Impact of features of brain lesion in prognosis.

Abstract

e13549 Background: Brain metastasis (BM) is an event with poor prognosis. Different scores predict outcome in patients with BM. One of them is Graded Prognostic Assessment (GPA) score and includes clinical features like age and performance status of the patients. The frequency of patients with available tissue from brain lesions is increasing because of improvement of surgical techniques. It allows to include the evaluation of pathological features in order to improve prognosis determination. Our study aims to evaluate if tumoral proliferation and lymphocyte infiltration in brain lesions can improve prognostic accuracy of clinic-pathological features in patients with BM. Methods: We obtained BM samples from 113 cases that came to the Instituto Nacional de Enfermedades Neoplasicas from 2001 to 2015. We evaluated clinicopathological features from patient files and prospectively evaluated pathological features: Ki67 and lymphocytes in 64 BM lesions from slides scanned in a BX63-Olympus. The image analysis software use for calculating KI67 index and CD3 was Tissuemorph, with a median count of 5135 cells and 5391 cells, respectively. We calculated GPA score and evaluated the value to add pathological features of BM. We also evaluated distribution of mononuclear cells. Results: Median age at first diagnosis of BM was 52 years (range 11–75 years), 35.4% were male. BM at debut and extra-brain disease was found in 33.6% and 39.3%. The most frequent primary tumor location was breast (31%) and lung (18.6%). Most frequent procedure for brain lesion was biopsy (9.8%), subtotal resection (8.9%) and total resection (81.3%). Distribution of lymphocytes was perivascular in 57 cases. Median ki67 and CD3 TIL were 30 and 44, respectively. GPA 0-1, 1.5-2.5, 3 and 3.5-4 were found in 18 (16.2%), 61 (55.0%), 27 (24.3%) and 5(4.5%), respectively. Higher GPA (p = 0.196) had a trend to shorter survival. Higher ki67≥ 15% (p = 0.013) index was associated with shorter survival. The CD3 lymphocytes count was not associated with survival (p = 0.754). Adding ki67 index to GPA was associated with better outcome (p = 0.033). Conclusions: Our results find that patients with high ki67 index in brain lesions carry a worse prognosis and adding this information to GPA score can improve prognostic accuracy of the tool.