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No clear criteria have yet been established to guide decision-making for patient selection and the optimal timing of adaptive radiotherapy (ART) based on image-guided radiotherapy (IGRT). We have developed a novel protocol—the Best for Adaptive Radiotherapy (B-ART) protocol—to guide patient selection for ART. The aim of the present study is to describe this protocol, to evaluate its validity in patients with head and neck (HN) cancer, and to identify the anatomical and clinical predictors of the need for replanning. We retrospectively evaluated 82 patients with HN cancer who underwent helical tomotherapy (HT) and subsequently required replanning due to soft tissue changes upon daily MVCT. Under the proposed criteria, patients with anatomical changes >3 mm on three to four consecutive scans are candidates for ART. We compared the volumes on the initial CT scan (iCT) and the replanning CT (rCT) scan for the clinical target volumes (CTV1, referring to primary tumor or tumor bed and CTV2, metastatic lymph nodes) and for the parotid glands (PG) and body contour (B-body). The patients were stratified by primary tumor localization, clinical stage, and treatment scheme. The main reasons for replanning were: (1) a planning target volume (PTV) outside the body contour (n = 70; 85.4%), (2) PG shrinkage (n = 69; 84.1%), (3) B-body deviations (n = 69; 84.1%), and (4) setup deviations (n = 40; 48.8%). The replanning decision was made, on average, during the fourth week of treatment (n = 47; 57.3%). The mean reductions in the size of the right and left PG volumes were 6.31 cc (20.9%) and 5.98 cc (20.5%), respectively (p < 0.001). The reduction in PG volume was ≥30% in 30 patients (36.6%). The volume reduction in all of the anatomical structures was statistically significant. Four variables—advanced stage disease (T3−T4), chemoradiation, increased weight loss, and oropharyngeal localization—were significantly associated with the need for ART. The B-ART protocol provides clear criteria to eliminate random errors, and to allow for an early response to relevant changes in target volumes.

The aim of the study was to determine the influence of a key treatment plan and beam parameters on overall dose distribution and on doses in organs laying in further distance from the target during prostate SBRT. Multiple representative treatment plans (n = 12) for TrueBeam and CyberKnife were prepared and evaluated. Nontarget doses were measured with anionization chamber, in a quasi-humanoid phantom at four sites corresponding to the intestines, right lung, thyroid, and head. The following parameters were modified: radiotherapy technique, presence or not of a flattening filter, degree of modulation, and use or not of jaw tracking function for TrueBeam and beam orientation set-up, optimization techniques, and number of MUs for CyberKnife. After usual optimization doses in intestines (near the target) were 0.73% and 0.76%, in head (farthest from target) 0.05% and 0.19% for TrueBeam and CyberKnife, respectively. For TrueBeam the highest peripheral (head, thyroid, lung) doses occurred for the VMAT with the flattening filter while the lowest for 3DCRT. For CyberKnife the highest doses were for gantry with caudal direction beams blocked (gantry close to OARs) while the lowest was the low modulated VOLO optimization technique. The easiest method to reduce peripheral doses was to combine FFF with jaw tracking and reducing monitor units at TrueBeam and to avoid gantry position close to OARs together with reduction of monitor units at CyberKnife, respectively. The presented strategies allowed to significantly reduce out-of-field and nontarget doses during prostate radiotherapy delivered with TrueBeam and CyberKnife. A different approach was required to reduce peripheral doses because of the difference in dose delivery techniques: non-coplanar using CyberKnife and coplanar using TrueBeam, respectively.

Purpose: One of the main challenges in facial region brachytherapy is fixation of vendor-delivered standard applicators. Reproducibility can be maintained; however, there are frequent problems with applicator fitting to the skin surface in pleated regions. Manually prepared individual moulds require technological facilities and highly-trained staff. This article presents 3D-printed applicator preparation for a particular patient skin brachytherapy, using low-cost equipment and free software. We described applicator preparation in a step-by-step workflow., Material and Methods: This study demonstrated preparation of a skin brachytherapy applicator for a challenging recurrent tumor located in the nose bridge. During first visit of patient, fiducial markers were placed to enclose treated region. Patient was computed tomography (CT)-scanned, and reconstruction of target volume and surrounding organs at risk (OARs) were performed using treatment planning system (TPS). In TPS on patient's surface, a 1-cm thick bolus was added as a body of applicator. Inside the bolus, source paths were designed, and pre-plan was prepared. Using Beben - DICOM to standard triangle language (STL) software, the body of applicator and source-paths from pre-planning was transformed into an STL file, which was used as a solid definition in 3D printing., Results: The printed applicator fitted very well, and its' placement was quickly consistent regarding placing and securing. CTV was slightly broader in treatment plan (0.34 cm 3 vs. 0.31 cm 3 ), and doses given to CTV were lower, except for V 150 , which was higher for the realized plan (1.15% vs. 1.83%). All reported doses to OARs were lower in the realized plan., Conclusions: A low-cost 3D printer and widely available PLA filaments seem feasible to produce individual contact applicators for skin brachytherapy. Beben - DICOM to STL software and presented workflow appear to be convenient and simple tool., Competing Interests: The authors and related institutions do not guarantee 100% security of the proposed solutions. We call for a review of the presented conduct path and subject the given procedure to all available quality control measures. The authors and related institutions do not take any responsibility for clinical application of the presented solutions. There is no conflict of interests to declare.The authors report no conflict of interest., (Copyright © 2022 Termedia.)

