Utility of a scoring system for differentiating cancer-associated stroke from cryptogenic stroke in patients with cancer.

Background: The commonest type of ischemic cerebral stroke in patients with cancer is cryptogenic stroke (CRS), the majority of which are considered cancer-associated strokes (CAS) caused by multiple microemboli associated with hypercoagulation, known as Trousseau syndrome. However, detection of microemboli and diagnosing CAS is difficult. We have therefore developed a scoring system for diagnosing CAS.

Methods: We retrospectively examined data of patients with cancer and stroke between 2006 and 2017. We identified risk factors for CRS, assigned them one or two points, and calculated total scores (Trousseau score) for each patient. We used overall survival after stroke (OSs) to validate the utility of the system.

Results: In 181 consecutive strokes, CRS was the commonest type (43.6%) and had a short OSs (median 56 days). We identified the following five risks for CRS: high D-dimer concentration (≥ 10.0 μg/mL) and lesions in multiple territories (two points each); and active cancer, low platelet count (150,000/μL>) and female sex (one point each). Trousseau score ≥ 3 indicated CAS (50.3%), which had a median OSs of 50 days. Only CAS (hazard ratio 3.44 [2.34-5.10], P < 0.0001) and poor performance status (3 or 4) (2.27 [1.50-3.39], P = 0.0002) were risk factors for OSs; CRS was not. OSs of patients with non-CAS/CRS was significantly longer than that of those with CAS/CRS (404.5 days vs. 47 days, P = 0.0114), whereas OSs of CAS/non-CRS was much shorter than that of non-CAS/non-CRS (53 days vs. 547 days, P < 0.0001).

Conclusion: Trousseau scores simply and clearly identify CAS.