Brain Pathology Case of the Month - August 2004


DIAGNOSIS:   PILOCYTIC ASTROCYTOMA

DISCUSSION:

Pilocytic astrocytoma is a quite rare intramedullary neoplasm in the adult. In a well documented series of 177 resected tumors only four cases have been found (1). Since 1984 at the Department of Neurosurgery in Hamburg 226 patients harboring an intramedullary tumor underwent surgery, including ten cases with pilocytic astrocytoma (Table 1). The diagnosis of pilocytic astrocytoma required following criteria: bipolar cells, Rosenthal fibers, microcysts and a mixture of spongy and dense tissue architecture (2). The presented patient is the only one older than 60 years. During the same time span 117 patients affected by an intracranial pilocytic astrocytoma have been operated and again, only three of them were over 60 years old. The combination of spinal location and age over sixty is so far unique.

The very slow onset and the particularly misleading feature of the abdominal symptomatology should also be noticed. Even in children, where the incidence of pilocytic astrocytoma is not so rare, only two cases with abdominal pain as first symptom of a spinal cord tumor have been reported (3) . In our case additional gait disturbance and disturbance of micturition led to a high quality MRI investigation allowing for the diagnosis of a thoracic intramedullary space occupying lesion.

The microscopic examination of samples taken from three distant areas of the exophytic tumor confirmed the typical histological pattern of pilocytic astrocytoma. Interestingly, the different pictures were almost identical so that the same cellular array has to be assumed for the intramedullary part of the tumor.

REFERENCES:

  1. Miller DC (2000) Surgical pathology of intramedullary spinal cord neoplasms. J Neuro-Oncol 47: 189-194.
  2. Burger PC, Scheithauer BW, Paulus W, Szymas J, Giannini C, Kleihues P (2000) Pilocytic astrocytoma. In: pathology and genetics of tumors of the nervous system; Kleihues P, Cavanee WK (eds.): 29-39. International Agency for Research on Cancer: Lyon.
  3. Eeg-Olofsson O, Carlsson E, Jeppsson S (1981) Recurrent abdominal pains as the first symptom of a spinal cord tumor. Acta Paediatr Scand 70(4):595-7.

Contributed by Luca Papavero, Christian Hagel, Ulrich Grzyska, Eric Fritsche and Manfred Westphal


International Society of Neuropathology