Evidence map›Paper›PMID 41952792›Full record

ArticleInternational journal of particle therapy2026

Safe Proton Beam Re-irradiation With a Bioabsorbable Spacer in Pancreatic Cancer: A Case Report.

Shintaro Shiba, Koichi Tokuuye, Kazuya Koizumi, Toshiyasu Kawahara, Noriko Fujiwara, Hiroki Yamaue, Shoichi Fujii, Motoko Omura

Abstract readCase Reports
In one paragraph

Article in International journal of particle therapy, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0cells of the map it votes in
0citing papers in PubMed
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1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

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Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

8 authors.

Shintaro ShibaDepartment of Radiation Oncology, Shonan Kamakura General Hospital, 1370-1, Okamoto, Kamakura, Kanagawa 247-8533, Japan.
Koichi TokuuyeDepartment of Radiation Oncology, Shonan Kamakura General Hospital, 1370-1, Okamoto, Kamakura, Kanagawa 247-8533, Japan.
Kazuya KoizumiGastroenterology Medicine Center, Shonan Kamakura General Hospital, 1370-1, Okamoto, Kamakura, Kanagawa 247-8533, Japan.
Toshiyasu KawaharaPancreatic Cancer Center, Shonan Kamakura General Hospital, 1370-1, Okamoto, Kamakura, Kanagawa 247-8533, Japan.
Noriko FujiwaraPancreatic Cancer Center, Shonan Kamakura General Hospital, 1370-1, Okamoto, Kamakura, Kanagawa 247-8533, Japan.
Hiroki YamauePancreatic Cancer Center, Shonan Kamakura General Hospital, 1370-1, Okamoto, Kamakura, Kanagawa 247-8533, Japan.
Shoichi FujiiDepartment of Surgery, Shonan Kamakura General Hospital, 1370-1, Okamoto, Kamakura, Kanagawa 247-8533, Japan.
Motoko OmuraDepartment of Radiation Oncology, Shonan Kamakura General Hospital, 1370-1, Okamoto, Kamakura, Kanagawa 247-8533, Japan.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Purpose: Proton beam therapy (PBT) re-irradiation for pancreatic cancer is challenging because of accumulated dose limits in surrounding gastrointestinal organs. Bioabsorbable polyglycolic acid (PGA) spacers can reduce radiation exposure to adjacent organs. This report aims to detail the safe execution of PBT re-irradiation for recurrent pancreatic body cancer adjacent to the stomach using a PGA spacer and physically verify the spacer's proton beam blocking effectiveness via auto-activation positron emission tomography (AAPET). Patients and Methods: A 77-year-old female with pancreatic body cancer experienced local residual disease 6 months after an initial PBT course (67.5 Gy (RBE)/25 fractions). To enable a second PBT, a 1-cm-thick PGA spacer was successfully placed between the stomach and the pancreas. The second PBT delivered 67.5 Gy (RBE) in 25 fractions using 2 posterior beams to avoid gastric passage. AAPET-CT was performed 3 times during the second PBT. Quantitative analysis compared the average Becquerel (Bq)/ml values in the planning target volume, the stomach (ventral to the spacer), and abdominal regions outside the field. Results: Maximum doses to the stomach and duodenum were limited to 16.1 Gy (RBE) and 16.7 Gy (RBE), respectively. Quantitative AAPET analysis showed the average Bq/ml value in the planning target volume was significantly higher than in other regions. This visually and quantitatively confirmed the spacer's effectiveness in stopping the proton beams. Three months after the second PBT, the irradiated site was controlled, and no adverse events related to PBT or PGA spacers were observed. Conclusion: In a case of recurrent pancreatic body cancer adjacent to the stomach, safe proton beam re-irradiation was successfully performed by placing a PGA spacer. PGA spacer placement may represent an effective strategy for safely achieving PBT re-irradiation for recurrent pancreatic cancer near the gastrointestinal tract.

Indexed as

Auto-activation PETPancreatic cancerProton beam therapyRe-irradiationSpacer

Identifiers

PMID41952792
PMCPMC13054066

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.