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Background: This work aimed to determine the optimum VOLO TM Ultra algorithm parameters for tomotherapy treatments., Methods: 1056 treatment plans were generated with VOLO TM Ultra for 36 patients and six anatomical locations. The impact of varying four parameters was studied: the accelerated treatment (AT), leaf open/close time (LOT) cutoff, normal tissue objective (NTO) weight, and number of iterations. The beam-on time and dosimetric metrics were quantified for the target volumes and organs at risk (OARs). Delivery quality assurance measurements were obtained for 36 plans to assess the delivery accuracy., Results: The mean beam-on time for the helical tomotherapy and TomoDirect (TD) plans decreased by 26.6 ± 2.8% and 17.4 ± 4.3%, respectively, when the accelerated treatment parameter was increased from 0 to 10, at the expense of the planning target volume (PTV) coverage (2% lower D 98% ) and OAR dose (up to 15% increase). For TD plans, it seems preferable to systematically use an AT value of 10. Increasing the number of iterations beyond six seems unnecessary. In this study, an NTO weight of approximately 10 appears to be ideal and eliminates the need to use rings in the treatment plan. Finally, no correlation was found between the leaf open/close time cutoff and the delivery accuracy, while a leaf open/close cutoff of 60 ms seemed to degrade dosimetry quality., Conclusion: Optimal values for the AT, LOT cutoff, NTO weight, and number of optimization rounds were identified and should help improve the management of patients whose tomotherapy treatments are planned with VOLO TM Ultra.

Background: Adaptive radiotherapy (ART) has the potential to reduce the toxicities of radiotherapy and improve overall survival by considering variations in the patient's anatomy during the course of treatment. ART's first commercial solutions are now implemented in clinical radiotherapy departments. However, before they can be used safely with real patients, these solutions must be rigorously evaluated to precisely determine the limits of their use., Methods: In this paper, we evaluated an offline ART vendor system in 50 patients treated on tomotherapy- like systems for six months. Illustrated by numerous examples of head and neck, thoracic and abdominopelvic localizations, two limitations of image processing used in the ART workflow have been highlighted: deformable image registration (DIR) accuracy and the way the limited field of view (FOV) is compensated. This feedback from clinical experience makes it possible to identify topics of image processing research with strong clinical interest., Results: Current DIR method accuracy may be too weak for some clinical ART applications, and their improvement remains highly important, especially for multimodality registration. Improvements in contour propagation methods also remain crucial today. We showed that there is a need for the development of automatic DIR accuracy quantification methods to help streamline the ART process. Finally, the limited FOV of the onboard images may induce dose calculation errors, highlighting the need to develop new FOV extension methods., Conclusion: We have evaluated a vendor ART system, but some image processing pitfalls, such as DIR accuracy and the limited FOV of the onboard images, make its implementation into clinical practice difficult for the moment., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Purpose: To show the usefulness of topographic 2D megavoltage images (MV2D) for the localization of breast cancer patients treated with TomoDirect (TD), a radiotherapy treatment technique with fixed-angle beams performed on a TomoTherapy system., Methods: A method was developed to quickly localize breast cancer patients treated with TD by registering the MV2D images produced before a TD treatment with reference images reconstructed from a kilovoltage CT simulation scanner and by using the projection of the beam-eye-view TD treatment field. Dose and image quality measurements were performed to determine the optimal parameters for acquiring MV2D images. A TD treatment was simulated on a chest phantom equipped with a breast attachment. MVCT and MV2D images were performed for 7 different shifted positions of the phantom and registered by 10 different operators with the simulation kilovoltage CT images., Results: Compared to MVCT, MV2D imaging reduces the dose by a factor of up to 45 and the acquisition time by a factor of up to 49. Comparing the registration shift values obtained for the phantom images obtained with MVCT in the coarse mode to those obtained with MV2D, the mean difference is 1.0±1.1mm, -1.1mm±1.1, and -0.1±2.2mm, respectively, in the lateral, longitudinal, and vertical directions., Conclusions: With dual advantages (very fast imaging and a potentially reduced dose to the heart and contralateral organs), MV2D topographic images may be an attractive alternative to MVCT for the localization of breast cancer patients treated with TomoDirect., (Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.)

