Intensive Cancer Screening After Cryptogenic Stroke (INCOGNITO)

Intensive Cancer Screening After Cryptogenic Stroke (INCOGNITO) Pilot Randomized Trial

The INCOGNITO Pilot Trial is a single centre pilot prospective randomized open-label blinded endpoint (PROBE) trial to assess the feasibility of a full-scale randomized trial to determine whether an occult cancer screening strategy of FDG PET/CT (F-fluorodeoxyglucose positron emission/computed tomography) in addition to usual care increases the number of occult cancers diagnosed after screening compared to usual care cancer screening alone in patients with cryptogenic stroke.

Study Overview

• Status: Recruiting
• Conditions: Occult Cancer
• Intervention / Treatment: Diagnostic test: FDG PET/CT; Diagnostic test: Usual Care

• Study Type: Interventional
• Enrollment (Estimated): 45
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Dariush Dowlatshahi, MD PhD; Phone Number: 14709 613-798-5555; Email: ddowlat@toh.ca
• Study Contact Backup: Name: Deborah Siegal, MD; Phone Number: 78060 613-737-8899; Email: dsiegal@toh.ca

Study Locations

• Canada
  • Ontario
    • Ottawa, Ontario, Canada, K1Y 4E9
      • Recruiting
      • The Ottawa Hospital
      • Principal Investigator: Deborah Siegal, MD
      • Contact: Michele Demetroff; Phone Number: 6137985555; Email: mdemetrof@ohri.ca
      • Principal Investigator: Dariush Dowlatshahi, MD PhD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• adults ≥18 years
• presenting to the Ottawa Hospital Stroke Prevention Clinic or the Ottawa Hospital Neurovascular Unit with a first cryptogenic ischemic stroke after advanced evaluation as per American Heart Association guidelines and Saver approach (maximum 3 months after stroke)
• patient or delegate willing and able to provide informed consent.

Exclusion Criteria:

• contraindications to FDG PET/CT (pregnancy or unable to lie still in bed for 20 minutes)
• active cancer or previous cancer diagnosis (other than basal or squamous cell carcinoma of the skin)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: Usual Care; Cancer screening according to sex, age and risk as per Canadian Task Force on Preventative Health Care)	Diagnostic test: Usual Care; Cancer screening according to sex, age and risk as per Canadian Task Force on Preventative Health Care
Experimental: Intensive Cancer Screening; Usual care plus FDG PET/CT	Diagnostic test: FDG PET/CT; F-fluorodeoxyglucose positron emission/computed tomography

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Participant Recruitment	Number of participants recruited	Over 12 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Adherence Rate	adherence to screening strategy	Over 24 months
Eligibility Rate	percentage of screened patients who are eligible	Over 12 months
Consent Rate	percentage of eligible patients who provide consent	Over 12 months
Retention Rate	percentage of participants retained at follow-up	Over 24 months
Study Completion Rate	percentage of participants who completed all study procedures	Over 24 months

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Screening time frame	time from diagnosis to screening	Over 24 months
Reasons for participation	Reasons for accepting/declining participation	Over 24 months
Usual care cancer screening strategies	Usual care cancer screening strategies ordered by treating physicians	Over 24 months

Collaborators and Investigators

• Sponsor: Ottawa Hospital Research Institute
• Collaborators: Heart and Stroke Foundation of Canada; Brain Canada; Canadian Stroke Consortium (CSC)
• Investigators: Principal Investigator: Dariush Dowlatshahi, MD PhD, Ottawa Hospital Research Institute

Study record dates

Study Major Dates

• Study Start (Actual): September 1, 2023
• Primary Completion (Estimated): January 1, 2027
• Study Completion (Estimated): January 1, 2027

Study Registration Dates

• First Submitted: January 28, 2023
• First Submitted That Met QC Criteria: February 8, 2023
• First Posted (Actual): February 17, 2023

Study Record Updates

• Last Update Posted (Actual): July 31, 2025
• Last Update Submitted That Met QC Criteria: July 29, 2025
• Last Verified: July 1, 2025

More Information

Terms related to this study

• Keywords: cryptogenic stroke
• Additional Relevant MeSH Terms: Cerebrovascular Disorders; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Vascular Diseases; Cardiovascular Diseases; Stroke; Ischemic Stroke
• Other Study ID Numbers: 20230006-01H

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No