Journal of Radiosurgery, Vol. 1, No. 1, 1998

Brief Commentary

On "Radiosurgery for Tumors in the Body: ClinicalExperience Using a New Method" (Blomgren et al., ThisIssue)

Blomgren et al. report on their clinical experiencewith nonskeletal fixation in extracranial stereotactic ra-diosurgery in 100 cases without skeletal fixation be-tween 1991 and 1996. The authors employed astereotactic frame with a mean reproducibility of 3.7 mmin the transverse plane and 5.7 mm in the longitudinalplane and therefore added a margin of 5 mm to the clin-ical target volume in the transverse plane and 10 mm inthe longitudinal direction for appropriate margins aroundthe target volume. The authors employed anywhere fromfive to nine stationary coplanar or noncoplanar beamsand employed secondary blocks or a multileaf collimatorfor further collimation. Their results are very promisingfor making an eloquent case for extracranial stereotacticradiosurgery.

With respect to primary hepatic tumors, the authorsreport no local failures in 17 patients, with a mean sur-vival time for this group of 13.4 months. Likewise, atotal of 21 hepatic metastases was treated in 17 rumors,with only one local and one regional recurrence. A totalof 17 thoracic tumors was treated, with only one localfailure. Nineteen extrahepatic abdominal tumors werealso treated, with only two failures. Overall, the authorsreport a remarkable failure rate of only 4 of the 75 ra-diographically evaluated tumors. Some of these earlyfailures may have been attributable to radiation dosesthat were too low, and other early failures to the fact

that there was overgrowth of the tumor from foci adja-cent to the treated area.

The authors appropriately remark on the sophisti-cation of radiographic imaging required for these treat-ments and the significant physics issues of suchradiosurgical treatment. Nonetheless, this is a hallmarkpaper in that it establishes a significant benchmark interms of using stereotactic radiosurgical technique totreat targets throughout the body. Naturally, it signals tous that we should be skeptical and conservative beforeembracing new technology. However, at the same time,there appears to be significant hope for pursuing largerclinical studies to evaluate this promising new technol-ogy in the control of extracranial neoplastic disease. Thisarticle marks the dawning of a new period in stereotacticradiosurgery in which we are finally able to bring radio-surgery outside the confines of the skull and any targetin the body can begin to be assessed in terms of stereo-tactic technologies.

Allan Hamilton, M.D., FACSDepartment of NeurosurgeryThe University of ArizonaHealth Science Center1501 North Campbell AvenueTucson, Arizona 85724-5070

751096-4053/98/0300-0075S15.00/0 © L998 Plenum Publishing Corporation