Our understanding of low dose, out-of-field radiation and their radiobiological effects are limited, in part due to the rapid technological advances in external beam radiotherapy, especially for non-coplanar and dynamic techniques. Reliable comparisons of out-of-field doses produced by advanced radiotherapy techniques are difficult due to the limitations of commercially available phantoms. There is a clear need for a functional phantom to accurately measure the dosimetric and radiobiological characteristics of out-of-field doses, which would in turn allow clinicians and medical physicists to optimize treatment parameters. We designed, manufactured, and tested the performance of a quasi-humanoid (Q-H) adult phantom. To test the physics parameters, we used computed tomography (CT) scans of assembled Q-H phantom. Static open field and dynamic techniques were measured both in- and out-of-field with ionization chambers and radiochromic films for two configurations (full solid and with water-filled containers). In the areas simulating soft tissues, lung, and bones, median Hounsfield units and densities were, respectively: 129.8, -738.7, 920.8 HU and 1.110, 0.215, 1.669 g/cm 3 . Comparison of the measured to treatment planning systems (TPS) in-field dose values for the sample volumetric arc therapy (VMAT) (6 MV flattening filter-free (FFF)) plan, 96.4% of analyzed points passed the gamma evaluation criteria (L2%/2 mm, threshold (TH) 10%) and less than 1.50% for point dose verification. In the two phantom configurations: full poly(methyl) methacrylate (PMMA) and with water container, the off-axis median doses for open field, relative to the central axis of the beam (CAX) were similar, respectively: 0.900% versus 0.907% (15 cm distance to CAX); 0.096% versus 0.120% (35 cm); 0.018% versus 0.018% (52 cm); 0.009% versus 0.008% (74 cm). For VMAT 6 MV FFF, doses relative the CAX were, respectively: 0.667% (15 cm), 0.062% (35 cm), 0.019% (52 cm), 0.016% (74 cm). The Q-H phantom meets the International Commission on Radiation Units and Measurements (ICRU) and American Association of Physicists in Medicine (AAPM) recommended phantom criteria, providing medical physicists with a reliable, comprehensive system to perform dose calculation and measurements and to assess the impact on radiobiological response and on the risk of secondary tumor induction., (© 2022 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, LLC on behalf of The American Association of Physicists in Medicine.)

(1) Current breast-conserving therapy for breast cancer consists of a combination of many consecutive treatment modalities. The most crucial goal of postoperative treatment is to eradicate potentially relapse-forming residual cancerous cells within the tumor bed. To achieve this, the HDR brachytherapy boost standardly added to external beam radiotherapy was enhanced with an initial thermal boost. This study presents an original thermal boost technique developed in the clinic. (2) A detailed point-by-point description of thermal boost application is presented. Data on proper patient selection, microwave thermal boost planning, and interstitial hyperthermia treatment delivery are supported by relevant figures and schemes. (3) Out of 1134 breast cancer patients who were administered HDR brachytherapy boost in the tumor bed, 262 were also pre-heated interstitially without unexpected complications. The results are supported by two example cases of hyperthermia planning and delivery. (4) Additional breast cancer interstitial thermal boost preceding HDR brachytherapy boost as a part of combined treatment in a unique postoperative setting was feasible, well-tolerated, completed in a reasonable amount of time, and reproducible. A commercially available interstitial hyperthermia system fit and worked well with standard interstitial brachytherapy equipment.

The current situation and management of Ukrainian patients at 2 European cancer care centers in Poland and Italy is described. Both centers admit refugees from the war in Ukraine., (© 2022 The Authors.)

