Review of photon and proton radiotherapy for skull base tumours

An extremely large variety of benign and malignant tumours occur at skull base; these tumour lesions are in the proximity to structures deputed to relevant physiologic functions, limiting extensive surgical approaches to this body district. Most recent progresses of surgery and radiotherapy have allowed to improve local control with acceptable rates of side effects. Various photon radiotherapy techniques are employed, including 3-dimensional conformal radiotherapy, intensity modulated radiotherapy (IMRT), stereotactic radiotherapy (SRT) and brachytherapy that is manly limited to the treatment of primary or recurrent nasopharyngeal carcinoma. Proton beam radiotherapy is also extensively used thanks to its physical characteristics. Our review, focusing in particular on meningioma, chordoma, and chondrosarcoma, suggests that proton therapy plays a major role in the treatment of malignant tumours whereas photon therapy still plays a relevant role in the treatment of benign tumour lesions

Brainstem NTCP and dose constraints for carbon ion RT—Application and translation from Japanese to European RBE-weighted dose

Background and Purpose: The Italian National Center of Oncological Hadrontherapy (CNAO) has applied dose constraints for carbon ion RT (CIRT) as defined by Japan’s National Institute of Radiological Sciences (NIRS). However, these institutions use different models to predict the relative biological effectiveness (RBE). CNAO applies the Local Effect Model I (LEM I), which in most clinical situations predicts higher RBE than NIRS’s Microdosimetric Kinetic Model (MKM). Equal constraints therefore become more restrictive at CNAO. Tolerance doses for the brainstem have not been validated for LEM I-weighted dose (DLEM I). However, brainstem constraints and a Normal Tissue Complication Probability (NTCP) model were recently reported for MKM-weighted dose (DMKM), showing that a constraint relaxation to DMKM|0.7 cm3 <30 Gy (RBE) and DMKM|0.1 cm3 <40 Gy (RBE) was feasible. The aim of this work was to evaluate the brainstem NTCP associated with CNAO’s current clinical practice and to propose new brainstem constraints for LEM I-optimized CIRT at CNAO. Material and Methods: We reproduced the absorbed dose of 30 representative patient treatment plans from CNAO. Subsequently, we calculated both DLEM I and DMKM, and the relationship between DMKM and DLEM I for various brainstem dose metrics was analyzed. Furthermore, the NTCP model developed for DMKM was applied to estimate the NTCPs of the delivered plans. Results: The translation of CNAO treatment plans to DMKM confirmed that the former CNAO constraints were conservative compared with DMKM constraints. Estimated NTCPs were 0% for all but one case, in which the NTCP was 2%. The relationship DMKM/DLEM I could be described by a quadratic regression model which revealed that the validated DMKM constraints corresponded to DLEM I|0.7 cm3 <41 Gy (RBE) (95% CI, 38–44 Gy (RBE)) and DLEM I|0.1 cm3 <49 Gy (RBE) (95% CI, 46–52 Gy (RBE)). Conclusion: Our study demonstrates that RBE-weighted dose translation is of crucial importance in order to exchange experience and thus harmonize CIRT treatments globally. To mitigate uncertainties involved, we propose to use the lower bound of the 95% CI of the translation estimates, i.e., DLEM I|0.7 cm3 <38 Gy (RBE) and DLEM I|0.1 cm3 <46 Gy (RBE) as brainstem dose constraints for 16 fraction CIRT treatments optimized with LEM I.publishedVersio

Normofractionated and moderately hypofractionated proton therapy: Comparison of acute toxicity and early quality of life outcomes

