Background: Lymphocytic hypophysitis is a rare inflammatory lesion in the sellar region. Lymphocytic hypophysitis secondary to ruptured Rathke cleft cyst (RCC) is even more rarely seen. Clinical characteristics, treatment strategies, and prognosis remain elusive.

Methods: A 58-year-old Chinese woman with a 3-year history of intermittent headache and new development of polydipsia, polyuria, and binocular visual acuity decline over the past 4 months was admitted to our hospital. On admission, endocrine results were normal. Ophthalmic testing showed bitemporal visual field deficits and decreased visual acuity of both eyes. Pituitary dynamic magnetic resonance imaging showed a cystic sellar lesion measuring 5.6 × 5.2 × 6.2 mm with tumor shrinkage compared with initial neuroimaging. Transsphenoidal surgery was performed for tumor resection. An additional biopsy of the anterior pituitary lobe was performed because of intraoperative abnormal appearances of the pituitary gland. Pathology examinations revealed the specimen of the cystic lesion to be RCC and exhibited infiltration of massive lymphocytes, diffused plasmocytes, and eosinophils that were diagnostic of lymphocytic hypophysitis in the anterior pituitary lobe. During follow-up, the lesion of lymphocytic hypophysitis showed spontaneous shrinkage in the absence of steroid treatment after RCC resection. Final diagnosis was lymphocytic hypophysitis secondary to ruptured RCC.

Conclusions: We present a rare case of lymphocytic hypophysitis secondary to ruptured RCC and provide clinical data of such lesions in the literature. Full understanding of the clinical features plays an important role in diagnosis and treatment of lymphocytic hypophysitis secondary to ruptured RCC.