RESUMEN
Background: It is important to make the accurate diagnosis of leptomeningeal metastasis(LM) because the institution of appropriate therapy may produce symptomatic improvement, prevent neurologic deterioration, and prolong survival. To evaluate the appropriate diagnostic methods of LM, we conducted the comparison of diagnostic yield in each diagnostic method and analyzed factors influencing the diagnostic results. METHODS: We analyzed 62 patients of LM with following inclusion criteria: positive CSF cytology, or abnormal neuroimaging, or elevated CSF biochemical marker, or characteristic clinical symptom and abnormal routine CSF examination. RESULTS: Primary cancer of LM was following; lung cancer 21, lymphoma 15, stomach cancer 13, breast cancer 9, rhabdomyosarcoma 2, bladder cancer 1, and colon cancer 1. The positive yield in the diagnosis of LM was 54.5% in CSF cytology, 55.9% in neuroimaging, 62.5% in CSF biochemical marker. As each diagnostic method was combined, the positive yield was increased to 86.4-88.5% with the highest in combination of CSF cytology with neuroimaging. The relationship between CSF cytology and neuroimaging is complementary in the diagnosis of LM (p=0.01). In positive group of CSF cytology, the count of CSF WBC was higher than in negative group (p=0.026), and clinical feature revealed a tendency of combined cerebral and cranial symptom than isolated symptom. The interval from the diagnosis of primary cancer to diagnosis of LM was most prolonged in breast cancer with a mean of 38.2 month. CONCLUSIONS: Combination of each diagnostic method increases the diagnostic yield, and CSF cytology and neuroimaging must be performed with each other.