Objective: To compare radiation-induced toxicity and dosimetry parameters in patients with locally advanced nasopharyngeal cancer (LANPC) treated with a mixed-beam (MB) approach (IMRT followed by proton therapy boost) with an historic cohort of patients treated with a full course of IMRT-only. Material and methods: Twenty-seven patients with LANPC treated with the MB approach were compared to a similar cohort of 17 patients treated with IMRT-only. The MB approach consisted in a first phase of IMRT up to 54–60 Gy followed by a second phase delivered with a proton therapy boost up to 70–74 Gy (RBE). The total dose for patients treated with IMRT-only was 69.96 Gy. Induction chemotherapy was administrated to 59 and 88% and concurrent chemoradiotherapy to 88 and 100% of the MB and IMRT-only patients, respectively. The worst toxicity occurring during the entire course of treatment (acute toxicity) and early-late toxicity were registered according to the Common Terminology Criteria Adverse Events V4.03. Results: The two cohorts were comparable. Patients treated with MB received a significantly higher median total dose to target volumes (p = .02). Acute grade 3 mucositis was found in 11 and 76% (p = .0002) of patients treated with MB and IMRT-only approach, respectively, while grade 2 xerostomia was found in 7 and 35% (p = .02) of patients treated with MB and IMRT-only, respectively. There was no statistical difference in late toxicity. Local progression-free survival (PFS) and progression-free survival curves were similar between the two cohorts of patients (p = .17 and p = .40, respectively). Local control rate was 96% and 81% for patients treated with MB approach and IMRT-only, respectively. Conclusions: Sequential MB approach for LANPC patients provides a significantly lower acute toxicity profile compared to full course of IMRT. There were no differences in early-late morbidities and disease-related outcomes (censored at two-years) but a longer follow-up is required to achieve conclusive results.
Background: Currently, 13 Asian and European facilities deliver carbon ion radiotherapy (CIRT) for preclinical and clinical activity, and, to date, 55 clinical studies including CIRT for adult and paediatric solid neoplasms have been registered. The National Center for Oncological Hadrontherapy (CNAO) is the only Italian facility able to accelerate both protons and carbon ions for oncological treatment and research. Methods: To summarise and critically evaluate state-of-the-art knowledge on the application of carbon ion radiotherapy in oncological settings, the authors conducted a literature search till December 2022 in the following electronic databases: PubMed, Web of Science, MEDLINE, Google Scholar, and Cochrane. The results of 68 studies are reported using a narrative approach, highlighting CNAO’s clinical activity over the last 10 years of CIRT. Results: The ballistic and radiobiological hallmarks of CIRT make it an effective option in several rare, radioresistant, and difficult-to-treat tumours. CNAO has made a significant contribution to the advancement of knowledge on CIRT delivery in selected tumour types. Conclusions: After an initial ramp-up period, CNAO has progressively honed its clinical, technical, and dosimetric skills. Growing engagement with national and international networks and research groups for complex cancers has led to increasingly targeted patient selection for CIRT and lowered barriers to facility access.
(1) Background: we proposed an integrated strategy to support clinical allocation of nasopharyngeal patients between proton and photon radiotherapy. (2) Methods: intensity-modulated proton therapy (IMPT) plans were optimized for 50 consecutive nasopharyngeal carcinoma (NPC) patients treated with volumetric modulated arc therapy (VMAT), and differences in dose and normal tissue complication probability (ΔNTCPx-p) for 16 models were calculated. Patient eligibility for IMPT was assessed using a model-based selection (MBS) strategy following the results for 7/16 models describing the most clinically relevant endpoints, applying a model-specific ΔNTCPx-p threshold (15% to 5% depending on the severity of the complication) and a composite threshold (35%). In addition, a comprehensive toxicity score (CTS) was defined as the weighted sum of all 16 ΔNTCPx-p, where weights follow a clinical rationale. (3) Results: Dose deviations were in favor of IMPT (ΔDmean ≥ 14% for cord, esophagus, brainstem, and glottic larynx). The risk of toxicity significantly decreased for xerostomia (−12.5%), brain necrosis (−2.3%), mucositis (−3.2%), tinnitus (−8.6%), hypothyroidism (−9.3%), and trismus (−5.4%). There were 40% of the patients that resulted as eligible for IMPT, with a greater advantage for T3–T4 staging. Significantly different CTS were observed in patients qualifying for IMPT. (4) Conclusions: The MBS strategy successfully drives the clinical identification of NPC patients, who are most likely to benefit from IMPT. CTS summarizes well the expected global gain.
