UMIN-CTR Clinical Trial

Public title

Cholesteatoma Registry for Surgical Strategy - Japan

Acronym

CROSS-J

Scientific Title

Cholesteatoma Registry for Surgical Strategy - Japan

Scientific Title:Acronym

CROSS-J

Region

Japan

Condition

Middle ear cholesteatoma

Classification by specialty

Oto-rhino-laryngology

Classification by malignancy

Others

Genomic information

NO

Narrative objectives1

The objective of this study is to establish a nationwide prospective registry of patients undergoing primary surgery for newly diagnosed middle ear cholesteatoma and to evaluate their long-term postoperative outcomes for up to 10 years. The study aims to clarify postoperative recurrence rates, hearing outcomes, changes in quality of life, and associations between disease classification, surgical procedures, and prognosis. The findings are expected to contribute to the establishment of optimal standard surgical strategies for middle ear cholesteatoma based on the JOS classification.

Basic objectives2

Others

Basic objectives -Others

An observational study to evaluate long-term outcomes, recurrence rates, hearing outcomes, quality of life, and associations between disease classification, surgical procedures, and prognosis in patients undergoing surgery for middle ear cholesteatoma.

Trial characteristics_1

Exploratory

Trial characteristics_2

Pragmatic

Developmental phase

Not applicable

Primary outcomes

The recurrence rate of middle ear cholesteatoma during the 10-year postoperative follow-up period. Recurrence will be assessed as the incidence of residual cholesteatoma and recurrent/retraction cholesteatoma.

Key secondary outcomes

Postoperative hearing improvement, assessed as the hearing success rate according to the JOS criteria.
Timing of recurrent/retraction cholesteatoma, analyzed during postoperative follow-up using the Kaplan-Meier method.
Proportion of patients requiring hearing rehabilitation on the affected or contralateral ear, including hearing aids, Baha, or cochlear implants.
Risk factors for recurrence according to disease classification, JOS classification, PTAM system, and surgical procedure.
Preoperative and postoperative changes in patient quality of life, assessed using COMOT-15 and COMQ-12.
Surgeon-reported quality of life and surgical workload, assessed using NASA-TLX.

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 newly diagnosed with middle ear cholesteatoma.
Patients whose cholesteatoma is classified as pars flaccida cholesteatoma, pars tensa cholesteatoma, secondary cholesteatoma, or congenital cholesteatoma.
Patients who undergo primary surgery for middle ear cholesteatoma during the study registration period.
Patients for whom written informed consent for participation in this study is obtained from the patient or a legally acceptable representative.
Patients treated at institutions certified as otologic surgery training facilities by the Japan Otological Society.
No restrictions are placed on age or sex.

Key exclusion criteria

Patients with a history of previous surgery for middle ear cholesteatoma.
Patients judged to be unable to undergo long-term postoperative follow-up for up to 10 years.
Patients whose disease status is unclear and cannot be classified into the predefined disease types.
Patients who do not provide consent for participation in this study or who withdraw consent.

Target sample size

8000

Name of lead principal investigator

1st name	Yuka
Middle name
Last name	Morita

Organization

University of Toyama

Division name

Department of Otolaryngology-Head and Neck Surgery

Zip code

930-0152

Address

2630 Sugitani, Toyama, Toyama 930-0152, Japan

TEL

076-434-2315

Email

yukam@med.u-toyama.ac.jp

Name of contact person

1st name	Yuka
Middle name
Last name	Morita

Organization

University of Toyama

Division name

Department of Otolaryngology-Head and Neck Surgery

Zip code

930-0152

Address

2630 Sugitani, Toyama, Toyama 930-0152, Japan

TEL

076-434-2315

Homepage URL

Email

yukam@med.u-toyama.ac.jp

Institute

University of Toyama

Institute

Department

Personal name

Organization

Japan Otological Society

Organization

Division

Category of Funding Organization

Other

Nationality of Funding Organization

Japan

Co-sponsor

St. Marianna University School of Medicine, Yamagata University, Kobe University, Keio University Hospital, Niigata University, Toho University Omori Medical Center, and other participating institutions listed in the study institution list

Name of secondary funder(s)

Organization

Clinical and Epidemiological Research Ethics Review Committee, University of Toyama

Address

2630 Sugitani, Toyama, Toyama, Japan

Tel

076-415-8857

Email

kenrinri@adm.u-toyama.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

富山大学附属病院（富山県）、聖マリアンナ医科大学病院（神奈川県）、山形大学医学部附属病院（山形県）、神戸大学医学部附属病院（兵庫県）、慶應義塾大学病院（東京都）、新潟大学医歯学総合病院（新潟県）、東邦大学医療センター大森病院（東京都）、その他研究協力機関等一覧に記載された全国の日本耳科学会耳科手術指導医制度認可研修施設

Date of disclosure of the study information

2026

Year

06

Month

25

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

03

Month

25

Day

Date of IRB

Anticipated trial start date

2026

Year

07

Month

01

Day

Last follow-up date

2039

Year

03

Month

31

Day

Date of closure to data entry

Date trial data considered complete

Date analysis concluded

Other related information

This is a multicenter prospective observational study of patients undergoing primary surgery for newly diagnosed middle ear cholesteatoma. No study-specific intervention, examination, treatment, or medication will be assigned. Surgical procedures, reconstruction materials, postoperative management, and the timing of hearing tests and imaging examinations will be determined solely by the attending physicians according to routine clinical practice. Patients who undergo primary surgery at participating institutions during the registration period will be registered in the EDC system and followed prospectively at 6 months, 1 year, 2 years, 3 years, 5 years, 8 years, and 10 years after surgery. Data on recurrence, hearing outcomes, imaging findings, tympanic membrane findings, patient-reported quality of life, and surgeon-reported workload/quality of life will be collected.

Registered date

2026

Year

06

Month

25

Day

Last modified on

2026

Year

06

Month

25

Day

Link to view the page

Value
https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000070999