CEACAM5 and neoplasm: In another study focusing on the value of CEA in differentiating intracranial metastasis from other neoplasms, Batabyal detected mean CSF CEA levels of 6.3 mg/ml, 0.92 ng/ ml, 0.31 ng/ml, 0.22 ng/ml in intracranial metastasis, intracranial primary tumor, benign tumor and normal control, while those of blood CEA levels were 5.2 ng/ml, 3.0 ng/ml, 2.7 ng/ml and 2.5 ng/ml respectively [16].