Dataset for predicting single-spot proton ranges in proton therapy of prostate cancer

AbstractThe number of radiotherapy patients treated with protons has increased from less than 60,000 in 2007 to more than 220,000 in 2019. However, the considerable uncertainty in the positioning of the Bragg peak deeper in the patient raised new challenges in the proton therapy of prostate cancer (PCPT). Here, we describe and share a dataset where 43 single-spot anterior beams with defined proton energies were delivered to a prostate phantom with an inserted endorectal balloon (ERB) filled either with water only or with a silicon-water mixture. The nuclear reactions between the protons and the silicon yield a distinct prompt gamma energy line of 1.78 MeV. Such energy peak could be identified by means of prompt gamma spectroscopy (PGS) for the protons hitting the ERB with a three-sigma threshold. The application of a background-suppression technique showed an increased rejection capability for protons hitting the prostate and the ERB with water only. We describe each dataset, document the full processing chain, and provide the scripts for the statistical analysis.

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Towards real-time PGS range monitoring in proton therapy of prostate cancer

Scientific Reports ◽

10.1038/s41598-021-93612-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Paulo Magalhaes Martins ◽

Hugo Freitas ◽

Thomas Tessonnier ◽

Benjamin Ackermann ◽

Stephan Brons ◽

...

Keyword(s):

Prostate Cancer ◽

Radiation Exposure ◽

Real Time ◽

Proton Therapy ◽

Gamma Spectroscopy ◽

Organs At Risk ◽

Intensity Modulated Radiation Therapy ◽

Anatomical Variations ◽

Prompt Gamma ◽

Binary Approach

AbstractProton therapy of prostate cancer (PCPT) was linked with increased levels of gastrointestinal toxicity in its early use compared to intensity-modulated radiation therapy (IMRT). The higher radiation dose to the rectum by proton beams is mainly due to anatomical variations. Here, we demonstrate an approach to monitor rectal radiation exposure in PCPT based on prompt gamma spectroscopy (PGS). Endorectal balloons (ERBs) are used to stabilize prostate movement during radiotherapy. These ERBs are usually filled with water. However, other water solutions containing elements with higher atomic numbers, such as silicon, may enable the use of PGS to monitor the radiation exposure of the rectum. Protons hitting silicon atoms emit prompt gamma rays with a specific energy of 1.78 MeV, which can be used to monitor whether the ERB is being hit. In a binary approach, we search the silicon energy peaks for every irradiated prostate region. We demonstrate this technique for both single-spot irradiation and real treatment plans. Real-time feedback based on the ERB being hit column-wise is feasible and would allow clinicians to decide whether to adapt or continue treatment. This technique may be extended to other cancer types and organs at risk, such as the oesophagus.

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Multiple Gamma-Ray Detection Capability of a CeBr3 Detector for Gamma Spectroscopy

Journal of Spectroscopy ◽

10.1155/2017/5634384 ◽

2017 ◽

Vol 2017 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

A. A. Naqvi ◽

F. Z. Khiari ◽

F. A. Liadi ◽

Khateeb ur-Rehman ◽

M. Raashid ◽

...

Keyword(s):

Energy Range ◽

Gamma Rays ◽

Gamma Ray ◽

Gamma Spectroscopy ◽

Prompt Gamma ◽

Detection Capability ◽

Gamma Energy ◽

Best Value ◽

Detection Capabilities ◽

Good Agreement

The newly developed cerium tribromide (CeBr3) detector has reduced intrinsic gamma-ray activity with gamma energy restricted to 1400–2200 keV energy range. This narrower region of background gamma rays allows the CeBr3 detector to detect more than one gamma ray to analyze the gamma-ray spectrum. Use of multiple gamma-ray intensities in elemental analysis instead of a single one improves the accuracy of the estimated results. Multigamma-ray detection capability of a cylindrical 75 mm × 75 mm (diameter × height) CeBr3 detector has been tested by analyzing the chlorine concentration in water samples using eight chlorine prompt gamma rays over 517 to 8578 keV energies utilizing a D-D portable neutron generator-based PGNAA setup and measuring the corresponding minimum detection limit (MDC) of chlorine. The measured MDC of chlorine for gamma rays with 517–8578 keV energies varies from 0.07 ± 0.02 wt% to 0.80 ± 0.24. The best value of MDC was measured to be 0.07 ± 0.02 wt% for 788 keV gamma rays. The experimental results are in good agreement with Monte Carlo calculations. The study has shown excellent detection capabilities of the CeBr3 detector for eight prompt gamma rays over 517–8578 keV energy range without significant background interference.

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Preliminary analysis of prostate positional displacement using hydrogel spacer during the course of proton therapy for prostate cancer

Journal of Radiation Research ◽

10.1093/jrr/rraa115 ◽

2020 ◽

Author(s):

Hiroki Sato ◽

Takahiro Kato ◽

Tomoaki Motoyanagi ◽

Kimihiro Takemasa ◽

Yuki Narita ◽

...

Keyword(s):

Prostate Cancer ◽

Proton Therapy ◽

Rectal Dose ◽

Prostate Motion ◽

Significant Difference ◽

Risk Prostate Cancer ◽

Bony Anatomy ◽

Study Population ◽

Planning Ct ◽

Anterior Posterior

Abstract In recent years, a novel technique has been employed to maintain a distance between the prostate and the rectum by transperineally injecting a hydrogel spacer (HS). However, the effect of HS on the prostate positional displacement is poorly understood, despite its stability with HS in place. In this study, we investigated the effect of HS insertion on the interfraction prostate motion during the course of proton therapy (PT) for Japanese prostate cancer patients. The study population consisted of 22 cases of intermediate-risk prostate cancer with 11 cases with HS insertion and 11 cases without HS insertion. The irradiation position and preparation were similar for both groups. To test for reproducibility, regular confirmation computed tomography (RCCT) was done four times during the treatment period, and five times overall [including treatment planning CT (TPCT)] in each patient. Considering the prostate position of the TPCT as the reference, the change in the center of gravity of the prostate relative to the bony anatomy in the RCCTs of each patient was determined in the left–right (LR), superior–inferior (SI) and anterior–posterior (AP) directions. As a result, no significant difference was observed across the groups in the LR and SI directions. Conversely, a significant difference was observed in the AP direction (P < 0.05). The proportion of the 3D vector length ≤5 mm was 95% in the inserted group, but 55% in the non-inserted group. Therefore, HS is not only effective in reducing rectal dose, but may also contribute to the positional reproducibility of the prostate.

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