UMIN-ICDS Clinical Trial

Public title

Study of Muscle Condition on Preoperative CT and the Risk of Pneumonia After Gastric Cancer Surgery

Acronym

CT-derived Muscle Phenotype and Pneumonia

Scientific Title

Association of Preoperative CT-Derived Skeletal Muscle Quantity and Quality With Postoperative Pneumonia After Gastrectomy for Gastric Cancer: A Retrospective Cohort Study

Scientific Title:Acronym

CT-MQP-GC Study

Region

Japan

Condition

Gastric Cancer

Classification by specialty

Gastrointestinal surgery

Classification by malignancy

Malignancy

Genomic information

NO

Narrative objectives1

The primary objective of this study is to evaluate the association between preoperative CT-derived skeletal muscle quantity and quality and the development of postoperative pneumonia in patients undergoing curative gastrectomy for gastric cancer. Muscle quantity will be assessed using the psoas muscle index (PMI), and muscle quality using psoas muscle CT attenuation, to determine whether patients with concomitant impairment in both measures have an increased risk of postoperative pneumonia.

Basic objectives2

Efficacy

Basic objectives -Others

Trial characteristics_1

Confirmatory

Trial characteristics_2

Explanatory

Developmental phase

Not applicable

Primary outcomes

The primary outcome is postoperative pneumonia occurring during the postoperative hospital stay after gastrectomy. Postoperative pneumonia is defined by the presence of fever and a new pulmonary infiltrate on chest radiography, with supportive clinical findings such as increased or purulent sputum and impaired oxygenation.

Key secondary outcomes

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

Not applicable

Age-upper limit

Not applicable

Gender

Male and Female

Key inclusion criteria

Patients who underwent gastrectomy with curative intent for primary gastric adenocarcinoma at our institution between January 2010 and December 2025.
Patients who achieved R0 resection.
Patients with evaluable preoperative CT images obtained within 30 days before surgery.
Patients with available clinicopathological data required for the study analyses.

Key exclusion criteria

Patients who underwent R1 or R2 resection.
Patients with distant metastasis at the time of surgery.
Patients without available preoperative CT images or with incomplete clinicopathological data required for the study analyses.

Target sample size

1098

Name of lead principal investigator

1st name	Hironori
Middle name
Last name	Tsujimoto

Organization

National Defense Medical College

Division name

Department of Surgery

Zip code

3598513

Address

3-2 Namiki, Tokorozawa

TEL

0429951637

Email

tsujihi@ndmc.ac.jp

Name of contact person

1st name	Hironori
Middle name
Last name	Tsujimoto

Organization

National Defense Medical College

Division name

Department of Surgery

Zip code

3598513

Address

3-2 Namiki, Tokorozawa

TEL

0429951637

Homepage URL

Email

tsujihi@ndmc.ac.jp

Institute

National Defense Medical College

Institute

Department

Personal name

Hironori Tsujimoto

Organization

JSPS KAKENHI

Organization

Division

Category of Funding Organization

Japanese Governmental office

Nationality of Funding Organization

Co-sponsor

Name of secondary funder(s)

Organization

National Defense Medical College

Address

3-2 Namiki, Tokorozawa

Tel

0429951637

Email

tsujihi@ndmc.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

防衛医科大学校病院

Date of disclosure of the study information

2026

Year

08

Month

20

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

Enrolling by invitation

Date of protocol fixation

2026

Year

07

Month

10

Day

Date of IRB

2026

Year

07

Month

16

Day

Anticipated trial start date

2026

Year

07

Month

17

Day

Last follow-up date

2027

Year

12

Month

31

Day

Date of closure to data entry

Date trial data considered complete

Date analysis concluded

Other related information

This is a single-center retrospective cohort study of patients who underwent gastrectomy with curative intent for primary gastric adenocarcinoma at our institution between January 2010 and December 2025. Consecutive eligible patients during the study period will be included. Skeletal muscle quantity will be assessed using the psoas muscle index (PMI), and muscle quality using psoas muscle CT attenuation on preoperative CT images obtained within 30 days before surgery. The main exposures are sex-standardized PMI and CT attenuation and a combined muscle quantity-quality phenotype derived from these measures. The primary outcome is postoperative pneumonia occurring during the postoperative hospital stay. The association between preoperative CT-derived muscle quantity and quality and postoperative pneumonia will be evaluated. No study-specific intervention will be performed, and existing clinical and imaging data will be analyzed.

Registered date

2026

Year

08

Month

14

Day

Last modified on

2026

Year

08

Month

14

Day

Link to view the page

Value
https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000071629