Introduction: Brainstem metastasis is a very rare revealing feature of lung carcinoma.
Exegesis: We report two cases of brainstem metastasis revealing lung carcinoma. In the first case, diagnosis was made on stereotaxic biopsy. In the second, the biopsy was not necessary as lung lesion was observed on thoracic CT-scan. Diagnosis of metastasis is difficult when a brainstem tumor occurs.
Conclusion: Stereotaxic biopsy is an interesting tool to distinguish between primary lesion and metastasis, but only when diagnosis work-up of primary cancer is negative.