Aim Data on the safety of moderately hypofractionated proton beam therapy (PBT) are limited. The aim of this study is to compare the acute toxicity and early quality of life (QoL) outcomes of normofractionated (nPBT) and hypofractionated PBT (hPBT). Results Overall, the highest toxicity grades of G0, G1, G2, and G3 were observed in 7 (5%), 40 (28.8%), 78 (56.1%), and 15 (10.8%) patients, respectively. According to organ and site, no statistically significant differences were detected in the majority of toxicity comparisons (66.7%). For A&P, hPBT showed a more favorable toxicity profile as compared to nPBT with a higher frequency of G0 and G1 and a lower frequency of G2 and G3 events (p = 0.04), more patients with improvement (95.7% vs 70%, p = 0.023), and full resolution of toxicities (87% vs 50%, p = 0.008). Skin toxicity was unanimously milder for hPBT compared to nPBT in A&P and ST locations (p = 0.018 and p = 0.025, respectively). No significant differences in QoL were observed in 97% of comparisons for QLQ-C30 scale except for loss of appetite in H&N patients (+33.3 for nPBT and 0 for hPBT, p = 0.02) and role functioning for A&P patients (0 for nPBT vs +16.7 hPBT, p = 0.003). For QLQ-HN35, 97.9% of comparisons did not reveal significant differences, with pain as the only scale varying between the groups (-8.33 vs -25, p = 0.016). Conclusion Hypofractionated proton therapy offers non-inferior early safety and QoL as compared to normofractionated irradiation and warrants further clinical investigation

Phase I/II trial evaluating carbon ion radiotherapy for the treatment of recurrent rectal cancer: the PANDORA-01 trial

<p>Abstract</p> <p>Background</p> <p>Treatment standard for patients with rectal cancer depends on the initial staging and includes surgical resection, radiotherapy as well as chemotherapy. For stage II and III tumors, radiochemotherapy should be performed in addition to surgery, preferentially as preoperative radiochemotherapy or as short-course hypofractionated radiation. Advances in surgical approaches, especially the establishment of the total mesorectal excision (TME) in combination with sophisticated radiation and chemotherapy have reduced local recurrence rates to only few percent. However, due to the high incidence of rectal cancer, still a high absolute number of patients present with recurrent rectal carcinomas, and effective treatment is therefore needed.</p> <p>Carbon ions offer physical and biological advantages. Due to their inverted dose profile and the high local dose deposition within the Bragg peak precise dose application and sparing of normal tissue is possible. Moreover, in comparison to photons, carbon ions offer an increase relative biological effectiveness (RBE), which can be calculated between 2 and 5 depending on the cell line as well as the endpoint analyzed.</p> <p>Japanese data on the treatment of patients with recurrent rectal cancer previously not treated with radiation therapy have shown local control rates of carbon ion treatment superior to those of surgery. Therefore, this treatment concept should also be evaluated for recurrences after radiotherapy, when dose application using conventional photons is limited. Moreover, these patients are likely to benefit from the enhanced biological efficacy of carbon ions.</p> <p>Methods and design</p> <p>In the current Phase I/II-PANDORA-01-Study the recommended dose of carbon ion radiotherapy for recurrent rectal cancer will be determined in the Phase I part, and feasibilty and progression-free survival will be assessed in the Phase II part of the study.</p> <p>Within the Phase I part, increasing doses from 12 × 3 Gy E to 18 × 3 Gy E will be applied.</p> <p>The primary endpoint in the Phase I part is toxicity, the primary endpoint in the Phase II part is progression-free survival.</p> <p>Discussion</p> <p>With conventional photon irradiation treatment of recurrent rectal cancer is limited, and the clinical effect is only moderate. With carbon ions, an improved outcome can be expected due to the physical and biological characteristics of the carbon ion beam. However, the optimal dose applicable in this clincial situation as re-irradiation still has to be determined. This, as well as efficacy, is to be evaluated in the present Phase I/II trial.</p> <p>Trial registration</p> <p><a href="http://www.clinicaltrials.gov/ct2/show/NCT01528683">NCT01528683</a></p

