The Fecal Immunoassay Occult Blood Test Combined With Calprotectin Sequential Linkage Imaging Endoscopy Screening Strategy for Monitoring Tumor Changes Associated With Long-duration Ulcerative Colitis

N/ANot Yet RecruitingNCT07742410

Qilu Hospital of Shandong University250 enrolled

Overview

Ulcerative colitis (UC) is a chronic inflammatory bowel disease associated with an increased risk of colorectal cancer, known as UC-associated neoplasia (UCAN). Current guidelines recommend regular colonoscopy surveillance for long-standing UC patients, but this strategy faces challenges including poor adherence and low neoplasia detection rates. This study aims to evaluate the diagnostic performance of a non-invasive pre-screening strategy combining fecal immunochemical test (FIT) and fecal calprotectin (FC), followed by linked color imaging (LCI) colonoscopy, for detecting UCAN in patients with long-standing UC. This is a multicenter, prospective, diagnostic cohort study. Eligible patients with long-standing UC (disease duration \>8 years for extensive colitis or \>10 years for left-sided colitis, or with PSC) will undergo FIT and FC testing, followed by LCI colonoscopy within 4 weeks regardless of stool test results. The primary outcome is the diagnostic performance (sensitivity, specificity, PPV, NPV) of combined FIT+FC testing for UCAN, using LCI colonoscopy with histopathology as the reference standard. A total of 250 participants will be enrolled from 6 centers in China. Secondary outcomes include UCAN detection rate, feasibility indicators, patient adherence and acceptability, optimal cut-off values for FIT and FC, and 12-month miss rate.

Study Type

OBSERVATIONAL

Enrollment

250

Conditions

Ulcerative Colitis (UC)

Eligibility

Sex: ALLMin age: 18 YearsMax age: 75 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Age 18-75 years, any gender. * Definite diagnosis of ulcerative colitis by clinical, endoscopic, and pathological criteria. * Meeting at least one of the following high-risk criteria (with first onset of mucopurulent bloody stool as the starting time): E1/E2 disease duration \>10 years; E3 disease duration \>8 years; with primary sclerosing cholangitis (PSC); first-degree family history of colorectal cancer; history of colorectal neoplasia resected. * Discontinued any form of glucocorticoids for at least 4 weeks prior to enrollment. * In clinical remission at enrollment (stool frequency score \<3, rectal bleeding score = 0). * Able to understand the study, voluntarily participate, and sign written informed consent. Exclusion Criteria: * Presence of other gastrointestinal diseases or tumors. * Severe comorbidities (e.g., cardiopulmonary insufficiency, hepatic or renal failure) that may affect study results or preclude tolerance of endoscopy. * Currently taking antiplatelet or anticoagulant medications (aspirin, warfarin, rivaroxaban, etc.). * Pregnant or breastfeeding women. * History of total or subtotal colectomy.

Outcomes

Primary Outcomes

Diagnostic Performance of Combined FIT+FC for UCAN

Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (LR+), and negative likelihood ratio (LR-) of combined FIT+FC testing (either positive defined as positive) for detecting UCAN, using LCI colonoscopy with histopathology as the reference standard.

Time frame: At time of colonoscopy (within 4 weeks after stool sample collection)

Secondary Outcomes

UCAN Detection Rate

Proportion of patients with pathologically confirmed UCAN (LGD, HGD, or CRC) among all patients who complete LCI colonoscopy

Time frame: At time of colonoscopy

Comprehensive completion rate of the joint screening process

Unit of measurement: Percentage (%) Detailed description To evaluate the overall implementation quality of the "FIT+FC sequential LCI" screening strategy, this indicator was set as a composite endpoint. Summary rule (mathematical definition) : Subjects who simultaneously meet all of the following five conditions are defined as "fully compliant process participants" : * Fecal sample collection was successful; * The sample quality is qualified; * Both the FIT and FC laboratory tests have been completed. ④ Complete the LCI colonoscopy within 4 weeks; ⑤ The Boston Quality of Bowel Preparation Scale (BBPS) score is ≥ 6 points. The reported value of this result measurement item = (the number of fully compliant process participants/the total number of participants in the group) × 100%. (Note: The completion rates of each individual link will be presented as baseline characteristics or descriptive data in the attached materials, and will not be separately used as result measurement items for

Time frame: Week 4 LCI colonoscopy

Patient Adherence

Proportion of patients completing colonoscopy within the 4-week time window

Time frame: Within 4 weeks after stool collection

Patient Acceptability

Patient acceptance scores for stool testing and colonoscopy, discomfort scores, willingness to repeat, assessed by standardized questionnaire. 1. Fecal Test Acceptability Questionnaire, score range: 6 to 30 points. The meaning of the score: A higher score = better results (higher acceptance). 2. Colonoscopy Experience Scale Score range: • Acceptance dimension (Items 1-3) : 3-15 points * Comfort/Discomfort dimension (Items 4-6) : 3-15 points (Note direction) Overall experience dimension (Items 7-9) : 3-15 points * Total score: 9-45 points Score meaning: A higher score = a better outcome (higher acceptance, less discomfort, and a better overall experience) 3. Willingness for Repeat Examination Score range: 4 to 20 points Score meaning: A higher score = a better outcome (stronger willingness to accept again)

Time frame: At 4-week follow-up

Optimal Cut-off Values

Optimal cut-off values for FIT and FC alone and in combination for predicting UCAN, determined by ROC curve analysis

Time frame: Week 52

12-Month Miss Rate

Proportion of new UCAN cases detected during 12-month follow-up among patients with negative baseline colonoscopy

Time frame: 12 months after baseline