To investigate the efficacy of mechanical thrombectomy (MT) for large vessel occlusion (LVO) in patients with Trousseau's syndrome (TS). 

TS is a hypercoagulability state defined by unexplained thrombotic events that precede the diagnosis of an occult malignancy or appear concomitantly with the tumor. A patient with TS may develop acute ischemic stroke due to LVO before cancer diagnosis but the efficacy of MT remains unclear in TS. 

Of 1,498 patients admitted to our center with acute ischemic stroke between April 2019 and July 2025, 39 (2.6%) were diagnosed with TS. We retrospectively reviewed their clinical features, treatment, and outcome.

Median age at symptom onset was 73 years (IQR 58–81 years). 22 (56%) were male. Median premorbid mRS score was 1 (IQR 0–3). All had cancers (n=34 [87%] stage IV); lung was the most common site (n=9, 23%), followed by pancreas (n=6), uterus (n=5), ovary (n=4), stomach (n=4), gallbladder (n=4), and others (n=7). 11 (28%) didn't have a cancer diagnosis at presentation. 3 (7.7%) had atrial fibrillation. All patients showed high D-dimer levels (median 12.94 µg/mL, IQR 8.69-24.99 µg/mL). 14 (36%) received anticoagulation therapy (DOAC, n=13, heparin, n=1) before presentation while 6 (15%) anti-platelet drug. 16 (41%) had LVO; 14/16 (88%) underwent MT, 12/14 (86%) achieved successful recanalization (TICI >2b), and 3/12 (25%) became able to walk independently (mRS 0-3). 36 (92%) received heparin after admission. 1/14 (7.1%) treated with MT developed symptomatic intracranial hemorrhage. Functional outcome at 3 months was not different between those with and without recanalization (mRS median 5 [0–6] vs. 6 [6–6]), but only 3/14 (21%), who achieved good outcome (mRS 0 [n=2], 3 [n=1]), became able to receive chemotherapy. 

MT may not alter the patients' long-term outcome, but it may increase a chance to live independently for the rest of their lives and to get chemotherapy.