The purpose of our study was to analyze the role of [(11)C]choline-positron emission tomography/computed tomography (cho-PET/CT) in the management of patients with prostate cancer referred for radiotherapy. Inclusion criteria for this retrospective study were (1) presence of prostate cancer, (2) referral for first radiotherapy course (for primary or recurrent tumor) between February 2007 and July 2010, and (3) performance of cho-PET/CT. All cho-PET/CT scans were classified according to whether they were positive in the prostate/prostate bed (T), pelvic lymph nodes (N), and distant metastases (M) or negative. Therapeutic strategy based on the cho-PET/CT evaluation was compared with the strategy that would have been proposed had cho-PET/CT imaging not been available, following international and national prostate cancer guidelines. Eighty-two cho-PET/CT scans performed in 74 patients were analyzed. Cho-PET/CT was positive in 49 studies (60%): T only in 22 (45% of all positive studies); N only in 4 (8%); T in combination with N in 3 (6%); and M in combination with T or N, or both, in 16 (33%). Treatment after positive cho-PET/CT examination included radiotherapy ± androgen deprivation (29 patients), surgery ± radiotherapy (6 patients), androgen deprivation only (8 patients), and other treatment (6 patients). In 22 cases, cho-PET/CT (27%) altered the treatment approach compared with the treatment that would have been adopted in the absence of cho-PET/CT analysis. Cho-PET/CT is valuable in defining the extent of disease and supporting therapeutic decisions in the management of prostate cancer. The therapeutic strategy turned out to be influenced by cho-PET/CT imaging in about one third of the patients included in this study.
The growing interest in proton therapy (PT) in recent decades is justified by the evidence that protons dose distribution allows maximal dose release at the tumor depth followed by sharp distal dose fall-off. But, in the holistic management of head and neck cancer (HNC), limiting the potential of PT to a mere dosimetric advantage appears reductive. Indeed, the precise targeting of PT may help evaluate the effectiveness of de-escalation strategies, especially for patients with human papillomavirus associated-oropharyngeal cancer (OPC) and nasopharyngeal cancer (NPC). Furthermore, PT could have potentially greater immunogenic effects than conventional photon therapy, possibly enhancing both the radiotherapy (RT) capability to activate anti-tumor immune response and the effectiveness of immunotherapy drugs. Based on these premises, the aim of the present paper is to conduct a narrative review reporting the safety and efficacy of PT compared to photon RT focusing on NPC and OPC. We also provide a snapshot of ongoing clinical trials comparing PT with photon RT for these two clinical scenarios. Finally, we discuss new insights that may further develop clinical research on PT for HNC.
Objective: Accurate patient positioning is crucial in particle therapy due to the geometrical selectivity of particles. We report and discuss the National Center for Oncological Hadrontherapy (CNAO) experience in positioning accuracy and stability achieved with solid thermoplastic masks fixed on index base plates and assessed by daily orthogonal X-ray imaging. Methods: Positioning data were retrospectively collected (between 2012 and 2018) and grouped according to the treated anatomical site. 19696 fractions of 1325 patients were evaluated. The study was designed to assess: (i) the number of fractions in which a single correction vector was applied(SCV); (ii) the number of fractions in which further setup verification was performed (SV); (iii) the number of fractions in which SV lead to an additional correction within (MCV5min) 5 minutes from the first setup correction; (iv) the systematic (Σ) and random (σ) error components of the correction vectors applied. Results: A SCV was applied in 71.5% of fractions, otherwise SV was required. In 30.6% of fractions with SV, patient position was not further revised. In the remaining fractions, MCV5min were applied mainly in extracranial and cranial sites respectively. Interfraction Σ was ≤ 1.7 mm/0.7° and σ was ≤ 1.2 mm/0.6° in cranial sites while in extracranial sites Σ was ≤ 5.5 mm/0.9° and σ was ≤4.4 mm/0.9°. Setup residuals were submillimetric in all sites. In cranial patients, maximum intrafractional Σ was 0.8 mm/0.4°. Conclusion: This report extensively quantifies inter- and intrafraction setup accuracy on an institutional basis and confirms the need of image guidance to fully benefit from the geometrical selectivity of particles. Advances in knowledge: The reported analysis provides a board institutional data set on the evaluation of patient immobilization and bony anatomy alignment for several particle therapy clinical indications.