Surgical Resection of Brain Metastases and the Risk of Leptomeningeal Recurrence in Patients Treated with Stereotactic Radiosurgery
Menée à partir de données portant sur 330 patients présentant 1 à 4 métastases cérébrales traitées par chirurgie stéréotaxique entre 2006 et 2013 (durée médiane de suivi : 9 mois), cette étude évalue l'effet de la résection préalable des métastases sur le risque de maladie leptoméningée, puis identifie les facteurs prédictifs associés à ce risque
Purpose : Recent prospective data have shown that patients with solitary or oligometastatic disease to the brain may be treated with upfront stereotactic radiosurgery (SRS) with deferral of whole brain radiotherapy (WBRT). This has been extrapolated to the management of patients with resected lesions. The aim of this study was to assess the risk of leptomeningeal disease (LMD) in patients treated with SRS to the postsurgical resection cavity for brain metastases compared to patients treated with SRS to intact metastases. Methods and Materials : 465 patients treated with SRS without upfront WBRT at a single institution were identified; 330 of these with at least 3 months’ follow-up were included in this analysis. 112 patients had surgical resection of at least 1 lesion prior to SRS compared to 218 treated for intact metastases. Time to LMD and overall survival (OS) time were estimated from date of radiosurgery, LMD was analyzed using cumulative incidence method with death as a competing risk. Univariate and multivariate analyses were performed using competing risk regression to determine if various clinical factors predicted for LMD. Results : With a median follow-up of 9.0 months, 39 patients (12%) developed LMD at a median of 6.0 months after SRS. At 1 year, the cumulative incidence of LMD, with death as a competing risk, was 5.2% for the patients without surgical resection vs 16.9% for those treated with surgery (Gray’s test, p<0.01). On multivariate analysis, prior surgical resection (p<0.01) and breast pathology (p=0.03) were significant predictors of LMD development. Median OS time for patients undergoing surgery compared to SRS alone was 12.9 and 10.6 months respectively (Log-rank p=0.06). Conclusions : In patients undergoing SRS with deferral of upfront WBRT for intracranial metastatic disease, prior surgical resection and breast pathology are associated with an increased risk of developing LMD.