[Collision sellar lesions: pituitary adenoma and Rathke cleft cyst]

Rathke's cleft cyst (RCC) are a slow-growing, benign, cystic lesions that arises from the remnants of the primitive ectoderm and Rathke's pouch. They present a common origin with pituitary adenomas (PA), however, the concomitant presentation of a PA and a RCC rarely occur. We present a case of a 41-year-old female with Cushing's disease. Magnetic resonance imaging (MRI) showed two synchronic lesions in the sellar region. An endoscopic transnasal approach was performed, with complete excision of both. The histological studies revealed an ACTH secreting PA and a RCC. The patient presented clinical and endocrinological remission six months after surgery. With the presence of cystic lesion at the sellar region, and the concomitant finding of a pituitary adenoma, RCC should be considered.