Background: Hypofractionated stereotactic body radiation therapy (SBRT) for prostate cancer (PCa) can be delivered with the robot-assisted CyberKnife (CK) system or on a linear accelerator using dynamic intensity-modulated radiotherapy (IMRT) or volumetric arc radiotherapy (VMAT). This retrospective study was performed to determine whether CK offers better dose distribution than IMRT and/or VMAT., Materials and Methods: Treatment plans for three techniques were prepared using the same treatment parameters (36.35 Gy, 7.25 Gy/fr). We evaluated target coverage, conformity index (CI), homogeneity index (HI), gamma index (GI), and organs at risk (OAR) constraints., Results: The mean planning target volume (PTV) dose for CK (39.58 Gy) was significantly greater than VMAT or IMRT (both 36.25 Gy). However, CK resulted in a wider dose range (31.48 to 45.89 Gy) vs . VMAT and IMRT (34.6-38.76 Gy). The mean dose to the rectum (V36Gy, mm 3 ) was significantly lower (p < 0.001) in the CK plans (219.78 vs . 519.59 and 422.62, respectively). The mean bladder dose (V37Gy, mm 3 ) was significantly greater for CK (3256 vs . 1090.75 for VMAT and 4.5 for IMRT (p < 0.001). CK yielded significantly better CI (1.07 vs . 1.17 and 1.25 for VMAT and IMRT, respectively; p < 0.01) and HI values (1.27 vs . 1.07 and 1.04; p < 0.01). GI values for the δd = 3mm, δ% = 3% criteria were 99.86 (VMAT), 99.07 (IMRT) and 99.99 (CK). For δd = 2mm, δ% = 2%, the corresponding values were 98.3, 93.35, and 97.12, respectively., Conclusions: For most variables, CK was superior to both VMAT and IMRT. However, dynamic IMRT techniques, especially VMAT, do not differ significantly from CK plans and are therefore acceptable alternatives to CyberKnife., (© 2022 Dorota Maria Borowicz, Agnieszka Skrobała, Marta Kruszyna-Mochalska, Julian Malicki, published by Sciendo.)

Recent comparison of an ultra-hypofractionated radiotherapy (UF-RT) boost to a conventionally fractionated (CF-RT) option showed similar toxicity and disease control outcomes. An analysis of the treatment plans for these patients is needed for evaluating calculated doses for different organs, treatment beam-on time, and requirements for human and financial resources. Eighty-six plans for UF-RT and 93 plans for CF-RT schemes were evaluated. The biologically equivalent dose, EQD2, summed for the first phase and the boost, was calculated for dose-volume parameters for organs at risk (OARs), as well as for the PTV1. ArcCHECK measurements for the boost plans were used for a comparison of planned and delivered doses. Monitor units and beam-on times were recorded by the Eclipse treatment planning system. Statistical analysis was performed with a significance level of 0.05. Dosimetric parameter values for OARs were well within tolerance for both groups. EQD2 for the PTV1 was on average 84 Gy for UF-RT patients and 76 Gy for CF-RT patients. Gamma passing rate for planned/delivered doses comparison was above 98% for both groups with 3 mm/3% distance to agreement/dose difference criteria. Total monitor units per fraction were 647 ± 94 and 2034 ± 570 for CF-RT and UF-RT, respectively. The total delivery time for boost radiation for the patients in the UF-RT arm was, on average, four times less than the total time for a conventional regimen with statistically equal clinical outcomes for the two arms in this study.

Background: The availability of linear accelerators (linac) for research purposes is often limited and therefore alternative radiation sources are needed to conduct radiobiological research. The National Centre for Radiation Research in Poland recently developed an intraoperative mobile linac that enables electron irradiation at energies ranging from 4 to 12 MeV and dose rates of 5 or 10 Gy/min. The present study was conducted to evaluate the electron beam parameters of this intraoperative linac and to verify the set-up to evaluate out-of-field doses in a water phantom, which were determined through dosimetric and biological response measurements., Materials and Methods: The distribution of radiation doses along and across the radiation beam were measured in a water phantom using a semiconductor detector and absolute doses using an ionisation chamber. Two luminal breast cancer cell lines (T-47D and HER2 positive SK-BR-3) were placed in the phantom to study radiation response at doses ranging from 2 to 10 Gy. Cell response was measured by clonogenic assays., Results and Conclusion: The electron beam properties, including depth doses and profiles, were within expected range for the stated energies. These results confirm the viability of this device and set-up as a source of megavoltage electrons to evaluate the radiobiological response of tumour cells., Competing Interests: Conflicts of interest None declared., (© 2021 Greater Poland Cancer Centre.)