Background and Purpose: TomoDirect (TD) can only operate in free-breathing. The purpose of this study is to compare TD with breath-hold 3D conformal radiotherapy (3DCRT) and intensity modulated radiotherapy (IMRT) techniques for left breast treatments, and to determine if the lack of respiratory gating is a handicap for cardiac sparing., Materials and Methods: 15 patients treated for left breast had two computed tomography simulation, in free breathing (FB) and in deep-inspiration breath-hold (DIBH). Four treatments were planned: TD-FB, 3DCRT-FB, 3DCRT-DIBH and IMRT-DIBH. Dose to PTV, heart, lungs, right breast and patient were compared., Results: A slightly lower cardiac mean dose is found for 3DCRT-DIBH than for TD-FB group (1.99Gy Vs 2.89Gy, p=0.0462), while no statistical difference is found for heart V20. TD-FB plans show the best PTV dose homogeneity (0.053, p<0.001) and the lowest left lung mean dose (5.16Gy, p<0.001). No major differences are found for the other organs., Conclusions: TomoDirect and breath-hold 3DCRT are complementary techniques for left breast treatments: for a minority of patients, respiratory gating is mandatory to lower cardiac dose; for the remaining majority of patients, TomoDirect achieves better PTV homogeneity and reduced left lung dose, with cardiac dose equivalent to 3DCRT-DIBH., (Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.)

Purpose: Retrospective analysis of the results of 52 children irradiated for a medulloblastoma., Patients and Methods: Between 1974 and 2012, 52 children with an average age of 6 years and a half (11 months-17 years and a half) were treated with surgery then with radiotherapy at the Comprehensive Cancer Centre of Strasbourg (France). For 44 children, the treatment consisted of a chemotherapy., Results: After a mean follow-up of 106.6 months (7-446 months), 13 relapses and 24 deaths were observed. Overall survival at 5 years and 10 years were 62% and 57%, respectively. Disease-free survival at 5 years and 10 years were 80% and 63%, respectively. Univariate analysis found the following adverse prognostic factors: the existence of a postoperative residue, the positivity of the cerebrospinal fluid, the metastatic status and medulloblastoma of high-risk. Positivity of the cerebrospinal fluid remains a negative factor in multivariate analysis., Conclusion: These results confirm the survival rate obtained by a conventional approach (surgery then irradiation). Insufficiency of results and rarity of medulloblastoma require the establishment of international protocols., (Copyright © 2016. Published by Elsevier SAS.)

Purpose: Retrospective analysis of the results of 21 adults treated for medulloblastoma., Patients and Methods: Between 1978 and 2011, 21 adults with an average age of 31 years (18.3-50) were treated with surgery then with radiotherapy (n=20) at the Comprehensive Cancer Center of Strasbourg. For some (n=12), treatment consisted of chemotherapy., Results: After a mean follow-up of 122 months (19-423), six relapses and seven deaths were observed. Overall survival at 5 years and 10 years was 89.4 ± 7.1% for both. Disease-free survival at 5 years and 10 years was 79.6 ± 9.2% and 85.7 ± 7.6% and 60.6 ± 17.7%, respectively., Conclusion: The rarity of medulloblastoma, especially in adults and these results confirm the necessity of international protocols., (Copyright © 2015 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.)

Background and Purpose: To determine the optimum combination of treatment parameters between pitch, field width (FW) and modulation factor (MF) for extremity sarcomas in tomotherapy., Materials and Methods: Six patients previously treated for extremity sarcomas (3 arms and 3 legs) with tomotherapy were included in this study. 288 treatment plans were recalculated, corresponding to all combinations between 2 FW (2.5 and 5 cm), 4 MF (1.5, 2, 2.5 and 3) and 6 pitches (0.215, 0.287, 0.43 and 3 off-axis pitches). The treatment parameters (MF, FW or pitch) are modified between each plan, and the calculation is relaunched for 400 iterations, without modifying the optimisation constraints of the plan under which the patient has been treated., Results: We suggest eliminating the 0.43 pitch and never combining a 0.215 pitch with an MF ≤ 2. We also do not recommend using an MF = 1.5 unless treatment time is an absolute priority over plan quality. We did not see any advantage in using Chen off-axis pitches, except for targets far from the axis (>15 cm) treated with a high pitch. A combination of MF = 2/FW = 5 cm/pitch = 0.287 gives plans of acceptable quality, combined with reduced treatment times. These conclusions are true only for extremity sarcomas treated in 2 Gy/fraction., Conclusions: We have shown that the choice of pitch/MF/FW combination is crucial for the treatment of extremity sarcomas in tomotherapy: some produce good dosimetric quality with a reduced irradiation time, while others may increase the time without improving the quality., (Copyright © 2015 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.)

Background: The majority of children under 3 years require anesthesia for radiotherapy., Methods: This work reports the experience of Paul-Strauss Center over a 4-year period on 15 children and covering 386 general anesthesia., Results and Conclusion: The rate of anesthesia-related complications was low (0.5%) subject to the experience of the anesthesiologists and follow-up recommendations., (Copyright © 2013 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.)

