Significance of Primary Tumor Location and Histology for Brain Metastasis Development and Peritumoral Brain Edema in Lung Cancer

Background: Brain metastasis of lung cancer adversely affects overall survival (OS) and quality of life, while peritumoral brain edema is responsible for life-threatening complications. Methods: We retrospectively analyzed the clinicopathological and cerebral radiological data of 575 consecutive lung cancer patients with brain metastases. Results: In adenocarcinoma and squamous cell carcinoma, peritumoral brain edema was more pronounced than in small-cell lung cancer (p <0.001 and p <0.001, respectively). There was a positive correlation between the size of metastasis and the thickness of peritumoral brain edema (p <0.001). It was thicker in supratentorial tumors (p = 0.019), in younger patients (= 50 years) (p = 0.042), and in females (p = 0.016). The time to development of brain metastasis was shorter in central than in peripheral lung cancer (5.3 vs. 9.0 months, p = 0.035). Early brain metastasis was characteristic for adenocarcinomas. A total of 135 patients had brain only metastases (N0 disease) characterized by peripheral lung cancer predominance (p <0.001) and a longer time to development of brain metastasis (9.2 vs. 4.4 months, p <0.001). OS was longer in the brain only subgroup than in patients with N1-3 diseases (p <0.001). Conclusions: The clinicopathological characteristics of lung cancer are related to the development and radiographic features of brain metastases. Our results might be helpful in selecting patients who might benefit from prophylactic cranial irradiation. (C) 2016 S. Karger AG, Basel