The sacral chordoma margin

[Objective]: Aim of the manuscript is to discuss how to improve margins in sacral chordoma. [Background]: Chordoma is a rare neoplasm, arising in half cases from the sacrum, with reported local failure in >50% after surgery. [Methods]: A multidisciplinary meeting of the “Chordoma Global Consensus Group” was held in Milan in 2017, focusing on challenges in defining and achieving optimal margins in chordoma with respect to surgery, definitive particle radiation therapy (RT) and medical therapies. This review aims to report on the outcome of the consensus meeting and to provide a summary of the most recent evidence in this field. Possible new ways forward, including on-going international clinical studies, are discussed. [Results]: En-bloc tumor-sacrum resection is the cornerstone of treatment of primary sacral chordoma, aiming to achieve negative microscopic margins. Radical definitive particle therapy seems to offer a similar outcome compared to surgery, although confirmation in comparative trials is lacking; besides there is still a certain degree of technical variability across institutions, corresponding to different fields of treatment and different tumor coverage. To address some of these questions, a prospective, randomized international study comparing surgery versus definitive high-dose RT is ongoing. Available data do not support the routine use of any medical therapy as (neo)adjuvant/cytoreductive treatment. [Conclusion]: Given the significant influence of margins status on local control in patients with primary localized sacral chordoma, the clear definition of adequate margins and a standard local approach across institutions for both surgery and particle RT is vital for improving the management of these patients

Rituximab versus tocilizumab in rheumatoid arthritis: synovial biopsy-based biomarker analysis of the phase 4 r4ra randomized trial

Patients with rheumatoid arthritis (RA) receive highly targeted biologic therapies without previous knowledge of target expression levels in the diseased tissue. Approximately 40% of patients do not respond to individual biologic therapies and 5–20% are refractory to all. In a biopsy-based, precision-medicine, randomized clinical trial in RA (R4RA; n = 164), patients with low/absent synovial B cell molecular signature had a lower response to rituximab (anti-CD20 monoclonal antibody) compared with that to tocilizumab (anti-IL6R monoclonal antibody) although the exact mechanisms of response/nonresponse remain to be established. Here, in-depth histological/molecular analyses of R4RA synovial biopsies identify humoral immune response gene signatures associated with response to rituximab and tocilizumab, and a stromal/fibroblast signature in patients refractory to all medications. Post-treatment changes in synovial gene expression and cell infiltration highlighted divergent effects of rituximab and tocilizumab relating to differing response/nonresponse mechanisms. Using ten-by-tenfold nested cross-validation, we developed machine learning algorithms predictive of response to rituximab (area under the curve (AUC) = 0.74), tocilizumab (AUC = 0.68) and, notably, multidrug resistance (AUC = 0.69). This study supports the notion that disease endotypes, driven by diverse molecular pathology pathways in the diseased tissue, determine diverse clinical and treatment–response phenotypes. It also highlights the importance of integration of molecular pathology signatures into clinical algorithms to optimize the future use of existing medications and inform the development of new drugs for refractory patients

Echoes of 1968 in an elementary school of Genoa

In the archive of a primary school in Genoa documents have been found that were about to be destroyed. They are 435 reports, written by 145 teachers (males and females) in compliance with the law 24.12.1957 n. 125 on the pupils’ failure to be admitted to the higher class. These reports date back to the period extending from 1960 to 1979, although none of them refers to the school years 1966-67, 1975-76, 1976-77. This period includes famous 1968 and the years when the Collegiate Bodies were established.In this paper I investigate whether the analysis of these documents shows how and to which extent the dramatic events of that time have influenced the way of teaching and the policies adopted by these elementary teachers on the selection of pupils, the recovery of difficult children, full-time schooling, and the involvement of families in school life. In some cases I am able to relate the reports on failed admission to the higher class to the activity of the Collegiate Bodies in the school

