Purpose
Only few centers worldwide treat intraocular tumors with proton therapy, all of them with a dedicated beamline, except in one case in the USA. The Italian National Center for Oncological ...Hadrontherapy (CNAO) is a synchrotron‐based hadrontherapy facility equipped with fixed beamlines and pencil beam scanning modality. Recently, a general‐purpose horizontal proton beamline was adapted to treat also ocular diseases. In this work, the conceptual design and main dosimetric properties of this new proton eyeline are presented.
Methods
A 28 mm thick water‐equivalent range shifter (RS) was placed along the proton beamline to shift the minimum beam penetration at shallower depths. FLUKA Monte Carlo (MC) simulations were performed to optimize the position of the RS and patient‐specific collimator, in order to achieve sharp lateral dose gradients. Lateral dose profiles were then measured with radiochromic EBT3 films to evaluate the dose uniformity and lateral penumbra width at several depths. Different beam scanning patterns were tested. Discrete energy levels with 1 mm water‐equivalent step within the whole ocular energy range (62.7–89.8 MeV) were used, while fine adjustment of beam range was achieved using thin polymethylmethacrylate additional sheets.
Depth‐dose distributions (DDDs) were measured with the Peakfinder system. Monoenergetic beam weights to achieve flat spread‐out Bragg Peaks (SOBPs) were numerically determined. Absorbed dose to water under reference conditions was measured with an Advanced Markus chamber, following International Atomic Energy Agency (IAEA) Technical Report Series (TRS)‐398 Code of Practice. Neutron dose at the contralateral eye was evaluated with passive bubble dosimeters.
Results
Monte Carlo simulations and experimental results confirmed that maximizing the air gap between RS and aperture reduces the lateral dose penumbra width of the collimated beam and increases the field transversal dose homogeneity. Therefore, RS and brass collimator were placed at about 98 cm (upstream of the beam monitors) and 7 cm from the isocenter, respectively. The lateral 80%–20% penumbra at middle‐SOBP ranged between 1.4 and 1.7 mm depending on field size, while 90%–10% distal fall‐off of the DDDs ranged between 1.0 and 1.5 mm, as a function of range. Such values are comparable to those reported for most existing eye‐dedicated facilities. Measured SOBP doses were in very good agreement with MC simulations. Mean neutron dose at the contralateral eye was 68 μSv/Gy. Beam delivery time, for 60 Gy relative biological effectiveness (RBE) prescription dose in four fractions, was around 3 min per session.
Conclusions
Our adapted scanning proton beamline satisfied the requirements for intraocular tumor treatment. The first ocular treatment was delivered in August 2016 and more than 100 patients successfully completed their treatment in these 2 yr.
Pancreatic adenocarcinoma is a high-mortality neoplasm with a documented 5-years-overall survival around 5%. In the last decades, a real breakthrough in the treatment of the disease has not been ...achieved. Here we propose a prospective, phase II, multicentre, single-arm study aiming to assess the efficacy and the feasibility of a therapeutic protocol combining chemotherapy, carbon ion therapy and surgery for resectable and borderline resectable pancreatic adenocarcinoma.
The purpose of this trial (PIOPPO Protocol) is to assess the efficacy and the feasibility of 3 cycles of FOLFIRINOX neoadjuvant chemotherapy followed by a short-course of carbon ion radiotherapy (CIRT) for resectable or borderline resectable pancreatic adenocarcinoma patients. Primary outcome of this study is the assessment of local progression free survival (L-PFS). The calculation of sample size is based on the analysis of the primary endpoint "progression free survival" according to Fleming's Procedure.
Very preliminary results provide initial evidence of the feasibility of the combined chemotherapy and CIRT in the neoadjuvant setting for resectable or borderline resectable pancreatic cancer. Completion of the accrual and long term results are awaited to see if this combination of treatment is advisable and will provide the expected benefits.
ClinicalTrials.gov Identifier: NCT03822936 registered on January 2019.
Abstract
Background
The aim of this study is to evaluate results in terms of local control (LC), overall survival (OS), and toxicity profile and to better identify factors influencing clinical ...outcome of skull base chordoma treated with proton therapy (PT) and carbon ion radiotherapy (CIRT).
Methods
We prospectively collected and analyzed data of 135 patients treated between November 2011 and December 2018. Total prescription dose in the PT group (70 patients) and CIRT group (65 patients) was 74 Gy relative biological effectiveness (RBE) delivered in 37 fractions and 70.4 Gy(RBE) delivered in 16 fractions, respectively (CIRT in unfavorable patients). LC and OS were evaluated using the Kaplan–Meier method. Univariate and multivariate analyses were performed, to identify prognostic factors on clinical outcomes.
Results
After a median follow-up of 49 (range, 6–87) months, 14 (21%) and 8 (11%) local failures were observed in CIRT and PT group, respectively. Five-year LC rate was 71% in CIRT cohort and 84% in PT cohort. The estimated 5-year OS rate in the CIRT and PT group was 82% and 83%, respectively. On multivariate analysis, gross tumor volume (GTV), optic pathways, and/or brainstem compression and dose coverage are independent prognostic factors of local failure risk. High rate toxicity grade ≥3 was reported in 11% of patients.
