Comparison of stereotactic radiosurgery (SRS) alone and whole brain radiotherapy (WBRT) plus a stereotactic boost (WBRT+SRS) for one to three brain metastases.
BACKGROUND
The best available treatment of patients with one to three brain metastases is still unclear. This study compared the results of stereotactic radiosurgery (SRS) alone and whole brain radiotherapy (WBRT) plus SRS (WBRT+SRS).


METHODS
Survival (OS), intracerebral control (IC), and local control of treated metastases (LC) were retrospectively analyzed in 144 patients receiving SRS alone (n=93) or WBRT+SRS (n=51). Eight additional potential prognostic factors were evaluated: age, gender, Eastern Cooperative Oncology Group performance score (ECOG-PS), tumor type, number of brain metastases, extracerebral metastases, recursive partitioning analysis (RPA) class, and interval from tumor diagnosis to irradiation. Subgroup analyses were performed for RPA class I and II patients.


RESULTS
1-year-OS was 53% after SRS and 56% after WBRT+SRS (p=0.24). 1-year-IC rates were 51% and 66% (p=0.015), respectively. 1-year-LC rates were 66% and 87% (p=0.003), respectively. On multivariate analyses, OS was associated with age (p=0.004), ECOG-PS (p=0.005), extracerebral metastases (p<0.001), RPA class (p<0.001), and interval from tumor diagnosis to irradiation (p<0.001). IC was associated with interval from tumor diagnosis to irradiation (p=0.004) and almost with treatment (p=0.09), and LC with treatment (p=0.026) and almost with interval (p=0.08). The results of the subgroup analyses were similar to those of the entire cohort. The increase in IC was stronger in RPA class I patients.


CONCLUSIONS
WBRT+SRS resulted in better IC and LC but not better OS than SRS alone. Because also IC and LC are important end-points, additional WBRT appears justified in patients with one to three brain metastases, in particular in RPA class I patients.
Rades
Dirk
D
Department of Radiation Oncology, University Hospital Schleswig-Holstein, Campus Luebeck, Germany. Rades.Dirk@gmx.net
Kueter
Jan-Dirk
JD
Hornung
Dagmar
D
Veninga
Theo
T
Hanssens
Patrick
P
Schild
Steven E
SE
Dunst
Juergen
J
D000367:Age Factors; D001932:Brain Neoplasms / Q000401:mortality / Q000532:radiotherapy* / Q000556:secondary / Q000601:surgery*; D015331:Cohort Studies; D003131:Combined Modality Therapy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011379:Prognosis; D016016:Proportional Hazards Models; D016634:Radiosurgery; D011879:Radiotherapy Dosage; D012189:Retrospective Studies; D012737:Sex Factors; D013997:Time Factors; D016896:Treatment Outcome