Purpose: To retrospectively evaluate the effectiveness of fractionated ster
eotactic radiotherapy (FSRT) in patients with small intracranial malignanci
es.
Methods and Materials: From July 1991 to March 1997, 80 patients with a tot
al of 121 brain or skull-base tumors were treated with FSRT alone, and were
followed for periods ranging from 3 to 62 months (median 9.8). The majorit
y of patients received 42 Gy in 7 fractions over 2.3 weeks, but in July 199
3, protocols using smaller fraction doses were introduced for patients whos
e radiation-field diameters were larger than 3 cm or whose tumors were clos
e to critical normal tissues.
Results: For 64 patients with metastatic brain tumors the overall median su
rvival was 8.3 months and 1-year actuarial survival rate was 33%. Significa
nt prognostic factors were: the presence of extracranial tumors, pre-treatm
ent performance status, and the lung as a primary site. Patients without ex
tracranial tumors prior to FSRT had a median survival of 21.2 months. For s
even patients with high-grade glioma, 1-year actuarial local control rate w
as 75%, with a median survival of 10.3 months. For patients with skull-base
tumors the local control was achieved in 6 of 6 patients (100%), with a me
dian survival of 30.7 months. No one suffered from acute complications, but
three patients, two of whom had undergone FSRT as the third course of radi
otherapy, developed late radiation injuries.
Conclusion: Overall high local control and low morbidity rates suggest that
FSRT is an effective and safe modality, even for those with a history of p
rior irradiation. However,, patients with risk factors should be treated wi
th smaller fraction doses. (C) 1998 Elsevier Science Inc.