The effect of carotid and vertebrobasilar arterial blood flow on intracerebral metastasis in patients diagnosed with primary lung cancer

Objective: In this study, we aimed to contribute to the literature by evaluating the effect of carotid and vertebrobasilar artery diameter and blood flow on intracerebral metastasis in patients diagnosed with primary lung cancer at our hospital, thereby supporting early diagnosis and treatment. Materials and Methods: Diameter and blood flow measurements of the carotid and vertebrobasilar arteries were obtained using ultrasonography in patients diagnosed with primary lung cancer who were followed at the Selçuk University Faculty of Medicine Departments of Neurosurgery and Chest Diseases over a six-month period starting in May 2025. These data were statistically analyzed to evaluate their effect on intracerebral metastasis. Results: In our study; • The diameter and blood flow values of the left and right common carotid arteries (CCA), internal carotid arteries (ICA), and vertebral arteries (VA) measured by Doppler ultrasonography were compared between metastatic and non-metastatic groups. The median diameter and flow values for each vessel were similar between the two groups, and no statistically significant differences were observed in these parameters. • In subgroup analyses conducted to evaluate whether Doppler measurements obtained from the carotid and vertebral arteries had a significant effect on the lateralization, extent, and anatomical localization of metastasis, vessel diameter and blood flow measurements were found to be largely similar across the non-metastatic, unilateral metastatic, and bilateral metastatic groups when all three groups were considered together. • In the evaluation based on the number of metastases, comparisons between patients with solitary and multiple metastases demonstrated that both left and right vessel diameters as well as blood flow measurements largely overlapped among the groups, indicating that arterial hemodynamic parameters did not have a significant effect on the number of metastases. • It was observed that carotid artery diameter and blood flow data did not result in a significant difference in the supratentorial or infratentorial localization of metastases. • Infratentorial localization was considered one of the subgroups in which a potential hemodynamic correlation might be expected, particularly due to its association with the posterior fossa and vertebral circulation; however, no significant differences were observed in vertebral artery diameter or blood flow measurements. • In the non-metastatic group, 66.7% of the cases were diagnosed with squamous cell carcinoma and 27.1% with adenocarcinoma. In contrast, the metastatic group showed a markedly higher proportion of adenocarcinoma, reaching 65.9%, while squamous cell carcinoma accounted for only 22.7%. This pronounced difference in histopathological distribution between the two groups was found to be highly statistically significant. • When the intracerebral distribution was evaluated in detail, the vast majority of metastases were found to be located in the supratentorial region. This finding is consistent with data reported in the existing literature. Conclusion: We argue that the primary determinants of the metastatic process are tumor biology, microvascular interactions, and molecular adaptation mechanisms rather than macrovessel circulation. Keywords: Brain metastasis; carotid artery; diameter and blood flow measurements; Doppler ultrasonography; lung cancer; vertebrobasilar artery