Conclusions
Particle radiotherapy is an effective treatment for skull base chordoma with acceptable late toxicity. GTV, optic pathways, and/or brainstem compression and target coverage were independent prognostic factors for LC.
Key Points
• Proton and carbon ion therapy are effective and safe in skull base chordoma.
• Prognostic factors are GTV, organs at risk compression, and dose coverage.
• Dual particle therapy and customized strategy was adopted.
Background and Objectives
Selection of patients affected by pelvic recurrence of rectal cancer (PRRC) who are likely to achieve a R0 resection is mandatory. The aim of this study was to propose a ...classification for PRRC to predict both radical surgery and disease‐free survival (DFS).
Methods
PRRC patients treated at the National Cancer Institute of Milan (Italy) were included in the study. PRRC were classified as S1, if located centrally (S1a‐S1b) or anteriorly (S1c) within the pelvis; S2, in case of sacral involvement below (S2a) or above (S2b) the second sacral vertebra; S3, in case of lateral pelvic involvement.
Results
Of 280 reviewed PRRC patients, 152 (54.3%) were evaluated for curative surgery. The strongest predictor of R+ resection was the S3 category (OR, 6.37; P = .011). Abdominosacral resection (P = .012), anterior exenteration (P = .012) and extended rectal re‐excision (P = .003) were predictive of R0 resection. S3 category was highly predictive of poor DFS (HR 2.53; P = .038). DFS was significantly improved after R0 surgery for S1 (P < .0001) and S2 (P = .015) patients but not for S3 cases (P = .525).
Conclusions
The proposed classification allows selection of subjects candidates to curative surgery, emphasizing that lateral pelvic involvement is the main predictor of R+ resection and independently affects the DFS.
Highlights•mMKM to LEM conversion of dose prescription/constraints affects treatment outcomes. •LEM-68.8 Gy(RBE) correctly reproduces mMKM-64 Gy(RBE) for ACC patients. •ACC relapses were mainly ...related to CTV under-dosage due to OARs sparing. •mMKM OARs constraints require correction when applied to LEM plans.
Skull-base chordoma (SBC) can be treated with carbon ion radiotherapy (CIRT) to improve local control (LC). The study aimed to explore the role of multi-parametric radiomic, dosiomic and clinical ...features as prognostic factors for LC in SBC patients undergoing CIRT. Before CIRT, 57 patients underwent MR and CT imaging, from which tumour contours and dose maps were obtained. MRI and CT-based radiomic, and dosiomic features were selected and fed to two survival models, singularly or by combining them with clinical factors. Adverse LC was given by in-field recurrence or tumour progression. The dataset was split in development and test sets and the models' performance evaluated using the concordance index (C-index). Patients were then assigned a low- or high-risk score. Survival curves were estimated, and risk groups compared through log-rank tests (after Bonferroni correction α = 0.0083). The best performing models were built on features describing tumour shape and dosiomic heterogeneity (median/interquartile range validation C-index: 0.80/024 and 0.79/0.26), followed by combined (0.73/0.30 and 0.75/0.27) and CT-based models (0.77/0.24 and 0.64/0.28). Dosiomic and combined models could consistently stratify patients in two significantly different groups. Dosiomic and multi-parametric radiomic features showed to be promising prognostic factors for LC in SBC treated with CIRT.
Background
The standard approach for locally advanced rectal cancer (LARC) is neoadjuvant chemoradiotherapy (nCRT) followed by total mesorectal excision (TME). After nCRT 20% of patients achieve a ...clinical complete response (pCR) and could be treated with a non-operative management (NOM).
Methods
The panel of the Italian Association of Medical Oncology (AIOM) Guidelines on rectal cancer applied the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach addressing the following question: Should NOM vs. TME be used for patients with rectal cancer with clinical complete response after nCRT? Five outcomes were identified: disease-free survival (DFS), mortality, local recurrence, colostomy rate, and functional outcomes.
Results
Nine studies were included in the analysis. A higher risk of disease recurrence was observed in the NOM group compared to the TME group (RR = 1.69, 95% CI 1.08, 2.64) on the other hand, we observed a slightly positive but not significant effect on mortality of NOM (RR = 0.82, 95% CI 0.46, 1.45). Patients in the NOM group were more likely to experience local recurrence (RR = 5.37, 95% CI 2.56, 11.27) and patients in the TME group were more likely to have a permanent colostomy (RR = 0.15, 95% CI 0.08, 0.29). Only one study evaluated functional outcomes. The overall certainty of evidence was rated as very low.
Conclusions
NOM was found to correlate with a higher risk of local recurrence which did not translate in worse OS and a lower colostomy rate. Due to the paucity of evidences, no recommendations are possible. NOM remains an experimental treatment; thus, patients managed with NOM should be enrolled in clinical trials with a dedicated follow-up schedule.
