forward IMRT) in free-breathing 3D-CRT(FB), 3D-CRT(vmDIBH), 2 partial arcs VMAT(FB), and VMAT(vmDIBH). Prescribed dose was 42.56 Gy in 16 fractions. For 10 additional patients, 3D-CRT and VMAT in vmDIBH only were also compared.Results
Dose conformity, PTV coverage, ipsilateral and total lung doses were significantly better for VMAT plans compared to 3D-CRT. Mean heart dose (Dmean,heart) reduction in 3D-CRT(vmDIBH) was between 0.9 and 8.6 Gy, depending on initial Dmean,heart (in 3D-CRT(FB) plans). VMAT(vmDIBH) reduced the Dmean,heart further when Dmean,heart was still >3.2 Gy in 3D-CRT(vmDIBH). Mean contralateral breast dose was higher for VMAT plans (2.7 Gy) compared to 3DCRT plans (0.7 Gy).Conclusions
VMAT and 3D-CRT(vmDIBH) significantly reduced heart dose for patients treated with locoregional RT of left-sided breast cancer. When Dmean,heart exceeded 3.2 Gy in 3D-CRT(vmDIBH) plans, VMAT(vmDIBH) resulted in a cumulative heart dose reduction. VMAT also provided better target coverage and reduced ipsilateral lung dose, at the expense of a small increase in the dose to the contralateral breast. 相似文献4.
Soumyajit Roy Iulian Badragan Sheikh Nisar Ahmed Michael Sia Jorawur Singh Gaurav Bahl 《Practical radiation oncology》2018,8(5):e355-e363
Purpose
The purpose of this article was to generate an algorithm to calculate radiobiological endpoints and composite indices and use them to compare volumetric modulated arc therapy (VMAT) and 3-dimensional conformal radiation therapy (3D-CRT) techniques in patients with locally advanced non-small cell lung cancer.Methods and materials
The study included 25 patients with locally advanced non-small cell lung cancer treated with 3D-CRT at our center between January 1, 2010, and December 31, 2014. The planner generated VMAT plans using clones of the original computed tomography scans and regions of interest volumes, which did not include the original 3D plans. Both 3D-CRT and VMAT plans were generated using the same dose-volume constraint worksheet. The dose-volume histogram parameters for planning target volume and relevant organs at risk (OAR) were reviewed. The calculation engine was written in the R programming language; the user interface was developed with the “shiny" R Web library. Dose-volume histogram data were imported into the calculation engine and tumor control probability (TCP), normal tissue complication probability (NTCP), composite cardiopulmonary toxicity index (CPTI), morbidity index: MI?=?∑j?=?1#ofrelevantOARs(wj?1?NTCPj), uncomplicated TCP ( and therapeutic gain (TG): ie, TG?=?TCP?1?(100???MI) were calculated.Results
TCP was better with 3D-CRT (12.62% vs 11.71%, P < .001), whereas VMAT demonstrated superior NTCP esophagus (4.45% vs 7.39%, P?=?.02). NTCP spinal cord (0.001% vs 0.009%, P?=?.001), and NTCP heart/perfusion defect (44.57% vs 56.42%, P?=?.016). There was no difference in NTCP lung (6.27% vs 7.62%, P?=?.221) and NTCP heart/pericarditis (0.001% vs 0.15%, P?=?.129) between 2 techniques. VMAT showed substantial improvement in morbidity index (11.06% vs. 14.31%, P?=?0.01), CPTI (47.59% vs 59.41%, P?=?.03), TG (P = .035), and trend toward superiority in UTCP (5.89 vs 4.75, P=.057).Conclusion
The study highlights the utility of the radiobiological algorithm and summary indices in comparative plan evaluation and demonstrates benefits of VMAT over 3D-CRT. 相似文献5.