Few studies have directly compared passive scattering (PS) to intensity-modulated proton therapy (IMPT) in the delivery of ultra-hypofractionated proton beams to the localized prostate cancer (PCa). In this preliminary study involving five patients previously treated with CyberKnife, treatment plans were created for PS and IMPT (36.25 CGE in five fractions with two opposing fields) to compare the dosimetric parameters to the planning target volume (PTV) and organs-at-risk (OAR: rectum, bladder, femoral heads). Both plans met the acceptance criteria. Significant differences were observed in the minimum and maximum doses to the PTV. The mean dose to the PTV was lower for PS (35.62 ± 0.26 vs. 37.18 ± 0.14; p = 0.002). Target coverage (D98%) was better for IMPT (96.79% vs. 99.10%; p = 0.004). IMPT resulted in significantly lower mean doses to the rectum (16.75 CGE vs. 6.88 CGE; p = 0.004) and bladder (17.69 CGE vs. 5.98 CGE p = 0.002). High dose to the rectum (V36.25 CGE) were lower with PS, but not significantly opposite to high dose to the bladder. No significant differences were observed in mean conformity index values, with a non-significant trend towards higher mean homogeneity index values for PS. Non-significant differences in the gamma index for both fields were observed. These findings suggest that both PS and IMPT ultra-hypofractionated proton therapy for PCa are highly precise, offering good target coverage and sparing of normal tissues and OARs.

Purpose: Brachytherapy is a great alternative for restrictive surgical procedures in facial cancers. Moreover, dose distribution is more beneficial compared with teleradiotherapy during treatment of lesions located on anatomical curves. However, repetitiveness of application is the main issue associated with using commercial applicators. The risk of its displacement is very unfavorable due to large dose gradients in brachytherapy. The aim of this study was to develop a process of preparation of applicators using 3D printing technology., Material and Methods: In planning system, circular volumes near the nose, eye, and ear were determined on transverse layers of an anthropomorphic phantom. Next, boluses with a thickness of 5 mm and 10 mm were designed for each of the layers. Channels in the 10 mm bolus were designed in such a way to place the catheters into the layers. Prepared applicators were printed using polylactic acid (PLA) filament. Plans to irradiate the films for their calibration and plans for treatment prepared in the treatment planning system were conducted. A special phantom was created to calibrate the radiochromic films. Dose distribution around the designed applicators was measured in an anthropomorphic phantom using films within the layers of phantom. Comparison of doses was performed with two-dimensional gamma analysis using OmniPro I'mRT software., Results: The obtained results confirmed compliance of the planned and measured doses in 92%; the analysis of gamma parameter showed 1%/1 mm for acceptability level of 95%. Moreover, the initial dosimetric analysis for gamma criteria with 2%/2 mm showed compliance at 99%., Conclusions: The results of the present study confirm potential clinical usefulness of the applicators obtained with the use of 3D printing for brachytherapy., Competing Interests: The authors report no conflict of interest., (Copyright © 2021 Termedia.)

Investigation of differences in derived [ 18 F]FDG PET metabolic and volumetric parameters among three different software programs in lung cancer. A retrospective analysis was performed on a group of 98 lung cancer patients who underwent a baseline [ 18 F]FDG PET/CT study. To assess appropriate delineation methods, the NEMA phantom study was first performed using the following software: Philips EBW (Extended Brilliance Workstation), MIM Software and Rover. Based on this study, the best cut-off methods (dependent on tumour size) were selected, extracted and applied for lung cancer delineation. Several semiquantitative [ 18 F]FDG parameters (SUV max , SUV mean , TLG and MTV) were assessed and compared among the three software programs. The parameters were assessed based on body weight (BW), lean body mass (LBM) and Bq/mL. Statistically significant differences were found in SUV mean (LBM) between MIM Software and Rover (4.62 ± 2.15 vs 4.84 ± 1.20; p < 0.005), in SUV mean (Bq/mL) between Rover and Philips EBW (21,852.30 ± 21,821.23 vs 19,274.81 ± 13,340.28; p < 0.005) and Rover and MIM Software (21,852.30 ± 21,821.23 vs 19,399.40 ± 10,051.30; p < 0.005), and in MTV between MIM Software and Philips EBW (19.87 ± 25.83 vs 78.82 ± 228.00; p = 0.0489). This study showed statistically significant differences in the estimation of semiquantitative parameters using three independent image analysis tools. These findings are important for performing further diagnostic and treatment procedures in lung cancer patients.

