ESTRO 36 _______________________________________________________________________________________________The time to BM in patients with HER-2 positive was shorter than Luminal-A like (20.5 vs. 89.0months，p<0.001).Median overall survival (OS) after BM was significantly associated with Breast-GPA 0-1, 1.5-2, 2.5-3 and 3.5-4 were 4.3, 14.0, 14.8 and18.2months, respectively (p =0.012, fig A).Univariate analysis found that KPS at the diagnosis of BM, infra-tentorial metastases, total doses and systemic therapy after WBRT were significantly associated with OS after BM (p< 0.05).The multivariate analysis showed infra-tentorial metastases, total doses and systemic therapy after WBRT were independent prognostic factors for OS after BM(p <0.05).The median OS was significantly improved in HER-2 + patients receiving anti-HER2 therapy after WBRT (25.4 vs. 5.6 months, p = 0.040).Also, the median OS was significantly improved in GPA 1.0-2.0patients who received upfront WBRT (14 vs. 7.9 months, p = 0.012).The proportion of occurrence of intracranial progress for hormone receptor (HR) negative patients was higher than HR positive (51.4 % vs. 27.5 %, p = 0.018). ConclusionThe breast cancer molecular subtype is an important prognostic factor in BCBM.The patients with infratentorial metastases, radiation dose of less than 40Gy or no systemic treatment after WBRT are associated with worse OS.Patients with HR negative disease were more likely to develop intracranial progress.Those with less favorable prognosis according to Breast-GPA may benefit from the upfront WBRT.

Objectives: To evaluate the efficacy and safety of Gamma Knife Radiosurgery (GKRS) in the treatment of single and multiple brain metastases.Patients and methods: From October 2012 to June 2014 106 patients were treated with Radiosurgery (RS) for brain metastases at University of Florence. 77 out of 106 patients had a radiological follow up and their data were analyzed. The target was defined as the enhancing lesion. The prescription dose was defined depending on tumor volume and tumor location. Each patient performed an MRI one month after GKRS for the first three months and every 3 months thereafter. Overall survival was calculated from the day of RS until death. Local recurrence (LR) was defined as radiologic growth of the irradiated lesion, while distant brain recurrence (DBR) was the evidence of brain lesion outside the previous irradiated field. Both the LR and DBR were calculated from the RS till the day of radiological evidence of relapse. The correlations within patient and disease characteristics and the outcomes of survival and disease control were analyzed.Results: Mean follow up was 7.2 +/- 4.8 months (range: 2.4-22.8 months). At the time of analysis 21 patients (273%) were dead. The overall survival (OS) at 1 year was 74%. On univariate Cox Regression analysis female gender (p = 0.043, HR: 0.391, 95% CI: 0.157-0.972) and age >65 years (p = 0.003 HR: 4.623, 95% CI: 1.687-12.663) were predictive for survival. On multivariate analysis, age older than 65 years (p = 0.005HR: 4.254, 95% CI: 1.544-11.721) was confirmed as associated with worsened overall survival. 19 patients (24.7%) had recurrence in the radiosurgery field. The median time to local failure was 4.8 +/- 2.0 months (range: 1.8-9.4 months) from GKRS. On Cox Regression univariate analysis, the only factor associated with higher risk of local failure was a number of treated lesions more than 4 (p = 0.015, HR: 3.813, 95% CI: 1.298-11.202), no significant parameters were found at the multivariate analysis. The median time to develop distant brain failure was 6 +/- 4.32 months (range: 1.08-21.6 months). Median distant brain control was 74% at 1 year. None of the factors analyzed was statistically significant for the distant brain relapse. The radiosurgery treatment was well tolerated. One patient treated for seven metastases developed seizures 8 h after GKRS, he was treated with steroids and anticonvulsants. One patient had radiologic evidence of radionecrosis without any neurological symptoms.Conclusions: In well-performing patients with stable systemic disease radiosurgery can be performed as an exclusive treatment for brain metastases. Younger patients could have a greater benefit from the RS, on the other hand our finding confirm no correlation between the survival outcome and the number of lesions treated. (C) 2015 Elsevier B.V. All rights reserved.

INTRODUCTION: Accurate assessment of the exact number of brain metastases is of utmost importance in the decision-making process for the appropriate treatment. The diagnostic efficacy in the detection of additional brain metastases of a double dose contrast three-dimensional, T1-Weighted Gradient-Echo Imaging was evaluated. METHODS: Before undergoing radiosurgical treatment, patients underwent a brain magnetic resonance imaging (MRI) scan to be used during the treatment planning in order to contour the targets and to locate the brain lesions as they relate to the stereotactic frame. All the patients underwent a post-contrast study with T1-weighted, 3D Magnetization-Prepared Rapid Acquisition Gradient Echo (MP RAGE) sequence. We used a double dose of gadobenate dimeglumine and slice thickness of 0.9 mm. RESULTS: Starting from October 2012 to February 2014, we treated with Gamma Knife radiosurgery (GKRS) 62 patients with brain metastases. On the diagnostic MRI, all the patients had a number of lesions ≤4. Median time interval between diagnostic MRI scan and the day of GKRS was 11 days (range 5-20) A total of 54 additional lesions were detected on MR imaging performed in the same day of the GKRS in twenty-two patients out of 62 (35.5%). A median number of 2 additional lesions were detected (range 1-8). Among these 22 patients only 14 patients had a number of lesions ≤4 on the day of treatment. Patients with a total number of lesions ≤10 were treated with GKRS. Two patients with a total number of lesions > 10 were treated with whole brain radiotherapy (WBRT). CONCLUSIONS: A double-contrast study with T1-weighted, volumetric MPRAGE sequence may offer better staging for patients with brain metastases. In our opinion, it should be recommended in all the patients with newly diagnosed brain metastases because the detection of the real number of lesions is crucial for an adequate treatment and it also may lead to choose different therapeutic strategies.