322P - Re-treatments after gamma knife radiosurgery for metastatic brain disease

Date 10 October 2016
Event ESMO 2016 Congress
Session Poster display
Topics Surgical Oncology
Therapy
Radiation Oncology
Presenter Deirdre Ten Berge
Citation Annals of Oncology (2016) 27 (6): 100-102. 10.1093/annonc/mdw366
Authors D.M. Ten Berge1, Z. Sadik2, G.N. Beute2, S. Leenstra2, B. van der Pol2, J.H.B. Verheul2, P.E.J. Hanssens3
  • 1Radiology, St. Elisabeth Hospital, 5022GC - Tilburg/NL
  • 2Neurosurgery, St. Elisabeth Hospital, Tilburg/NL
  • 3Gamma Knife Center Tilburg, St. Elisabeth Hospital, Tilburg/NL

Abstract

Background

Gamma Knife radiosurgery (GKR) has become a first-line treatment option for brain metastases resulting in high local tumor control. As systemic therapies improve and survival prolongs, local recurrences and new brain metastases are more likely to occur following GKR, with may increase the need for secondary treatments. In this report we evaluated the number of patients receiving re-treatments, the timing and kind of re-treatments, as well as the survival after treatment of local recurrences and new brain metastases in a group of patients initially treated with GKR alone.

Methods

We performed a retrospective analysis of 806 patients with histologically confirmed metastatic cancer, of all primary origins, who underwent GKR in our center between January 2009 and December 2014. All the brain metastases that were visible on the high resolution triple dosed gadolinium planning MR imaging (n = 2180) were treated. In all cases, a dose of 18-25 Gy was prescribed to the isodose covering 99-100% of the tumor volume. All patients had a Karnofski index ≥70 and had no prior treatment to the brain.

Results

A median survival of 6 months (95%CI: 5.3-6.7) was found in the studied population (n = 806; 51% male; mean age 63 years). Per patient a median of two brain metastases were treated at first GKR (Range 1-15). Retreatment was given to 289 patients (36%) out of whom 69% received GKR as the second treatment, 14% received whole brain radiotherapy (WBRT), 12% underwent resection and 5% received other re-treatments. Patients receiving re-treatment had a median survival of 13 months (95%CI: 11.3-14.7) versus patients not receiving re-treatment with a median survival of 4 months (95%CI: 3.6-4.4). The median interval between the first GKR and the second treatment was 6 months. Out of the deceased patients most died within the first 3 months (35%). Most patients died due to their extracranial disease (61-66%).

Conclusions

About one third of patients treated with GKR for brain metastases in our center received a secondary treatment to the brain along the course of their disease. Repeat GKR was given to the majority of these patients. Re-treatment of new brain metastases or local recurrence appeared to be an effective therapy as most patients died due to extracranial disease.

Clinical trial identification

Legal entity responsible for the study

Dr. Hannsens, Gamma Knife Center Tilburg

Funding

Gamma knife center Tilburg

Disclosure

All authors have declared no conflicts of interest.