To assess adherence to standard clinical practice for the diagnosis and treatment of patients undergoing prostate cancer (PCa) radiotherapy in four European countries using clinical audits as part of the international IROCA project. Multi-institutional, retrospective cohort study of 240 randomly-selected patients treated for PCa (n = 40/centre) in the year 2015 at six European hospitals. Clinical indicators applicable to general and PCa-specific radiotherapy processes were evaluated. All data were obtained directly from medical records. The audits were performed in the year 2017. Adherence to clinical protocols and practices was satisfactory, but with substantial inter-centre variability in numerous variables, as follows: staging MRI (range 27.5-87.5% of cases); presentation to multidisciplinary tumour board (2.5-100%); time elapsed between initial visit to the radiation oncology department and treatment initiation (42-102.5 days); number of treatment interruptions ≥ 1 day (7.5-97.5%). The most common deviation from standard clinical practice was inconsistent data registration, mainly failure to report data related to diagnosis, treatment, and/or adverse events. This clinical audit detected substantial inter-centre variability in adherence to standard clinical practice, most notably inconsistent record keeping. These findings confirm the value of performing clinical audits to detect deviations from standard clinical practices and procedures.

Background: The aim of the study was to compare the TNM classification with 2-[ 18 F]FDG PE T biological parameters of primary tumor in patients with NSCLC., Materials and Methods: Retrospective analysis was performed on a group of 79 newly diagnosed NSCLC patients. PET scans were acquired on Gemini TF PET/CT scanner 60-70 min after injection of 2-[ 18 F]FDG with the mean activity of 364 ± 75 MBq, with the area being examined from the vertex to mid-thigh. The reconstructed PET images were evaluated using MIM 7.0 Software for SUV max , MTV and TLG values., Results: The analysis of the cancer stage according to TNM 8 th edition showed stage IA2 in 8 patients, stage IA3 - 6 patients, stage IB - 4 patients, IIA - 3 patients, 15 patients with stage IIB, stage IIIA - 17 patients, IIIB - 5, IIIC - 5, IVA in 7 patients and stage IVB in 9 patients. The lowest TLG values of primary tumor were observed in stage IA2 (11.31 ± 15.27) and the highest in stage IIIC (1003.20 ± 953.59). The lowest value of primary tumor in SUV max and MTV were found in stage IA2 (6.8 ± 3.8 and 1.37 ± 0.42, respectively), while the highest SUV max of primary tumor was found in stage IIA (13.4 ± 11.4) and MTV in stage IIIC (108.15 ± 127.24)., Conclusion: TNM stages are characterized by different primary tumor 2-[ 18 F]FDG PET parameters, which might complement patient outcome., Competing Interests: Conflict of interest None declared., (© 2021 Greater Poland Cancer Centre.)

The toxicity of radiotherapy is a key issue when analyzing the eligibility criteria for patients with breast cancer. In order to obtain better results, proton therapy is proposed because of the more favorable distribution of the dose in the patient's body compared with photon radiotherapy. Scientific groups have conducted extensive research into the improved efficacy and lower toxicity of proton therapy for breast cancer. Unfortunately, there is no complete insight into the potential reasons and prospects for avoiding undesirable results. Cardiotoxicity is considered challenging; however, researchers have not presented any realistic prospects for preventing them. We compared the clinical evidence collected over the last 20 years, providing the rationale for the consideration of proton therapy as an effective solution to reduce cardiotoxicity. We analyzed the parameters of the dose distribution (mean dose, Dmax, V5, and V20) in organs at risk, such as the heart, blood vessels, and lungs, using the following two irradiation techniques: whole breast irradiation and accelerated partial breast irradiation. Moreover, we presented the possible causes of side effects, taking into account biological and technical issues. Finally, we collected potential improvements in higher quality predictions of toxic cardiac effects, like biomarkers, and model-based approaches to give the full background of this complex issue.

Purpose: 3D printing has become a popular and widely available technique of rapid prototyping. The impact of used materials on the dose distribution has been studied for high energy sources. However, brachytherapy sources emit lower energy photons, and materials used in 3D printing may differ. This study was conducted to analyze the influence of common materials (polylactic acid - PLA and acrylonitrile butadiene styrene - ABS) used in stereolithography., Material and Methods: A 3D-printed phantom was designed, printed, and used to calibrate Gafchromic films. In the next step, a range of 1 mm thick plates of PLA and ABS (from zero to thirty) were inserted between source and detector to measure the impact of studied materials on delivered dose. Measurements were performed using a calibrated radiochromic film and Farmer ionization chamber in water., Results: No statistically significant correlation ( p = 0.4854) between the thickness of inserted PLA and the dose delivered to the film was obtained. With ionization chamber, Spearman's rank order test showed a significant correlation ( p = 0.00004); however, the correlation was found weak. In case of ABS measurement, a statistically significant ( p = 0.0159), yet weak negative correlation was found between the thickness of used material and the dose delivered to the film. On the other hand, a weak statistically significant ( p = 0.0212) but positive correlation was found when the dose was measured with Farmer ionization chamber. We find these correlations false, as all measured doses were within the measurement uncertainty range (film ±8.0%, Farmer ±8.8%) from 100% of the prescribed dose., Conclusions: According to obtained results, with the accuracy of measurement under clinical conditions, the impact of highly filled PLA and ABS printed objects on the dose distribution from an 192 Ir source in water can be omitted., Competing Interests: The authors report no conflict of interest., (Copyright © 2021 Termedia.)

