Correct answer: Both the saggital and the coronal MRI images show a lesion in the pituitary fossa, most likely a hemorrhagic pituitary adenoma. Differential diagnosis includes a Rathke’s cleft cyst. Pituitary tumours are practically always benign. The are three hostological types of pituitary adenoma: 1) chromophobe (70%, many are non-secretory) 2) acidophil (15%, secrete GH or PRL) 3) basophil (15%, secrete ACTH)