Abstract

Background: Leptomeningeal metastasis (LM) is a condition that develops when malignant cells from an extrameningeal primary tumor invade the leptomeninges. Patients with solid tumors (5-8%) and patients with lymphohematopoietic neoplasms (5-15%) are both diagnosed with it. Among solid tumors, leptomeningeal metastases are most frequently caused by metastases to the breast and lungs. The management of the patient depends on the early detection of LM. Cerebrospinal fluid (CSF) cytological analysis is still essential for LM diagnosis. The molecular subtypes of breast cancer should affect LM propensity because they are correlated with tumor behavior and prognosis.
Methodology: Records of patients who underwent CSF examination and had meningeal involvement with clinical symptoms were kept for seven years at an oncology facility in North India. The data was analyzed for CSF involvement in the tumor subtypes after the cases were divided into molecular subtypes by hormone receptor profiling, HER2, and the proliferation index of the breast tumors.
Results: Of the 1332 patients at our hospital who were diagnosed with breast cancer during the study period, 41 patients (3%) had CNS symptoms, and 22 patients (53% of them) had LM confirmed by CSF cytology. The majority of these (40.9%) belonged to the molecular subtype of triple-negative breast cancer, which was followed by HER2 (36.36%), Luminal A (13.63%), and Luminal B (9.09%).
Conclusion: The results show that triple-negative breast cancer is more likely than other subtypes to metastasize to the CNS, which is consistent with its more aggressive behavior. As a result, complications like leptomeningeal metastasis may be predicted by the molecular subtyping of breast carcinoma.