Background: Patients with left breast cancer who undergo radiotherapy have a non-negligible risk of developing radiation-induced cardiovascular disease (CVD). Cardioprotection can be achieved through better treatment planning protocols and through respiratory gating techniques, including deep inspiration breath hold (DIBH). Several dosimetric studies have shown that DIBH reduces the cardiac dose, but clinical data confirming this effect is limited. The aim of the study was to compare the mean heart dose (MHD) in patients with left breast cancer who underwent radiotherapy at our institution as we transitioned from non-gated free-breathing (FB) radiotherapy to gated radiotherapy (FB-GRT), and finally to DIBH., Patients and Methods: Retrospective study involving 2022 breast cancer patients who underwent radiotherapy at West Pomeranian Oncology Center in Szczecin from January 1, 2014 through December 31, 2017. We compared the MHD in these patients according to year of treatment and technique., Results: Overall, the MHD for patients with left breast cancer in our cohort was 3.37 Gy. MHD values in the patients treated with DIBH were significantly lower than in patients treated with non-gated FB (2.1 vs . 3.48 Gy, p < 0.0001) and gated FB (3.28 Gy, p < 0.0001). The lowest MHD values over the four-year period were observed in 2017, when nearly 85% of left breast cancer patients were treated with DIBH. The proportion of patients exposed to high (> 4 Gy) MHD values decreased every year, from 40% in 2014 to 7.9% in 2017, while the percentage of patients receiving DIBH increased., Conclusions: Compared to free-breathing techniques (both gated and non-gated), DIBH reduces the mean radiation dose to the heart in patients with left breast cancer. These findings support the use of DIBH in patients with left breast cancer treated with radiotherapy., (© 2021 Michał Falco, Bartłomiej Masojć, Agnieszka Macała, Magdalena Łukowiak, Piotr Woźniak, Julian Malicki, published by Sciendo.)

Aim of the Study: To evaluate the agreement between planned and delivered doses and its potential correlation with the plans' complexity subjected to dosimetric verification., Material and Methods: Four isocentre volumetric modulated arc therapy for total marrow irradiation plans optimized simultaneously with (P1) and without (P2) MU reduction were evaluated dosimetrically by γ method performed in a global mode for 4 combinations of γ-index criteria (2%/2 mm, 2%/3 mm, 3%/2 mm, and 3%/3 mm). The evaluation was conducted for 4 regions (head and neck, chest, abdomen and upper pelvis, and lower pelvis and thighs) that were determined geometrically by the isocentres. The Wilcoxon test was used to detect significant differences between γ passing rate (GPR) analysis results for the P1 and P2 plans. The Pearson correlation was used to check the relationship between GPR and the plans' complexity., Results: Except for the head and neck region, the P2 plans had better GPRs than the P1 plans. Only for hard combinations of γ-index criteria (i.e. 2%/3 mm, 2%/2 mm) were the GPRs differences between P1 and P2 clinically meaningful, and they were detected in the chest, abdomen and upper pelvis, and lower pelvis and thighs regions. The highest correlations between GPR and the indices describing the plans' complexity were found for the chest region. No correlation was found for the head and neck region., Conclusions: The P2 plans showed better agreement between planned and delivered doses compared to the P1 plans. The GPR and the plans' complexity depend on the anatomy region and are most important for the chest region., (Copyright © 2021 Termedia.)

Purpose: To perform a clinical audit to assess adherence to standard clinical practice for the diagnosis, treatment, and follow-up of patients undergoing radiotherapy for rectal cancer treatment in four European countries., Materials and Methods: Multi-institutional, retrospective cohort study of 221 patients treated for rectal cancer in 2015 at six European cancer centres. Clinical indicators applicable to general radiotherapy processes were evaluated. All data were obtained from electronic medical records., Results: The audits were performed in the year 2017. We found substantial inter-centre variability in adherence to standard clinical practices: 1) presentation of cases at departmental clinical sessions (range, 0-100%) or multidisciplinary tumour board (50-95%); 2) pretreatment MRI (61.5-100%) and thoracoabdominal CT (15.0-100%). Large inter-centre differences were observed in the mean interval between biopsy and first visit to the radiotherapy department (range, 21.6-58.6 days) and between the first visit and start of treatment (15.1-38.8 days). Treatment interruptions ≥ 1 day occurred in 43.9% (2.5-90%) of cases overall. Treatment compensation was performed in 2.1% of cases. Treatment was completed in the prescribed time in 55.7% of cases., Conclusions: This multi-institutional clinical audit revealed that most centres adhered to standard clinical practices for most of the radiotherapy processes-related variables assessed. However, the audit revealed marked inter-centre variability for certain quality indicators, particularly inconsistent record keeping. Multiple targets for improvement and/or harmonisation were identified, confirming the value of routine clinical audits to detect potential deviations from standard clinical practice.