Amy S. Yu Peter G. Maxim Billy W. Loo Michael F. Gensheimer 《Practical radiation oncology》2018,8(4):e199-e207
Purpose
Stereotactic ablative radiation therapy (SABR) to lung tumors close to the chest wall can cause rib fractures or chest wall pain. We evaluated and propose a clinically practical solution of using noncoplanar volumetric modulated arc radiation therapy (VMAT) to reduce chest wall dose from lung SABR.Methods and materials
Twenty lung SABR VMAT plans in which the chest wall volume receiving 30 Gy or higher (V30) exceeded 30 mL were replanned by noncoplanar VMAT with opposite 15° couch kicks. Dosimetric parameters including chest wall V30 and V40; lung V5, V10, V20, and mean dose; Paddick high-dose conformity index; intermediate-dose conformity index; and monitor units (MU) for each plan were used to evaluate the plan quality. The treatment time was also estimated by delivering the entire treatment. Two-sided paired t test was used to evaluate the difference of the dosimetric parameters between coplanar 1 arc (cVMAT1), coplanar 2 arcs (cVMAT2), and noncoplanar two arcs (nVMAT2) plans; differences with P < .05 were considered statistically significant.Results
V30 and V40 for chest wall were reduced on average by 20% ± 9% and 15% ± 11% (mean ± standard deviation) from cVMAT2 plans to nVMAT2 plans (P < .01 for both comparisons) and by 8% ± 7% and 16% ± 13% from cVMAT1 plans to cVMAT2 plans (P < .003 for both comparisons). The differences in lung mean dose were <0.2 Gy among cVMAT1, cVMAT2, and nVMAT2. There were no significant differences in lung V5, V10, and V20. On average, the number of MU increased 14% for nVMAT2 compared with cVMAT2. The Paddick high-dose conformity indexes were 0.88 ± 0.03, 0.89 ± 0.04, and 0.91 ± 0.03, and intermediate-dose conformity indexes were 3.88 ± 0.49, 3.80 ± 0.44 and 3.51 ± 0.38 for cVMAT1, cVMAT2, and nVMAT2, respectively.Conclusions
We found that noncoplanar VMAT plans are feasible, clinically practical to deliver, and significantly reduce V30 and V40 of chest wall without increasing lung dose. 相似文献6.
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Yibing Wang Andras Zolnay Luca Incrocci Hans Joosten Todd McNutt Ben Heijmen Steven Petit 《Radiotherapy and oncology》2013
Background and purpose
To predict the lowest achievable rectum D35 for quality assurance of IMRT plans of prostate cancer patients.Materials and methods
For each of 24 patients from a database of 47 previously treated patients, the anatomy was compared to the anatomies of the other 46 to predict the minimal achievable rectum D35. The 24 patients were then replanned to obtain maximally reduced rectum D35. Next, the newly derived plans were added to the database to replace the original clinical plans, and new predictions of the lowest achievable rectum D35 were made.Results
After replanning, the rectum D35 reduced by 9.3 Gy ± 6.1 (average ± 1 SD; p < 0.001) compared to the original plan. The first predictions of the rectum D35 were 4.8 Gy ± 4.2 (average ± 1 SD; p < 0.001) too high when evaluated with the new plans. After updating the database, the replanned and newly predicted rectum D35 agreed within 0.1 Gy ± 2.8 (average ± 1 SD; p = 0.89). The doses to the bladder, anus and femoral heads did not increase compared to the original plans.Conclusions
For individual prostate patients, the lowest achievable rectum D35 in IMRT planning can be accurately predicted from dose distributions of previously treated patients by quantitative comparison of patient anatomies. These predictions can be used to quantitatively assess the quality of IMRT plans. 相似文献8.
Julien Charret Julia Salleron Magali Quivrin Frédéric Mazoyer Paul Lesueur Etienne Martin Didier Peiffert Gilles Créhange 《Practical radiation oncology》2018,8(5):e322-e328
Introduction
Prostate requires a daily correction of its 3-dimensional position in relation with rectal distension. In this study, we sought to determine whether rectal distension with respect to the rectal behavior might have an impact on prostate translations and/or rotations during prostate image guided radiation therapy using a 6 degrees-of-freedom (DOF) couch.Methods and materials
We reviewed the data from 39 patients with localized prostate cancer treated with protracted external radiation therapy using a 6 DOF couch. Before each fraction, a kilovoltage cone beam computed tomography (kV-CBCT) scan was performed. The automatic fusion algorithm was set to fuse on soft tissue and allowed correction for translations in 3 dimensions and rotations in the longitudinal axis (“roll”) and lateral axis (“pitch”). After contouring the rectum on each kV-CBCT, we determined the cross-sectional area (CSA) and relative CSA (CSArel) by dividing with the CSA of planning CT. The standard deviation of CSArel per patient was used to classify the patients in 2 groups: patients with a stable rectum and patients with an unstable rectum. The CSArel was compared between these 2 groups with a linear mixed model with group as fixed effect and patient as random effect.Results
A total of 616 kV-CBCT were analyzed, and 2 subgroups of patients could be defined a posteriori: 19 patients had a stable rectum, mean CSArel (1.06 ± 0.08); the other 20 patients had an unstable rectum, mean CSArel (1.43 ± 0.08). The average pitch in the group with a stable rectum was 0.36° (±0.21) versus 0.40° (±0.20) (P = .898). The pitch was not correlated with the CSArel (P = -.065, r = 0.119). The average roll in the group with a stable rectum was 0.27° (±0.16) versus 0.05° (±0.16) (P = .137). The roll was not correlated with the CSA (P = .094, r = 0.068). The average CSArel was higher (P = .0013) and more variable (P = .035) in the unstable group.Conclusion
Rectal distension had no impact on the pitch or on the roll, which suggest that a 6 DOF couch has little interest in daily practice for prostate image guided radiation therapy. 相似文献9.