Tumour seeding in the surgical pathway after resection of skull base chordoma

AimThe aim of this study is to review the clinical series in which tumour seeding was reported after skull base surgery for chordomas.BackgroundThe occurrence of implantation of cancer cells during surgical procedures for the removal of chordoma is a rare event described by a number of authors in a few patient series and case reports.Materials and methodsLiterature search was performed by PubMed and Scopus by using the words “surgical tumour seeding, tumour implantation, surgical pathway recurrence, skull base chordoma, and clivus chordoma”.ResultsSix retrospective series and 7 case reports were included in the analysis. In total, 34 patients are described with pathway recurrence, 30 at a single site and 4 at multiple sites.In the 5 largest chordoma series, the rate of occurrence of surgical seeding ranged from 1.3% to 7.3% (3.9%). In the 34 patients diagnosed with tumour seeding, the most frequent surgical approach was trans-nasal/trans-sphenoidal, that was used in 12 cases. The median time from primary treatment to surgical pathway tumour seeding ranged from 7 to 78 months. Data of the treatment of seeding are available in 26/34 patients. All of them underwent a new surgery, 6 received additional external beam radiotherapy, and 2 intraoperative radiotherapy.ConclusionsThe risk of surgical seeding should be taken into consideration when deciding on the surgical approach and the planning treatment volume for postoperative radiation therapy. The surgical pathway should be included in follow-up studies to diagnose this peculiar type of treatment failure possibly at an early phase

Tumour seeding in the surgical pathway after resection of skull base chordoma

AIM: The aim of this study is to review the clinical series in which tumour seeding was reported after skull base surgery for chordomas. BACKGROUND: The occurrence of implantation of cancer cells during surgical procedures for the removal of chordoma is a rare event described by a number of authors in a few patient series and case reports. MATERIALS AND METHODS: Literature search was performed by PubMed and Scopus by using the words "surgical tumour seeding, tumour implantation, surgical pathway recurrence, skull base chordoma, and clivus chordoma". RESULTS: Six retrospective series and 7 case reports were included in the analysis. In total, 34 patients are described with pathway recurrence, 30 at a single site and 4 at multiple sites. In the 5 largest chordoma series, the rate of occurrence of surgical seeding ranged from 1.3% to 7.3% (3.9%). In the 34 patients diagnosed with tumour seeding, the most frequent surgical approach was trans-nasal/trans-sphenoidal, that was used in 12 cases. The median time from primary treatment to surgical pathway tumour seeding ranged from 7 to 78 months. Data of the treatment of seeding are available in 26/34 patients. All of them underwent a new surgery, 6 received additional external beam radiotherapy, and 2 intraoperative radiotherapy. CONCLUSIONS: The risk of surgical seeding should be taken into consideration when deciding on the surgical approach and the planning treatment volume for postoperative radiation therapy. The surgical pathway should be included in follow-up studies to diagnose this peculiar type of treatment failure possibly at an early phase

preliminary calculation of rbe weighted dose distribution for cerebral radionecrosis in carbon ion treatment planning

Carbon-ion radiotherapy/Cerebral radionecrosis/RBE-weighted dose/Microdosimetry. Cerebral radionecrosis is a significant side effect in radiotherapy for brain cancer. The purpose of th is study is to calculate the relative biological effectiveness (RBE) of carbon-ion beams on brain cells and to show RBE-weighted dose distributions for cerebral radionecrosis speculation in a carbon-ion treatment planning system. The RBE value of the radionecrosis for the carbon-ion beam is calculated by the modified microdosimetric kinetic model on the as sumption of a typical clinical α/β ratio of 2 Gy for cerebral radionecrosis in X-rays. This calculation method for the RBE-weighted dose is built into the treatment planning system for the carbon-ion radiotherapy. The RBE-weighted dose distributions are calculated on computed tomography (CT) images of four patients who had been treated by carbon-ion radiotherapy for astrocytoma (WHO grade 2) and who suffered from necrosis around the target areas. The necrotic areas were detected by brain scans via magnetic resonance imaging (MRI) after the treatment irradiation. The detected necrotic areas are easily found near high RBE-weighted dose regions. The visual comparison between the RBE-weighted dose distribution and the necrosis region indicates that the RBE-weighted dose distribution will be helpful information for the prediction of radionecrosis areas after carbon-ion radiotherapy