Greater Poland is a region with a high risk of cancer. In terms of age-standardised incidence rate, it is ranked 2nd for men and 3rd for women out of Poland's 16 provinces. Incidence structure in the region of Greater Poland is similar to that in other West European countries. The most common cancers in men are lung, prostate and colorectal, in women: breast, colorectal and lung. In 2016, nearly every third cancer-related death in the region was caused by lung cancer. In women, it was cause no. one. The incidence of chronic diseases, including cancer, is expected to further grow in view of the global ageing of the population. This means that malignancies will remain to be a major challenge for public health care.in the Greater Poland region., (© 2020 Greater Poland Cancer Centre. Published by Elsevier B.V. All rights reserved.)

Purpose: Evaluation of different planning methods of treatment plan preparation for volumetric modulated arc therapy during total marrow irradiation (VMAT-TMI)., Method: Three different planning methods were evaluated to establish the most appropriate VMAT-TMI technique, based on organ at risk (OAR) dose reduction, conformity and plan simplicity. The methods were: (M 1 ) the sub-plan method, (M 2 ) use of eight arcs optimised simultaneously and (M 3 ) M 2 with monitor unit reduction. Friedman ANOVA comparison, with Nemenyi's procedures, was used in the statistical analysis of the results., Results: The dosimetric results obtained for the planning target volume and for most OARs do not differ statistically between methods. The M 3 method was characterized by the lowest numbers of monitor units (3259 MU vs. 4450 MU for M 1 and 4216 MU for M 2 ) and, in general, the lowest complexity. The variability of the monitor units from control points was almost half for M 3 than M 1 and M 2 (i.e. 0.33 MU vs. 0.61 MU for M 1 and 0.58 for M 2 ). Analysing the relationship between the dose distributions obtained for the plans and their complexity, the best result was observed for the M 3 method., Conclusion: The use of eight simultaneously optimised arcs with MU reduction allows to obtain VMAT-TMI plans that are characterized by the lowest complexity, with dose distributions comparable to the plans generated by other methods., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.)

Purpose: To analyse the impact of different optimization strategies on the compatibility between planned and delivered doses during radiotherapy of cervical cancer., Material/methods: Four treatment plans differing in optimisation strategies were prepared for ten cervical cancer cases. These were: volumetric modulated arc therapy with (&#95;OPT) and without optimization of the doses in the bone marrow and for two sets of margins applied to the clinical target volume that arose from image guidance based on the bones (IG(B)) and soft tissues (IG(ST)). The plans were subjected to dosimetric verification by using the ArcCHECK system and 3DVH software. The planned dose distributions were compared with the corresponding measured dose distributions in the light of complexity of the plans and its deliverability., Results: The clinically significant impact of the plans complexity on their deliverability is visible only for the gamma passing rates analysis performed in a local mode and directly in the organs. While more general analyses show statistically significant differences, the clinical relevance of them has not been confirmed. The analysis showed that IG(ST)&#95;OPT and IG(B)&#95;OPT significantly differ from IG(ST) and IG(B). The clinical acceptance of IG(ST)&#95;OPT obtained for hard combinations of gamma acceptance criteria (2%/2 mm) confirm its satisfactory deliverability. In turn, for IG(B)&#95;OPT in the case of the rectum, the combination of 2%/2 mm did not meet the criteria of acceptance., Conclusion: Despite the complexity of the IG(ST)&#95;OPT, the results of analysis confirm the acceptance of its deliverability when 2%/2 mm gamma acceptance criteria are used during the analysis., (© 2020 Greater Poland Cancer Centre. Published by Elsevier B.V. All rights reserved.)

