Discovery of New Cancer in the 1-year Follow-up After Ischemic Stroke in Patients at Risk: The INVISIBLE-1 Study

Overview

INVISIBLE-1 aims to prospectively follow patients up to one year after ischemic stroke to: 1. Determine the cumulative incidence of occult cancer in patients with embolic stroke of undetermined source (ESUS) and elevated D-dimer 2. Describe occult cancer characteristics and spontaneous course of occult cancer Methodology The investigators will include 370 stroke patients with elevated D-dimer (≥ 820 μg/L) at the time of stroke, suspicion of ESUS after initial workup and without known cancer. The investigators will perform a follow-up telephone interview at one year to assess the occurrence of a new cancer and characterize the course of the disease. Significance Determining the real incidence of occult cancer in high-risk patients will help support the implementation of screening trials in the future. Faster detection and treatment of occult cancers would significantly impact patient' outcomes by offering faster cancer treatment and optimal secondary stroke prevention.

INVISIBLE-1 is the first prospective study conducting a 1-year post-stroke follow-up telephone interview in preselected stroke patients at high-risk for occult cancer. INVISIBLE-1 aims to: 1. Prospectively determine the cumulative incidence of occult cancer in patients with elevated D-dimer and ESUS within 1 year after the ischemic stroke 2. Describe occult cancer characteristics and spontaneous course of occult cancer Hypothesis Elevated D-dimer and suspicion of ESUS at admission may predict an underlying unknown cancer at the time of index stroke. The investigators hypothesize that the cumulative incidence of newly diagnosed cancer within 1 year after stroke reaches 15% in patients presenting these characteristics. This percentage is higher than the 10% currently known according to available retrospective studies. Project design To ensure the recruitment of the majority of potential occult cancer patients, the investigators set the D-dimer cut-off for inclusion of ≥ 820 μg/L at admission, based on our intern retrospective analyses of 1001 patients (OCCULT-5 score). In patients with ESUS, this cut-off was associated with a sensitivity of 91% and a specificity of 56% for the presence of an occult cancer diagnosed within 1 year after the index-stroke. As suggested by the current evidence, the investigators decided to set the limit for diagnosis of new cancer at 1 year after the index stroke. Beyond this period, the causality is questionable in our opinion.