Cerebrospinal lesions simulating central nervous system neoplasm.

There is a significant number of inflammatory, vascular or demyelinating diseases which may simulate clinically and radiologically primary or metastatic neoplasms of CNS. An incorrect diagnosis of CNS tumor may cause a fall of treatment plans including radiation therapy and chemotherapy. Not infrequently to define a correct diagnosis such cases require surgical procedures. The present report reviews the pathologic features of these space-occupying lesions presenting with signs and symptoms suggestive of brain neoplasms. Surgical pathologists may encounter diagnostic difficulties particularly when dealing with small tissue samples. The knowledge of basic histological features of these non-neoplastic conditions or the application of immunohistochemical and in situ hybridization techniques are essential to their recognition.