UMIN-ICDS Clinical Trial

Public title

A Prospective Observational Study on the Feasibility of Radiotherapy Treatment Planning Using Photon-Counting CT

Acronym

A Prospective Observational Study on the Feasibility of Radiotherapy Treatment Planning Using Photon-Counting CT

Scientific Title

A Prospective Observational Study on the Feasibility of Radiotherapy Treatment Planning Using Photon-Counting CT

Scientific Title:Acronym

A Prospective Observational Study on the Feasibility of Radiotherapy Treatment Planning Using Photon-Counting CT

Region

Japan

Condition

Malignant neoplasms

Classification by specialty

Radiology

Classification by malignancy

Malignancy

Genomic information

NO

Narrative objectives1

Photon-counting CT (PCCT) offers high spatial resolution, low image noise, and spectral information, which may improve the accuracy of target and organ-at-risk delineation and dose calculation in radiotherapy planning.

This single-arm, prospective observational basket study includes patients eligible for definitive radiotherapy, intensity-modulated radiation therapy (IMRT), or stereotactic radiotherapy (SBRT/SRT/SRS) across multiple anatomical sites. The study aims to assess the feasibility of completing treatment plans of clinically acceptable quality using only PCCT simulation images and to evaluate the imaging and treatment planning characteristics of PCCT.

Basic objectives2

Efficacy

Basic objectives -Others

Trial characteristics_1

Trial characteristics_2

Developmental phase

Primary outcomes

Proportion of patients for whom radiotherapy planning was completed using PCCT images alone and the resulting plan was used clinically.

Key secondary outcomes

Imaging assessments: Evaluation and comparison of image quality among PCCT images, historical control images, and phantom images, including image noise, contrast-to-noise ratio (CNR), signal-to-noise ratio (SNR), lesion contrast (LC), spatial resolution, metal artifact scores, and visual assessments; and assessment of the ability to identify tumors and normal tissues on PCCT images compared with previous diagnostic images (CT, MRI, and FDG-PET/CT) in the same patient.
Radiotherapy assessments: Workflow metrics (CT simulation time); spectral features used during PCCT imaging, including virtual monochromatic images (VMI), material discrimination, effective atomic number, and Rho/Z; accuracy of electron density conversion and its impact on dose calculation; accuracy of target and organ-at-risk (OAR) delineation and delineated volumes; accuracy of treatment planning and dose distributions; treatment plan quality assurance (QA), including gamma passing rates, dose verification results, and imaging radiation dose; and assessment of treatment delivery, including image-guided setup verification using IGRT/CBCT or other modalities, setup errors, and reproducibility of treatment delivery.
Clinical outcomes: Exploratory evaluation of the cumulative incidence of local recurrence, recurrence-free survival, overall survival, patterns of recurrence, treatment completion rate, incidence of adverse events, incidence of grade 3 or higher adverse events, objective response rate according to RECIST version 1.1, and complete response rates (clinical complete response [cCR] and pathological complete response [pCR]). For patients receiving perioperative treatment, R0 resection rate, downstaging rate, and histopathological response will also be evaluated. Comparisons with historical cases will be performed.

Study type

Observational

Basic design

Randomization

Randomization unit

Blinding

Control

Stratification

Dynamic allocation

Institution consideration

Blocking

Concealment

No. of arms

Purpose of intervention

Type of intervention

Interventions/Control_1

Interventions/Control_2

Interventions/Control_3

Interventions/Control_4

Interventions/Control_5

Interventions/Control_6

Interventions/Control_7

Interventions/Control_8

Interventions/Control_9

Interventions/Control_10

Age-lower limit

18

years-old

<=

Age-upper limit

Not applicable

Gender

Male and Female

Key inclusion criteria

Patients must meet all of the following criteria:
1) A clinical decision has been made to administer definitive radiotherapy, intensity-modulated radiation therapy (IMRT), or stereotactic radiotherapy (SBRT, SRT, or SRS).
2) CT simulation (CT-S) is required for radiotherapy planning.
3) The planned treatment site is one of the following: intracranial (brain), head and neck, thorax, abdomen (liver, biliary tract, or pancreas), pelvis, or bone/spine. Both metastatic and primary brain tumors are eligible.
4) Age 18 years or older at enrollment.
5) Eastern Cooperative Oncology Group performance status (ECOG PS) of 0 to 2.
6) Written informed consent to participate in the study has been obtained from the patient.

Key exclusion criteria

Patients meeting any of the following criteria will be excluded:
1) Pregnant, breastfeeding, or potentially pregnant.
2) Unable to safely undergo CT simulation using PCCT because of difficulty maintaining the required position.
3) Radiotherapy is intended solely for palliation.

Target sample size

160

Name of lead principal investigator

1st name	Hiroshi
Middle name
Last name	Doi

Organization

Wakayama medical university

Division name

Department of Radiology

Zip code

641-8509

Address

811-1 Kimiidera, Wakayama, Wakayama, Japan

TEL

0734410605

Email

hirosidoi@wakayama-med.ac.jp

Name of contact person

1st name	Takaya
Middle name
Last name	Inagaki

Organization

Wakayama medical university

Division name

Department of Radiology

Zip code

641-8509

Address

811-1 Kimiidera, Wakayama, Wakayama, Japan

TEL

0734410605

Homepage URL

Email

inagaki@wakayama-med.ac.jp

Institute

Wakayama medical university

Institute

Department

Personal name

Takaya Inagaki

Organization

Dpartment of Radiology, Wakayama Medical University

Organization

Division

Category of Funding Organization

Self funding

Nationality of Funding Organization

Japan

Co-sponsor

Name of secondary funder(s)

Organization

Research Ethics Committee of Wakayama Medical University

Address

811-1 Kimiidera, Wakayama, Wakayama, Japan

Tel

073-447-2300

Email

wa-rinri@wakayama-med.ac.jp

Secondary IDs

NO

Study ID_1

Org. issuing International ID_1

Study ID_2

Org. issuing International ID_2

IND to MHLW

Institutions

Date of disclosure of the study information

2026

Year

11

Month

04

Day

URL releasing protocol

Publication of results

Unpublished

URL related to results and publications

Number of participants that the trial has enrolled

Results

Results date posted

Results Delayed

Results Delay Reason

Date of the first journal publication of results

Baseline Characteristics

Participant flow

Adverse events

Outcome measures

Plan to share IPD

IPD sharing Plan description

Recruitment status

Preinitiation

Date of protocol fixation

2026

Year

10

Month

06

Day

Date of IRB

2026

Year

11

Month

02

Day

Anticipated trial start date

2026

Year

11

Month

09

Day

Last follow-up date

2029

Year

12

Month

31

Day

Date of closure to data entry

Date trial data considered complete

Date analysis concluded

Other related information

none

Registered date

2026

Year

11

Month

04

Day

Last modified on

2026

Year

11

Month

04

Day

Link to view the page

Value
https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000072687