Faculty Bibliography

AIMS: We analyzed the efficiency of the Leksell Gamma Knife Perfexion (LGK PFX) in the treatment of multiple metastases and benign tumors. We also compared treatment planning conformity between LGK PFX and LGK 4C for benign tumors. METHOD: Over a 6-week interval, 37 patients (21 with multiple brain metastases and 16 with benign tumors) underwent radiosurgery using LGK PFX at the University of Pittsburgh. We created dose plans for all patients using Leksell Gamma Plan for LGK PFX and LGK 4C. The same doses were prescribed for both LGK PFX and LGK 4C. RESULTS: No significant difference was observed between LGK 4C and LGK PFX for total beam-on time. The median reduction in setup time on the LGK PFX was 53 min per patient (range 19-125 min) for multiple metastases. The median reduction in setup time on the LGK PFX for benign tumors was 16 min per patient (range 5-53 min). There was no significant difference in the dose conformality between LGK 4C and LGK PFX. CONCLUSIONS: This study demonstrated that in addition to its enhanced cranial reach, LGK PFX provided a significant improvement in efficiency for patients with multiple brain metastases. For benign tumor radiosurgery LGK PFX provided improvement in efficiency without a significant difference in conformality.

A consortium of translational stem cell and stroke experts from multiple academic institutes and biotechnology companies, under the guidance of the government (FDA/NIH), is missing. Here, we build a case for the establishment of this consortium if cell therapy for stroke is to advance from the laboratory to the clinic.

We evaluated 20 pineal parenchymal tumor patients who underwent radiosurgery at our institution over a 20-year period. Thirteen patients had pineocytoma, 5 patients had pineoblastoma and 2 patients had mixed pineal parenchymal tumors. The median radiosurgery prescription dose to the tumor margin was 15.0 (12-20) Gy. At an average of 54.1 (range, 7.7-149.2) months, 6 patients had died and 14 patients were living. The overall survival after radiosurgery was 95.0, 68.6, and 51.4% at 1, 5 and 10 years, respectively. Patients with pineocytomas had 1-, 3- and 5-year overall survivals of 100, 92.3 and 92.3%, respectively. In 19 patients who were evaluated with imaging, 5 (26%) demonstrated complete regression, 9 (47%) had partial regression, 2 (11%) had stable tumors and 2 (11%) showed local in-field progression. The progression-free survival after stereotactic radiosurgery for all type of pineal parenchymal tumors was 100, 89.2 and 89.2% at 1, 3, 5 years after radiosurgery, respectively. Stereotactic radiosurgery is an effective and safe alternative to the surgical resection of pineocytomas as well as part of multimodal therapy for more aggressive pineal parenchymal tumors.

PURPOSE: To evaluate adjuvant stereotactic radiosurgery (SRS) in the management of recurrent or residual intracranial hemangiopericytomas (HPCs), we assessed tumor control, survival, and complications in patients who had undergone gamma knife SRS as part of multimodal therapy. METHODS AND MATERIALS: We retrospectively reviewed the records of consecutive 20 HPC patients who had undergone SRS for 29 tumors. The median patient age was 51.5 years (range, 8.9-80.2). All patients had undergone previous surgical resection of their tumors. In addition, 12 patients underwent fractionated radiotherapy before SRS. Of the 20 patients, 16 patients had low-grade HPCs (20 tumors) and 4 had high-grade anaplastic HPCs (9 tumors). The median radiosurgery target volume was 4.5 cm(3) (range, 0.07-34.3), and the median marginal dose was 15.0 Gy (range, 10-20). RESULTS: At an average of 48.2 months (range, 7.2-124.1), 5 patients had died of metastases and 3 patients had died of disease progression. The overall survival after radiosurgery was 100%, 85.9%, and 13.8% at 1, 5, and 10 years, respectively. The follow-up imaging studies demonstrated tumor control in 21 (72.4%) of 29 tumors. The progression-free survival rate after SRS at 1, 3, and 5 years was 89.1% for low-grade HPCs and 88.9%, 66.7%, and 0%, respectively, for high-grade HPCs. The factors associated with improved progression-free survival included lower grade and higher marginal dose. Eight patients had intracranial or extracranial metastasis after the initial diagnosis, which correlated with the shorter survival. CONCLUSION: The results of our study have shown that adjuvant SRS after tumor resection is an important management option for patients with residual or recurrent HPCs and is particularly effective for less-aggressive tumors.