gms | German Medical Science

Objective: Pilocytic astrocytomas (PA) are in general tumors of childhood and adolescence. They present as a circumscribed slow-growing lesion usually found in the cerebellum and optic-hypothalamic region, but it can be localized in the cerebral hemispheres. It is the most common glioma in children, 62% of astrocytomas in children being PA. But there is a certain number of PA occurring in adults. In our prospective observational data base of neuroepithelial tumors 29 adult patients with PA are registered.

Methods: 29 adult patients with PA have been operated upon between 1953 and 2008. Mean age at time of operation was 38 years (19 to 65). In eleven patients the tumor was localized in the posterior fossa, the others were suprasellar, frontal, temporal, parietal, occipital and basal ganglia. In 14 patients the tumor was totally resected. In the others removal was subtotal (4patients) or partial (7 patients). In four patients a biopsy was done.

Results: Follow-up (1 month to 54 years) was done routinely with clinical exam and MRI every three months in the first year after the operation and then, time interval was enlarged. No adjuvant therapy was done except in one case with rapid progression after biopsy. Recurrence or progression of residual tumor occurred in 8 patients respectively after 2, 4 and 7 months, after 2½, 10, 17, 19 and 27 years. 7 of these 8 patients had a residual tumor. In 3 patients a second operation was done, two of them have been operated upon for a second recurrence. The other patients are in observation with stable disease except 3. The patient with progression after 2 months died 9 months after diagnosis. Two patients died during follow-up, one after 2,5 years due to metastases of a carcinoma of the prostate, the other after 54 years due to an ovarian cancer.

Conclusions: PA is the most benign variant of astrocytic tumors in the WHO classification. It is a rare tumor entity in adults, accounting for 3% of all neuroepithelial tumors in our series. Optimal treatment is total tumor removal if feasable without neurological deficits. Recurrence of completely resected tumor is rare. But even in case of incomplete removal the remnants of the tumor may not progress. In case of progression or recurrence patients should be offered a second operation in order to improve long-term prognosis. There is no indication for adjuvant therapy except in selected cases. Follow-up with MRI is mandatory to discover recurrences and to decide further treatment.