Purpose: We compared intensity-modulated radiotherapy and 3D-conformal irradiation in oropharyngeal cancers according to the requirement of dentists., Material and Methods: From the files of seven patients with cancer of the oropharynx, two dosimetry plannings for 3D-conformal radiotherapy and intensity-modulated radiotherapy with tomotherapy were performed. The dose distributions in the target volumes and organs at risk in relation to the dental sphere were compared., Results: For the planning target volume of the primitive tumour sites, average values of V95%, D2%, D98% and of the conformal index were statistically in favour of tomotherapy. For the planning target volume of node areas, averages values of V95%, D2%, D98% were statistically in favour of tomotherapy. For ipsi- and controlateral parotide glands, average values of V15Gy, V26Gy, V30Gy, V40Gy were significantly lower for tomotherapy. For the submaxillary glands, average values of mean doses and V40Gy were statistically in favour of tomotherapy. For the buccal cavity, the average values of V45Gy were statistically in favour of tomotherapy. For ipsi- and controlateral masseter muscles, the average values of mean doses were statistically in favour of tomotherapy. For the ipsi- and controlateral temporomandibular joints, average values of mean doses and V60Gy were statistically in favour of tomotherapy. For mandibular bone, average values of mean doses and V40Gy, V50Gy, V60Gy and V70Gy were statistically in favour of tomotherapy. For maxillary bone, average values of V40Gy, V50Gy and V60Gy were statistically in favour of tomotherapy., Conclusion: The radiation oncologist can constrain the intensity-modulated radiotherapy dosimetry to the needs of dentists to prevent or improve dental care and quality of life., (Copyright © 2013 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.)

Purpose: To analyze the outcome and dose distribution of intensity-modulated radiation therapy (IMRT) by helical tomotherapy in women treated for large supradiaphragmatic Hodgkin's disease., Material and Methods: A total of 13 patients received adjuvant radiation at a dose of 30 Gy to the initially involved sites with a boost of 6 Gy to those areas suspected of harboring residual disease on the simulation CT scan., Results: With a median follow-up of 23 months, the two-year progression-free survival was 91.6%, and the 2- and 3-year overall survivals were 100%. We did not report any heart or lung acute side effects. The conformity index of PTV (Planning Target Volume) was better for IMRT than for 3D-CRT (p=0.001). For the breasts, lungs, heart, thyroid and esophagus, the volume distributions favored the IMRT plans. For the breasts, the V(20Gy), V(25Gy) and V(30Gy) were 1.5, 2.5 and 3.5 times lower, respectively, for IMRT than for 3D-CRT. For the lung tissues, the V(20Gy) and V(30Gy) were 2 times and 4.5 times lower, respectively, for IMRT than for 3D-CRT. For the heart, the V(20Gy) and V(30Gy) were 1.4 and 2 times lower, respectively, for IMRT than for 3D-CRT. For the esophagus, the V(35Gy) was 1.7 lower for IMRT than for 3D-CRT, and for the thyroid, the V(30Gy) was 1.2 times lower for IMRT., Conclusion: IMRT by helical tomotherapy improved the PTV coverage and dramatically decreased the dose in organs at risk. The treatment was well tolerated, but a longer follow-up is necessary to prove a translation of these dosimetric improvements in the outcome of the patients.

Background: Intensity modulated radiotherapy is an efficient radiotherapy technique to increase dose in target volumes and decrease irradiation dose in organs at risk. This last objective is mainly relevant in children. However, previous results suggested that IMRT could increase low dose, factor of risk for secondary radiation induced cancer. This study was performed to compare dose distributions with 3D-radiotherapy (3D-RT) and IMRT with tomotherapy (HT) in children with neuroblastoma. Seven children with neuroblastoma were irradiated. Treatment plans were calculated for 3D-RT, and for HT. For the volume of interest, the PTV-V95% and conformity index were calculated. Dose constraints of all the organs at risk and integral dose were compared., Results: The conformity index was statistically better for HT than for 3D-RT. PTV-V95% constraint was reached in 6 cases with HT compared to 2 cases with 3D-RT. For the ipsilateral kidney of the tumor, the V12 Gy constraint was reached for 3 patients with both methods. The values were lower with HT than with 3D-RT in two cases and higher in one case. The threshold was not reached for one patient with either technique, but the value was lower with HT than with 3D-RT. For the contralateral kidney of the tumors, the V12 Gy constraint was reached for all patients with both methods. The values were lower with HT than with 3D-RT in 5 of 7 children, equal in one patient and higher in one patient. The organ-at-risk volumes receiving low doses were significantly lower with 3D-RT but larger for the highest doses, compared to those irradiated with HT. The integral doses were not different., Conclusions: IMRT with HT allows a better conformity treatment, a more frequently acceptable PTV-V95% than 3D-RT and, concomitantly, a better shielding of the kidneys. The integral doses are comparable between both techniques but consideration of differences in dose distribution between the two techniques, for the organs at risk, has to be taken in account when validating treatment.

