臨床研究等提出・公開システム

Date of registration	June. 25, 2026
Last modified on	June. 25, 2026
Trial ID	jRCT1040260073

Scientific Title	Cholesteatoma Registry for Surgical Strategy - Japan (CROSS-J)
Public Title	Nationwide registry study of surgery for middle ear cholesteatoma (CROSS-J)

Contact for Scientific Queries	Name	Morita Yuka
	Affiliation	University of Toyama
	Address	2630 Sugitani, Toyama, Toyama 930-0152, Japan
	Telephone	+81-76-434-2315
	E-mail	yukam@med.u-toyama.ac.jp
Contact for Public Queries	Name	Morita Yuka
	Affiliation	University of Toyama
	Address	2630 Sugitani, Toyama, Toyama 930-0152, Japan
	Telephone	+81-76-434-2315
	E-mail	yukam@med.u-toyama.ac.jp

Recruitment status	Pending

Anticipated date of first enrollment		June. 25, 2026
Target sample size		8000
Study Type		Observational
Study Design	allocation	non-randomized controlled trial
	masking	open(masking not used)
	control	uncontrolled control
	assignment	factorial assignment
	purpose	treatment purpose
Key inclusion & exclusion criteria	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.
	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.
	Age Minimum	No limit
	Age Maximum	No limit
	Gender	Both
Health Condition(s) or Problem(s) Studied		Middle ear cholesteatoma
Health Condition(s) Keyword		Middle ear cholesteatoma, cholesteatoma,
Health Condition(s) Code		D018424
Primary Outcome(s)		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.
Secondary Outcome(s)		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.

Primary Sponsor	none

Source of Monetary Support	Japan Otological Society
Secondary Sponsor	Not applicable

Name of Certified Review Board	University of Toyama Clinical Research Review Board
Address	2630 Sugitani, Toyama, Toyama 930-0152, Japan, Toyama
Telephone	+81-76-415-8857
E-Mail	kenrinri@adm.u-toyama.ac.jp
Approval Status	Approval
Date of approval	Mar. 31, 2026

Plan to share IPD	No

Secondary ID(s)	UMIN000062052
Issuing Authority	UMIN Clinical Trials Registry

Countries of Recruitment（Except Japan）	none