Objective: Several genetic analyses have identified tumor diversity not only among tumors from different patients (intertumor heterogeneity) but also within individual tumors (intratumor heterogeneity). The aim of this study was to analyze the intratumor heterogeneity and other biological parameters based on in vivo distribution in triple-tracer positron emission tomography with computed tomography (PET/CT) study in patients with newly diagnosed head and neck (H&N) cancer., Methods: Thirty-six patients with newly diagnosed H&N cancer were included in the study. Institutional Bioethical Committee approved the study protocol and informed consent was received from every participant. All patients underwent series of 3 PET/CT scans with [ 18 F]Fluorodeoxyglucose ( 18 F-FDG-PET), [ 18 F]Fluorothymidine ( 18 F-FLT-PET), and [ 18 F]Fluoromisonidazole ( 18 F-FMISO-PET) before treatment. Scans were performed on separate days, within a timeframe of 2 weeks. Several PET/CT parameters grading tumor biology including maximum standardized uptake value (SUV max ), total lesion glycolysis (TLG), its equivalent (total hypoxic lesion [TLH] and total proliferative lesion [TLP]), and heterogeneity (area under the curve-cumulative SUV histogram) for the primary tumor were compared., Results: All patients showed increased uptake of 18 F-FDG in primary tumor, ranging from 2.29 to 14.89 SUV max . Respectively, SUV max values for 18 F-FLT ranged from 0.93 to 16.11 and for 18 F-FMISO 0.36-4.07. Based on 3-year follow-up, we divided patients in terms of survival forecasts (first with good prognosis and second with worse). Higher values of TLG/TLP/TLH and SUV max were observed in the second group in all 3 tracers (for 18 F-FDG: 167.40 vs 100.32, 11.15 vs 8.95; for 18 F-FLT: 116.61 vs 60.67, 7.09 vs 5.47; for 18 F-FMISO: 37.34 vs 22.30, 1.70 vs 1.61 respectively). Statistically significant differences were shown in SUV max in 18 F-FDG and 18 F-FLT ( P <0.034, P <0.034, respectively; in TLG, P =0.05; TLP, P =0.04; and TLH, P =0.05)., Conclusion: Our preliminary results suggest worse prognosis in patients with higher heterogeneity values of primary tumor in proliferation and hypoxia images and combination of metabolic and volumetric parameters in TLG and its equivalent and heterogeneity of primary tumor seems to be a prognostic factor.

Objective: The aim of the study was to assess the feasibility of multitracer positron emission tomography (PET) imaging before and during chemoradiation and to evaluate the predictive value of image-based factors for outcome in locally advanced head and neck cancers treated with chemoradiation., Methods: In the week prior to the treatment [ 18 F]-2-flu-2-deoxy-D-glucose (FDG), [ 18 F]-3'-flu-3'deoxythymidine (FLT) and [ 18 F]-flumisonidazole (FMISO) imaging was performed. FLT scans were repeated at 14 and 28 Gy and FMISO at 36 Gy. Overall survival, disease-free survival and local control were correlated with subvolume parameters, and with tumour-to-muscle ratio for FMISO. For every tracer, total metabolic tumour volume was calculated., Results: 33 patients were included. No correlation was found between pre-treatment maximum standardised uptake value for FDG, FLT, FMISO and outcomes. Tumour volume measured on initial CT scans and initial FLT volume correlated with disease-free survivall ( p = 0.007 and 0.04 respectively). FDG and FLT metabolic tumour volumes correlated significantly with local control ( p = 0.005 and 0.02 respectively). In multivariate Cox analysis only individual initial TMRmax correlated with overall survival., Conclusion: PET/CT imaging is a promising tool. However, various aspects of image analysis need further clinical validation in larger multicentre study employing uniform imaging protocol and standardisation, especially for hypoxia tracer., Advances in Knowledge: Monitoring of biological features of the tumour using multitracer PET modality seems to be a feasible option in daily clinical practice.Evaluation of hypoxic subvolumes is more patient dependent; thus, exploration of individual parameters of hypoxia is needed. tumour-to-muscle ratio seems to be the most promising so far.

Background: The calculation and measurement on the surface of the skin presents a significant dosimetric problem because of numerous factors which have an influence on the dose distribution in this region., Aim: The overall aim of this study was to check the agreement between doses measured with thermoluminescent detectors (TLD) during tomotherapy photon beam irradiation of the skin area of a solid water cylindrical phantom with doses calculated with Hi-Art treatment planning system (TPS)., Material and Method: The measurements of the dose were made with the use of a solid water cylindrical phantom - Cheese Phantom. Two bolus phantoms were used: 5 mm and 10 mm Six different planning treatments were generated. The doses were measured using TL detectors., Results: In the case of a tumor located near the surface of the skin, the mean dose for 0.5 cm bolus was - 1.94 Gy, and for 1 cm bolus - 2.03 Gy. For the tumor located inside the phantom and organ at risk on the same side that TL detectors, for a 0.5 cm bolus, mean dose was 0.658 Gy, and for a 1 cm bolus, 0.62 Gy., Conclusion: The analysis of results showed that the relative percentage difference between measured and planned dose in the field of irradiation was less than 10%, while the largest differences were on the board of the field of radiation and outside of the field of irradiation, where the dose was 0.08 Gy to 1 Gy.