Cerebral Microinfarcts Are Common in Undiagnosed Lung Cancer Patients: A Population-Based Study

Abstract

Background. Cerebral microinfarcts (CMI) represent covert brain ischemia and were associated with stroke risk and cognitive impairment. Magnetic resonance imaging diffusion-weighted imaging (DWI) hyperintensities have been suggested to represent acute CMI. The relationship between malignancy and CMI is unknown. Aims. We aimed to examine whether CMI is more common in patients with undiagnosed lung cancer, and therefore might serve as a prediction marker for cognitive impairment or cancer-related stroke. Methods. We used the computerized database of Clalit Health Services (the largest healthcare provider in Israel) to identify adults diagnosed with lung cancer who had an MRI brain scan for any indication prior to cancer diagnosis. We analyzed DWI sequences, in order to evaluate CMI incidence in this population, and compared it to control groups of patients with other undiagnosed malignancies and patients without known cancer. Results. Altogether, we reviewed 1822 MRI brain scans, of which 497 scans were taken in patients with undiagnosed lung cancer, 543 scans of noncancer patients, and 793 scans of patients with other undiagnosed malignancies. In the lung cancer group, we found 24 CMI, compared with 4 in the noncancer group ( p = 0.04 ) and 8 in the other cancer group ( p = 0.07 ). Conclusions. CMI is common in undiagnosed lung cancer patients compare to other undiagnosed cancer types or noncancer patients. At the time of lung cancer diagnosis patients may be at risk for future stroke or cognitive decline.

Lung cancer is associated with acute ongoing cerebral ischemia: A population-based study

“…CMI incidence among LC patients was significantly higher relative to non-cancer patients in our previously published cohort of non-cancer patients 26 (Supplementary Tables 4 and 5).…”

“…Our group had excellent inter-rater reliability. 26 Intraclass correlation coefficients (ICCs) 27 from two-way analysis of variance (ANOVA) analysis were 0.89 (95% confidence interval (CI) = 0.82–0.94) for CMI.…”

Association of Acute Incidental Cerebral Microinfarcts With Subsequent Ischemic Stroke in Patients With Cancer

“…Acute incidental CMI are extremely rare in the general population, with a prevalence of less than 1%. 3,10,26 However, the detection of a single lesion may imply an annual incidence of hundreds of CMI. 27 Owing to their rarity, no previous studies have investigated the risk of future stroke or TIA associated with acute incidental CMI.…”

“…CMI location (e.g., cortical vs subcortical) was also defined. We previously described our protocol for acute incidental CMI identification and exclusion of mimics 10,11 (see eMethods).…”

“…9 Our previous studies demonstrated the common occurrence of these lesions in patients with cancer, particularly lung cancer, before and after cancer diagnosis. 10,11 However, whether acute incidental CMI increases the risk of subsequent ischemic stroke in patients with cancer is unknown. Cancerrelated stroke (CRS) is an emerging subtype of ischemic stroke, characterized by unique pathomechanisms.…”