PROGNOSTIC FACTORS AND RESULTS OF RADIATION-THERAPY IN OPTIC PATHWAY TUMORS

Aims and Background: The role of radiotherapy in the management of pat ients with optic pathway tumors remains controversial. This study anal yzes the outcome of patients treated with radiotherapy and attempts to identify the groups of patients that may require early therapy, Metho ds: We retrospectively reviewed 36 patients with optic pathway tumors treated with radiotherapy alone (26 patients) or with postoperative ra diotherapy (10 patients). Seven patients had optic nerve tumors and 29 patients had chiasmal tumors. The actuarial progression free survival and observed survival probabilities were calculated using the Kaplan- Meier method and differences between curves were evaluated by the Mant el-Cox test. The obtained significant variables in the univariate anal ysis were analyzed using the Cox proportional hazards model. Results: The 10-year actuarial progression-free survival (10-y PFS) rate was 86 % for patients with optic nerve gliomas and 47% for patients with chia smal tumors. The 10-year actuarial observed survival (10-y OS) rate wa s 75% for patients with optic nerve gliomas and 53% for patients with chiasmal gliomas. In the group of patients with chiasmal tumors, progr ession-free survival and observed survival rates were significantly lo wer in infants (10-y PFS: 30%; 10-y OS: 37%), in patients with neurolo gical deficits 10-y PFS and 10-y OS: 23%), in patients with signs of e levated intracranial pressure (10-y PFS and 10-y OS: 9%), with hydroce phalus (10-y PFS and 10-y OS: 0%), or with impairment of consciousness (10-y PFS and 10-y OS: 17%). Evaluation by computed tomography scanni ng was associated with a significantly higher probability of PFS. Radi ation doses lower than 50 Gy were associated with significantly lower PFS and OS rates. In the Cox multivariate analysis, presence of neurol ogical deficits and radiation dose significantly influenced observed s urvival. Presence of hydrocephalus significantly influenced progressio n-free survival. Conclusions: The prognosis of patients with chiasmal gliomas presenting with neurologic deficits is poor and should be trea ted at diagnosis. A minimum tumor dose of 50 Gy is recommended.