Stephen R. Grant Benjamin D. Smith Anna O. Likhacheva Shervin M. Shirvani David B. Rosen B. Ashleigh Guadagnolo Dean A. Shumway Emma B. Holliday Daniel Chamberlain Gary V. Walker 《Practical radiation oncology》2018,8(5):e329-e336
Background
In this study, we sought to examine the variation in intensity modulated radiation therapy (IMRT) use among radiation oncology providers.Methods and materials
The Medicare Physician and Other Supplier Public Use File was queried for radiation oncologists practicing during 2014. Healthcare Common Procedural Coding System code 77301 was designated as IMRT planning with metrics including number of total IMRT plans, rate of IMRT utilization, and number of IMRT plans per distinct beneficiary.Results
Of 2759 radiation oncologists, the median number of total IMRT plans was 26 (mean, 33.4; standard deviation, 26.2; range, 11-321) with a median IMRT utilization rate of 36% (mean, 43%; standard deviation, 25%; range, 4% to 100%) and a median number of IMRT plans per beneficiary of 1.02 (mean, 1.07; range, 1.00-3.73). On multivariable analysis, increased IMRT utilization was associated with male sex, academic practice, technical fee billing, freestanding practice, practice in a county with 21 or more radiation oncologists, and practice in the southern United States (P < .05). The top 1% of users (28 providers) billed a mean 181 IMRT plans with an IMRT utilization rate of 66% and 1.52 IMRT plans per beneficiary. Of these 28 providers, 24 had billed technical fees, 25 practiced in freestanding clinics, and 20 practiced in the South.Conclusions
Technical fee billing, freestanding practice, male sex, and location in the South were associated with increased IMRT use. A small group of outliers shared several common demographic and practice-based characteristics. 相似文献10.
Dirk Wolff Florian Stieler Friedlieb Lorenz Sabine Mai Martin Polednik Frederik Wenz 《Radiotherapy and oncology》2009,93(2):226-233
Introduction
Volumetric modulated arc therapy (VMAT), a complex treatment strategy for intensity-modulated radiation therapy, may increase treatment efficiency and has recently been established clinically. This analysis compares VMAT against established IMRT and 3D-conformal radiation therapy (3D-CRT) delivery techniques.Methods
Based on CT datasets of 9 patients treated for prostate cancer step-and-shoot IMRT, serial tomotherapy (MIMiC), 3D-CRT and VMAT were compared with regard to plan quality and treatment efficiency. Two VMAT approaches (one rotation (VMAT1x) and one rotation plus a second 200° rotation (VMAT2x)) were calculated for the plan comparison. Plan quality was assessed by calculating homogeneity and conformity index (HI and CI), dose to normal tissue (non-target) and D95% (dose encompassing 95% of the target volume). For plan efficiency evaluation, treatment time and number of monitor units (MU) were considered.Results
For MIMiC/IMRTMLC/VMAT2x/VMAT1x/3D-CRT, mean CI was 1.5/1.23/1.45/1.51/1.46 and HI was 1.19/1.1/1.09/1.11/1.04. For a prescribed dose of 76 Gy, mean doses to organs-at-risk (OAR) were 50.69 Gy/53.99 Gy/60.29 Gy/61.59 Gy/66.33 Gy for the anterior half of the rectum and 31.85 Gy/34.89 Gy/38.75 Gy/38.57 Gy/55.43 Gy for the posterior rectum. Volumes of non-target normal tissue receiving ?70% of prescribed dose (53 Gy) were 337 ml/284 ml/482 ml/505 ml/414 ml, for ? 50% (38 Gy) 869 ml/933 ml/1155 ml/1231 ml/1993 ml and for ? 30% (23 Gy) 2819 ml/3414 ml/3340 ml/3438 ml /3061 ml. D95% was 69.79 Gy/70.51 Gy/71,7 Gy/71.59 Gy/73.42 Gy. Mean treatment time was 12 min/6 min/3.7 min/1.8 min/2.5 min.Conclusion
All approaches yield treatment plans of improved quality when compared to 3D-conformal treatments, with serial tomotherapy providing best OAR sparing and VMAT being the most efficient treatment option in our comparison. Plans which were calculated with 3D-CRT provided good target coverage but resulted in higher dose to the rectum. 相似文献11.
