Marked elevation of carcinoembryonic antigen and carbohydrate antigen 19-9 in the peripheral blood as an initial manifestation of meningeal carcinomatosis.

Marked elevation of tumor markers in the peripheral blood was initially a sole manifestation of meningeal carcinomatosis in a man with gastric carcinoma. In addition to extensive meningeal carcinomatosis, no metastatic lesions were found at autopsy other than microscopic infiltration into a tiny paraaortic lymph node. Elevation of these markers in the peripheral blood is best explained by meningeal carcinomatosis. When elevation of these markers is otherwise unexplainable, meningeal carcinomatosis should be considered as a diagnostic possibility even in the absence of neurological symptoms.