Purpose: Comparison of three dosimetric techniques of lung tumor delineation to integrate tumor motion during breathing., Patients and Methods: Nineteen patients with T1-3N0M0 malignant lung tumor were treated with definitive chemoradiotherapy (14 cases) or pre-surgery chemoradiation. Doses were, respectively, 66 and 46Gy. CT-scan for delineation was performed during three phases of breathing: free breathing and deep breath-hold inspiration and expiration. GTV (gross tumor volume) was delineated on the three sequences. The classic technique included GTV from the free-breathing sequence plus a CTV (clinical target volume) margin of 5 to 8mm plus a PTV (planning target volume) margin of 7 to 10mm (including ITV [internal target volume] margin and set-up margin). The gating-like technique included GTV from the deep breath-hold inspiration sequence plus a CTV margin of 5 to 8mm plus a PTV margin of 2mm. The three-volume technique, included GTV as a result of the fusion of GTVs from the three sequences plus a CTV margin of 5 to 8mm plus a PTV margin of 2mm. Dosimetry was calculated for the three PTVs, if possible, with the same fields number and position. Dose constraints and rules were imposed to accept dosimetries: firstly spinal cord maximal dose less than 45Gy, followed by V95 % for PTV greater than or equal to 95 %, and V20 GY(Gy) for lung less than or equal to 30 %, V30 GY(Gy) for lung less than or equal to 20 %., Results: GTVs were not statistically different between the three methods of delineation. PTVs were significantly lower with the gating-like technique. V95% of the PTV were not different between the three techniques. With the classic-, the gating-like- and the 3-volume techniques, dosimetry was considered as acceptable, respectively in 15, 18 and 15 cases. Comparisons of constraint values showed that the gating-like method gave the best results. In the case of pre-operative management, the gating-like method allowed the best results even for the V95% values. However, in the absence of gating device or without the possibility to use it, the 3-volume method allowed to take into account more precisely the organ motion than the classical technique., Conclusion: The 3-volume method can be done. It is a good method to take into account the organ motions. However, the gating-like method gives the best results leading to propose its use even for pre-operative patients with upper tumors., (2009. Published by Elsevier SAS.)

Since ten years, lung cancer radiotherapy improved thanks to capacities of imagery, softwares, hardwares which allowed developing and transforming drastically radiotherapy procedures. Improvements were performed in all steps of the lung treatment, immobilization, three dimensional imagery, delineation of the targets and organs at risk, simulation and ballistic, dose calculation, daily set-up, breathing control, and treatment verifications. Furthermore, new technology implies technical adjustments but also a change of physicians and physicists minds.

Sulphated acrylic polymers have been synthesised and evaluated as potential inhibitors of basic fibroblast growth factor-dependent cell growth. The polymers were synthesised with a range of molar masses using both a thermal radical method and a room temperature reduction activation route. The polymers had bimodal molar mass distributions, but much of the low molar mass component could be removed by dialysis. Some of these polymers were effective inhibitors, their effectiveness being dependent on the molar mass. IC50 values as low as 5 microg/ml could be obtained with up to 73% inhibition by 100 microg/ml. These polymers are of interest as potentially readily accessible materials for cancer therapy.

The various morphological and functional changes produced by lithium gluconate treatment of Mouse thyroid and ultimobranchial cells show complex interactions, involving direct and indirect effects. In most of the cases these effects determine metabolism (thyroid cells) or differentiation (ultimobranchial cell) disturbances. In most of the cases analysed changes do not concern the whole gland and should not have important consequences on its general activity-so it is more likely that at low concentration the effects of lithium gluconate on the thyroid gland of manic depressive patients might be neglected at the level of the functional state of the whole gland.

The fetal and postnatal activity patterns of different hydrolytic enzymes (alkaline phosphatase, gamma-glutamyltransferase, trehalase, maltase, glucoamylase, lactase, and sucrase) have been examined in mouse renal homogenates. Alkaline phosphatase and gamma-glutamyltransferase activities presented approximately similar changes. They increased from 18 days of gestation up to 30 days after birth. These activities showed marked increases during the 3rd and 4th postnatal weeks. A similar important rise was observed for trehalase activity at the end of the suckling period. Maltase activity increased gradually after birth. Traces of lactase, sucrase, and glucoamylase activities were detected at each developmental stage.