Meningeal carcinomatosis (MC) is a malignant infiltration of the leptomeninges and subarachnoid space and can be a devastating complication of a systemic malignancy. Although often found in patients with known metastatic malignancies, MC can also be the initial manifestation of an underlying malignancy. We report four case studies where back pain, dizziness, cognitive decline, headache and headache with the cranial nerve VI palsy were the first signs of MC. In two cases, adenocarcinoma ventriculi was found, in other one, the markers of the gastrointestinal tract malignancy were highly positive but malignity was not found, and in the last one, there was a known breast carcinoma. The diagnosis of MC requires the finding of malignant cells in the cerebrospinal fluid, but sometimes several lumbar punctures are required to establish the diagnosis, and also MRI with gadolinium. Finally, we would like to highlight the fact that markedly decreased glycorrhachia in cerebrospinal fluid (CSF) can also be the first sign of MC (Fig. 6, Tab. 2, Ref. 23).