Zachary D. Horne Michael J. Dohopolski David A. Clump Steven A. Burton Dwight E. Heron 《Practical radiation oncology》2018,8(3):e117-e123
Purpose
Local failure following concurrent chemoradiation and in-lobe failures following stereotactic body radiation therapy (SBRT) are common. We evaluated our institutional experience using SBRT as salvage in this setting.Methods and materials
Seventy-two patients were reirradiated with SBRT for residual, locally recurrent, or new primary non-small cell lung cancer within or adjacent to a high-dose external beam radiation therapy or SBRT field. Kaplan-Meier analysis with log-rank test were used to estimate endpoints and differentiate cohorts.Results
Median follow-up was 17.9 months. Patients had residual or recurrent disease (54.2%); 45.8% had new lung primaries. Median reirradiated T size was 2.5 cm (range, 0.8-7.8 cm). Median pre-retreatment maximum standardized uptake value (SUVmax) was 7.15 (range, 1.2-37.6). The most common SBRT reirradiation regimen was 48 Gy in 4 fractions (range, 17-60 Gy in 1-5 fractions). Median progression-free survival was 15.2 months, and median overall survival was 20.8 months. Two-year local failure was 21.6%. Patients with SUVmax at reirradiation <7.0 had a 2-year local control of 93.1% versus 61.1% above the median (P < .001). The 2-year rate of distant metastases was 10.4% versus 54.1% in patients treated for a new primary versus residual or recurrent disease (P < .001). Median progression-free survival was 31.9 months versus 8.4 months, respectively (P = .037). Median survival of patients treated for new primary was 25.2 months versus 16.2 months with residual or recurrent disease (P = .049), and median survival for patients with reirradiation SUVmax below the median was 42.0 months versus 9.8 months above the median (P < .001). Acute any-grade toxicity was seen in 29.2% of patients, acute grade 3 toxicity in 11.1%, and late grade 3 toxicity in 1.4% with no treatment-related deaths.Conclusions
SBRT appears to be a safe and effective means of salvaging recurrent, residual, or new primary NSCLC in or adjacent to a previous high-dose radiation field. 相似文献12.
Rosanna Yeung Stephen R. Bowen Tobias R. Chapman Grayden T. MacLennan Smith Apisarnthanarax 《Practical radiation oncology》2018,8(4):287-293
Purpose
Normal liver-sparing with proton beam therapy (PBT) allows for dose escalation in the treatment of liver malignancies, but it may result in high doses to the chest wall (CW). CW toxicity (CWT) data after PBT for liver malignancies are limited, with most published reports describing toxicity after a combination of hypofractionated proton and photon radiation therapy. We examined the incidence and associated factors for CWT after hypofractionated PBT for liver malignancies.Methods and materials
We retrospectively reviewed the charts of 37 consecutive patients with liver malignancies (30 hepatocellular carcinoma, 6 intrahepatic cholangiocarcinoma, and 1 metastasis) treated with hypofractionated PBT. CWT was scored using Common Terminology Criteria for Adverse Events, version 4. Receiver-operating characteristic curves were used to identify patient and dosimetric factors associated with CWT and to determine optimal dose-volume histogram parameters/cutoffs. Cox regression univariate analysis was used to associate factors to time-dependent onset of CWT.Results
Thirty-nine liver lesions were treated with a median dose of 60 GyE (range, 35-67.5) in 15 fractions (range, 13-20). Median follow-up was 11 months (range, 2-44). Grade ≥2 and 3 CW pain occurred in 7 (19%) and 4 (11%) patients, respectively. Median time to onset of pain was 6 months (range, 1-14). No patients had radiographic rib fracture. On univariate analysis, CW equivalent 2 Gy dose with an α/β = 3 Gy (EQD2α/β=3), V57 >20 cm3 (hazard ratio [HR], 2.7; P = .004), V63 >17 cm3 (HR, 2.7; P = .003), and V78 >8 cm3 (HR, 2.6; P = .003) had the strongest association with grade ≥2 CW pain, as did tumor dose of >75 Gy EQD2α/β=10 (HR, 8.7; P = .03). No other patient factors were associated with CWT.Conclusions
CWT after hypofractionated PBT for liver malignancies is clinically relevant. For a 15-fraction regimen, V47 >20 cm3, V50 >17 cm3, and V58 >8 cm3 were associated with higher rates of CWT. Further investigation of PBT techniques to reduce CW dose are warranted. 相似文献13.
