Homogeneity study of proton and carbon ion scanning beams using combinations of different spot sizes and grid sizes

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.

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Salvage robot-assisted radical prostatectomy after carbon ion radiotherapy: a case report

International Cancer Conference Journal ◽

10.1007/s13691-020-00464-w ◽

2021 ◽

Author(s):

Hiroki Kobayashi ◽

Satoshi Kobayashi ◽

Masaki Shiota ◽

Dai Takamatsu ◽

Tatsuro Abe ◽

...

Keyword(s):

Case Report ◽

Radical Prostatectomy ◽

Carbon Ion Radiotherapy ◽

Robot Assisted ◽

Carbon Ion

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Adaptive planning based on single beam optimization in passive scattering carbon ion radiotherapy for patients with pancreatic cancer

Radiation Oncology ◽

10.1186/s13014-021-01841-2 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Yang Li ◽

Yoshiki Kubota ◽

Masahiko Okamoto ◽

Shintaro Shiba ◽

Shohei Okazaki ◽

...

Keyword(s):

Pancreatic Cancer ◽

Carbon Ion Radiotherapy ◽

Adaptive Planning ◽

Carbon Ion ◽

Single Beam ◽

Original Plan ◽

Image Registration Algorithm ◽

Passive Scattering ◽

Accumulated Dose ◽

Dose Difference

Abstract Background Daily anatomical deviations may distort the dose distribution in carbon ion radiotherapy (CIRT), which may cause treatment failure. Therefore, this study aimed to perform re-planning to maintain the dose coverage in patients with pancreatic cancer with passive scattering CIRT. Methods Eight patients with pancreatic cancer and 95 daily computed tomography (CT) sets were examined. Two types of adaptive plans based on new range compensators (RCs) (AP-1) and initial RCs (AP-2) were generated. In AP-2, each beam was optimized by manually adjusting the range shifter thickness and spread-out Bragg peak size to make dose reduction by < 3% of the original plan. Doses of the original plan with bone matching (BM) and tumor matching (TM) were examined for comparison. We calculated the accumulated dose using the contour and intensity-based deformable image registration algorithm. The dosimetric differences in respect to the original plan were compared between methods. Results Using TM and BM, mean ± standard deviations of daily CTV V95 (%) difference from the original plan was − 5.1 ± 6.2 and − 8.8 ± 8.8, respectively, but 1.2 ± 3.4 in AP-1 and − 0.5 ± 2.1 in AP-2 (P < 0.001). AP-1 and AP-2 enabled to maintain a satisfactory accumulated dose in all patients. The dose difference was 1.2 ± 2.8, − 2,1 ± 1.7, − 7.1 ± 5.2, and − 16.5 ± 15.0 for AP-1, AP-2, TM, and BM, respectively. However, AP-2 caused a dose increase in the duodenum, especially in the left–right beam. Conclusions The possible dose deterioration should be considered when performing the BM, even TM. Re-planning based on single beam optimization in passive scattering CIRT seems an effective and safe method of ensuring the treatment robustness in pancreatic cancer. Further study is necessary to spare healthy tissues, especially the duodenum.

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Carbon ion radiotherapy for prostate cancer with bladder invasion

BMC Urology ◽

10.1186/s12894-021-00871-y ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Yuhei Miyasaka ◽

Hidemasa Kawamura ◽

Hiro Sato ◽

Nobuteru Kubo ◽

Tatsuji Mizukami ◽

...

Keyword(s):

Prostate Cancer ◽

Locally Advanced ◽

Therapeutic Benefit ◽

Carbon Ion Radiotherapy ◽

Safety And Efficacy ◽

Carbon Ion ◽

Grade 3 ◽

Bladder Invasion

Abstract Background The optimal management of clinical T4 (cT4) prostate cancer (PC) is still uncertain. At our institution, carbon ion radiotherapy (CIRT) for nonmetastatic PC, including tumors invading the bladder, has been performed since 2010. Since carbon ion beams provide a sharp dose distribution with minimal penumbra and have biological advantages over photon radiotherapy, CIRT may provide a therapeutic benefit for PC with bladder invasion. Hence, we evaluated CIRT for PC with bladder invasion in terms of the safety and efficacy. Methods Between March 2010 and December 2016, a total of 1337 patients with nonmetastatic PC received CIRT at a total dose of 57.6 Gy (RBE) in 16 fractions over 4 weeks. Among them, seven patients who had locally advanced PC with bladder invasion were identified. Long-term androgen-deprivation therapy (ADT) was also administered to these patients. Adverse events were graded according to the Common Terminology Criteria for Adverse Event version 5.0. Results At the completion of our study, all the patients with cT4 PC were alive with a median follow-up period of 78 months. Grade 2 acute urinary disorders were observed in only one patient. Regarding late toxicities, only one patient developed grade 2 hematuria and urinary urgency. There was no grade 3 or worse toxicity, and gastrointestinal toxicity was not observed. Six (85.7%) patients had no recurrence or metastasis. One patient had biochemical and local failures 42 and 45 months after CIRT, respectively. However, the recurrent disease has been well controlled by salvage ADT. Conclusions Seven patients with locally advanced PC invading the bladder treated with CIRT were evaluated. Our findings seem to suggest positive safety and efficacy profiles for CIRT.

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Carbon ion radiotherapy for recurrent calf myxoid liposarcoma: a case report

Journal of International Medical Research ◽

10.1177/03000605211009701 ◽

2021 ◽

Vol 49 (4) ◽

pp. 030006052110097

Author(s):

Xiaojun Li ◽

Yanshan Zhang ◽

Yancheng Ye ◽

Ying Qi ◽

Chunlan Feng ◽

...

Keyword(s):

Soft Tissue ◽

Soft Tissue Sarcomas ◽

Myxoid Liposarcoma ◽

Ion Beams ◽

Carbon Ion Radiotherapy ◽

Irradiation Damage ◽

Radiation Dermatitis ◽

Complete Disappearance ◽

Carbon Ion ◽

The Right

Liposarcoma (LPS) is the most common soft tissue sarcoma. Myxoid LPS (MLPS) is the second most common subtype of LPS and accounts for 25% to 50% of all LPSs. Like most other soft tissue sarcomas, the mainstay of treatment for LPS is inevitably surgery. Multidisciplinary approaches, including surgery, chemotherapy, and radiotherapy, have been successful in the treatment of LPS during the last three decades. Even so, recurrence of LPS remains challenging. Carbon ion beams produce increased energy deposition at the end of their range to form a Bragg peak while minimizing irradiation damage to surrounding tissues, which facilitates more precise dosage and localization than that achieved with photon beams. Furthermore, carbon ion beams have high relative biologic effectiveness. We herein describe a patient who developed recurrent MLPS in the right calf after two surgeries and underwent carbon ion radiotherapy (CIRT), achieving complete disappearance of the tumor. The patient developed Grade 1 radiation dermatitis 30 days after CIRT, but no other acute toxicities were observed. The tumor had completely disappeared by 120 days after CIRT, and the patient remained disease-free for 27 months after CIRT. The CARE guidelines were followed in the reporting of this case.

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