Pituitary Metastasis of Breast Cancer: A Case Report and Literature Review

  Pituitary metastasis (PM) refers to a type of disease in which extracranial malignant tumors metastasize to the pituitary gland. It is extremely rare in clinical practice, with the incidence of PM accounting for only 0.14%-3.6% of all intracranial metastases of malignant tumors and only 1.0%-3.6% of all sellar tumors [2]. In patients with malignant tumors, the symptoms caused by pituitary metastasis are easily misunderstood as tumor cachexia. In addition, pituitary metastasis and primary pituitary tumors, symptoms of hypophysitis caused by other drugs, and imaging examinations often overlap or resemble each other, so the diagnosis of pituitary metastasis is often misdiagnosed or missed. We received a patient with breast cancer who underwent postoperative chemoradiotherapy and targeted therapy with the main symptoms of "nausea, vomiting, and hypernatremia". After observing the changes in the condition, completing various related auxiliary examinations and multidisciplinary consultations, the patient was finally diagnosed with "breast cancer pituitary metastasis and panpituitarism". This article discusses the diagnosis and treatment process and analyzes and discusses it in combination with relevant literature to deepen the understanding of pituitary metastasis, reduce missed diagnosis and misdiagnosis, and improve the diagnosis of such diseases.