Purpose
To investigate the differences in treatment plan quality of IMRT and VMAT with and without flattening filter using Pareto optimal fronts, for two treatment sites of different anatomic complexity.Materials and Methods
Pareto optimal fronts (POFs) were generated for six prostate and head-and-neck cancer patients by stepwise reduction of the constraint (during the optimization process) of the primary organ-at-risk (OAR). 9-static field IMRT and 360°-single-arc VMAT plans with flattening filter (FF) and without flattening filter (FFF) were compared. The volume receiving 5 Gy or more (V5Gy) was used to estimate the low dose exposure. Furthermore, the number of monitor units (MUs) and measurements of the delivery time (T) were used to assess the efficiency of the treatment plans.Results
A significant increase in MUs was found when using FFF-beams while the treatment plan quality was at least equivalent to the FF-beams. T was decreased by 18% for prostate for IMRT with FFF-beams and by 4% for head-and-neck cases, but increased by 22% and 16% for VMAT. A reduction of up to 5% of V5Gy was found for IMRT prostate cases with FFF-beams.Conclusions
The evaluation of the POFs showed an at least comparable treatment plan quality of FFF-beams compared to FF-beams for both treatment sites and modalities. For smaller targets the advantageous characteristics of FFF-beams could be better exploited. 相似文献14.
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Klaus Bratengeier Bülent Polat Mark Gainey Patricia Grewenig Jürgen Meyer Michael Flentje 《Radiotherapy and oncology》2009,93(2):266-272
Background
The ability of a geometry-based method to expeditiously adapt a “2-Step” step and shoot IMRT plan was explored. Both changes of the geometry of target and organ at risk have to be balanced. A retrospective prostate planning study was performed to investigate the relative benefits of beam segment adaptation to the changes in target and organ at risk coverage.Methods
Four patients with six planning cases with extraordinarily large deformations of rectum and prostate were chosen for the study. A 9-field IMRT plan (A) using 2-Step IMRT segments was planned on an initial CT study. The plan had to fulfil all the requirements of a conventional high-quality step and shoot IMRT plan. To adapt to changes of the anatomy in a further CT data set, three approaches were considered: the original plan with optimized isocentre position (B), a newly optimized plan (C) and the original plan, adapted using the 2-Step IMRT optimization rules (D). DVH parameters were utilized for quantification of plan quality: D99 for the CTV and the central planning target volume (PTV), D95 for an outer PTV, V95, V80 and V50 for rectum and bladder.Results
The adapted plan (D) achieved almost the same target coverage as the newly optimized plan (C). Target coverage for plan B was poor and for the organs at risk, the rectum V80 was slightly increased. The volume with more than 95% of the target dose (V95) was 1.5 ± 1.5 cm3 for the newly optimized plan (C), compared to 2.2 ± 1.3 cm3 for the original plan (A) and 7.2 ± 4.8 cm3 (B) on the first and the second CT, respectively. The adapted plan resulted in 4.3 ± 2.1 cm3 (D), an intermediate dose load to the rectum. All other parameters were comparable for the newly optimized and the adapted plan.Conclusions
The first results for adaptation of interfractional changes using the 2-Step IMRT algorithm are encouraging. The plans were superior to plans with optimized isocentre position and only marginally inferior to a newly optimized plan. 相似文献16.
