Immunohistochemical analysis of the cerebrospinal fluid for carcinomatous and lymphomatous leptomeningitis

To evaluate the sensitivity and specificity of immunohistochemical analysis in relation to the standard cytological examination of the cerebrospinal fluid (CSF) in patients with either a solid tumour or a haematological malignancy and possible leptomeningeal disease, 68 CSF-samples derived from 68 patients were examined. The sensitivity of immunohistochemical analysis was 0.54 and its specificity 0.98. Only one patient had a positive immunohistochemistry and a negative cytology. The gain of adding immunohistochemistry to cytology is nearly 8%. It is concluded that immunohistochemistry should not be used as a screening test for leptomeningeal disease in patients with cancer.