Background
Skull base chordomas (SBC) are rare malignant tumors and few factors have been found to be reliable markers for clinical decision making and survival prognostication. The aim of the ...present work was to identify specific prognostic factors potentially useful for the management of SBC patients.
Methods
A retrospective review of all the patients diagnosed and treated for SBC at the Fondazione IRCCS Istituto Neurologico “Carlo Besta” between January 1992 and December 2017 has been performed. Survival analysis was performed and a logistic regression model was used. Statistically significant predictors were rated based on their log odds in order to preliminarily build a personalized grading scale—the Peri-Operative Chordoma Scale (POCS).
Results
Fifty-nine primary chordoma patients were included. The average follow-up from the first treatment was 82.6 months (95% CI, 65.5–99.7). POCS was built over PFS and MR contrast enhancement (intense vs mild/no, value 4), preoperative motor deficit (yes vs no, value 3), and the development of any postoperative complications (yes vs no, value 2). POCS ranges between 0 and 9, with higher scores being associated with reduced likelihood of survival and progression-free state.
Conclusions
Our results show that preoperative clinical symptoms (motor deficits), surgical features (extent of tumor resection and surgeon’s experience), development of postoperative complications, and KPS decline represent significant prognostic factors. The degree of MR contrast enhancement significantly correlated to both OS and PFS. We also preliminarily developed the POCS as a prognostic grading scale which may help neurosurgeons in the personalized management of patients undergoing potential adjuvant therapies.
To evaluate the efficacy of sodium butyrate enemas (NABUREN) in prostate cancer radiation therapy (RT) in reducing the incidence, severity, and duration of acute RT-induced proctitis.
166 patients, ...randomly allocated to 1 of 4 groups (rectal sodium butyrate 1 g, 2 g, or 4 g daily or placebo), were treated with NABUREN during and 2 weeks after RT. The grade of proctitis was registered in a daily diary. The correlation between NABUREN and proctitis was investigated through χ(2) statistics. The toxicity endpoints considered were as follows: total number of days with grade ≥1 proctitis (≥G1); total number of days with grade ≥2 proctitis (≥G2); ≥G1 and ≥G2 proctitis lasting at least 3 and 5 consecutive days starting from week 4 (≥G1+3d, ≥G2+3d); damaging effects of RT on rectal mucosa as measured by endoscopy. The relationship between endpoints and pretreatment morbidities, hormonal therapy, presence of diabetes or hypertension, abdominal surgery, or hemorrhoids was investigated by univariate analysis.
The patients were randomly allocated to the 4 arms. No difference in the distribution of comorbidities among the arms was observed (P>.09). The mean ≥G1 and ≥G2 proctitis were 7.8 and 4.9 for placebo and 8.9 and 4.7 for the NABUREN group, respectively. No favorable trend in reduction of incidence, severity, and duration of ≥G1 and ≥G2 proctitis was observed with NABUREN use. In univariate analysis, ≥G1+3d toxicity was found to be related to hemorrhoids (P=.008), and a slight correlation was found between ≥G2 proctitis and hormonal therapy (P=.06). The RT effects on rectal mucosa as based on endoscopic assessment were mainly related to diabetes (P<.01). Endoscopy data at 6 week showed no significant difference between the placebo and butyrate arms. The other investigated endpoints were not correlated with any of the clinical risk factors analyzed.
There was no evidence of efficacy of NABUREN in reducing the incidence, severity, and duration of acute radiation proctitis. There was a correlation between some endpoints and clinical risk factors.
Some cancers such as sarcomas (bone and soft tissue sarcomas) and adenoid cystic carcinomas are considered as radioresistant to low linear energy transfer radiation (including photons and protons) ...and may therefore beneficiate from a carbon ion therapy. Despite encouraging results obtained in phase I/II trials compared to historical data with photons, the spread of carbon ions has been limited mainly because of the absence of randomized medical data. The French health authorities stressed the importance of having randomized data for carbon ion therapy.
The ETOILE study is a multicenter prospective randomized phase III trial comparing carbon ion therapy to either advanced photon or proton radiotherapy for inoperable or macroscopically incompletely resected (R2) radioresistant cancers including sarcomas and adenoid cystic carcinomas. In the experimental arm, carbon ion therapy will be performed at the National Center for Oncological Hadrontherapy (CNAO) in Pavia, Italy. In the control arm, photon or proton radiotherapy will be carried out in referent centers in France. The primary endpoint is progression-free survival (PFS). Secondary endpoints are overall survival and local control, toxicity profile, and quality of life. In addition, a prospective health-economic study and a radiobiological analysis will be conducted. To demonstrate an absolute improvement in the 5-year PFS rate of 20% in favor of carbon ion therapy, 250 patients have to be included in the study.
So far, no clinical study of phase III has demonstrated the superiority of carbon ion therapy compared to conventional radiotherapy, including proton therapy, for the treatment of radioresistant tumors.
ClinicalTrials.gov identifier: NCT02838602 . Date of registration: July 20, 2016. The posted information will be updated as needed to reflect protocol amendments and study progress.
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