Kevin Yan Ezequiel Ramirez Xian-Jin Xie Xuejun Gu Yin Xi Kevin Albuquerque 《Practical radiation oncology》2018,8(1):13-19
Purpose
The purpose of this study was to determine factors predictive for severe hematologic toxicity (HT) in cervical cancer patients with para-aortic lymph node metastasis treated with concurrent cisplatin chemoradiation to an extended field (EFCRT).Methods and materials
Thirty-eight patients with cervical cancer and para-aortic lymph node metastasis who underwent EFCRT were analyzed. Active bone marrow was defined as the region within irradiated total bone marrow (BMTOT) with a standard uptake value on 18F-fluorodeoxyglucose positron emission tomography/computed tomography greater than the mean standard uptake value for BMTOT. Serial weekly blood counts from the beginning to the end of radiation treatment were evaluated for HT using Common Terminology Criteria for Adverse Events, version 4.0.Results
Nineteen patients had grade 3 or higher hematologic toxicity (HT3+), not including lymphocyte toxicity. Obese patients (n = 12) were less likely to get HT3+ (P = .03) despite getting equivalent doses of chemotherapy. Volumes of BMTOT and active bone marrow receiving doses of 20, 30, and 45 Gy and body mass index significantly predicted HT3+. Patients who had HT3+ had prolonged treatment time (62 vs 53 days, P < .001).Conclusions
For patients receiving EFCRT, bone marrow irradiation parameters and patient body mass index were associated with HT3+. A simplified nomogram has been created to predict HT3+ in these patients, allowing the potential to explore bone marrow–sparing delivery techniques. 相似文献17.
Purpose
A comprehensive set of planning guidelines was developed to aid in achieving reproducible dosimetric results for external beam accelerated partial breast irradiation (APBI). The methodology for the development of class solutions for dosimetric planning of the APBI technique, including dose constraint recommendations, is presented for target coverage and conformity as well as normal tissues.Methods and materials
A conservative patient setup was simulated on a linear accelerator, and a comprehensive arrangement of gantry and couch angles was measured for clearance. This provided the foundation for available beam arrangements to develop reproducible and conformal 5-field intensity modulated radiation therapy partial breast plans. Forty patients were planned. Patient plans were assessed according to anatomy specific features, such as laterality and seroma location within the breast.Results
Clearance tables are presented to give permissible gantry and couch orientations according to measurements facilitated by patient simulation. Beam arrangement class solutions are presented for left- and right-sided APBI patients. Dosimetric recommendations are made based on the results of 40 patient plans. The median and range, describing target coverage and target conformity, are reported, as are normal tissue constraints for ipsilateral lung, ipsilateral breast, heart, liver, and contralateral breast. In all cases, the dose recommendations were at least as strict as multi-institutional APBI trials. In the case of ipsilateral lung and ipsilateral breast, the planning recommendations are more stringent.Conclusions
APBI using a 5-field intensity modulated radiation therapy technique was comprehensively developed and evaluated to provide recommendations yielding highly conformal and reproducible treatment plans. This provides a clear method to implement external beam APBI planning and delivery. 相似文献18.
Kentaro Ishii Toshiko Yamanaga Ryo Ogino Yukinari Hosokawa Shun Kishimoto Ryuta Nakahara Chiaki Shimada Ryu Kawamorita Takuhito Tada Yoshiki Hayashi Toshifumi Nakajima 《Practical radiation oncology》2018,8(2):e49-e55
Purpose
This study aimed to compare bowel and urinary health-related quality of life (HRQOL) between prostate-only (PO) volumetric modulated arc therapy (VMAT) and whole-pelvis (WP) VMAT in patients with localized prostate cancer.Methods and materials
A total of 234 patients treated with definitive VMAT to 78 Gy in 39 fractions were enrolled. Of these, 108 patients received PO-VMAT and 126 patients received initial WP-VMAT to 46.8 Gy in 26 fractions using a simultaneous integrated boost technique. HRQOL was prospectively assessed before radiation therapy (baseline), and 3, 6, 12, and 24 months after treatment using the Expanded Prostate Cancer Index Composite (EPIC).Results
Baseline HRQOL scores did not differ significantly between the 2 groups. No significant between-group differences in HRQOL change from baseline were observed for all bowel and urinary EPIC domains. The proportion of patients showing a clinically relevant decrease in bowel and urinary HRQOL scores from baseline was similar between the groups throughout the follow-up period. An analysis of individual HRQOL items showed that patients undergoing WP-VMAT were more likely to report moderate/big problems with bloody stools (P = .039) and overall bowel problems (P = .008) than those undergoing PO-VMAT at 12 months. There was no significant between-group difference in any individual items at 24 months, however.Conclusions
Bowel and urinary HRQOL is largely similar for patients receiving PO-VMAT and WP-VMAT during 24 months of follow-up, with the only differences seen in responses to specific bowel HRQOL items at 12 months. 相似文献19.
Wenji Guo Xuan Hui Salem Alfaifi Lori Anderson Scott Robertson Russell Hales Chen Hu Todd McNutt Stephen Broderick Jarushka Naidoo Richard Battafarano Stephen Yang K. Ranh Voong 《Practical radiation oncology》2018,8(4):e239-e248