Cytopathologic Diagnosis of Lymphomas in Serous Effusions, Cerebrospinal and Vitreous Fluid

Cytologic evaluation of fluids containing lymphocytes provides valuable information regarding the nature of these lesions. Accurate cytologic diagnosis, with clinicopathologic correlation and judicious use of ancillary testing where possible, is essential for identifying the underlying cause of effusion, guiding therapy, monitoring disease progression or relapse, and informing prognosis. To optimize diagnostic outcomes, proper collection, transport, and preparation of fluid specimens is required. Collaboration with haematopathologists and use of standardized cytologic reporting systems further contribute to diagnostic accuracy and consistency. Emerging technologies, including molecular profiling, liquid biopsy, single-cell multi-omics and artificial intelligence, offer promising avenues for advancing the diagnosis and prognostication of haematolymphoid malignancies in fluid-based samples. Further research will determine their clinical utility.