Isolated Pituitary Stalk Duplication in an Asymptomatic Adult Woman: A Case Report and Review of the Literature

Carvallo MS, Duarte EHF, De Sousa IAS, Tischer V, Santos AS and Violante AHD

Published on: 2025-07-24

Abstract

Introduction

Pituitary stalk duplication (PSD) is a rare congenital anomaly often associated with midline defects and pituitary gland duplication. Isolated PSD, an even rarer occurrence, presents a significant diagnostic challenge, particularly in its differentiation from metastatic sellar lesions. Here, we report a unique case of isolated PSD with initial diagnosis as a metastatic lesion in a patient with human epidermal growth factor receptor2(HER2)-positive             breast cancer.

Case Presentation

A 64-year-old woman with a history of HER2-positive breast cancer presented with a sellar lesion identified on brain magnetic resonance imaging (MRI), initially suspected to be a metastatic tumor. She reported symptoms of headache, insomnia, and hair loss but had no evidence of endocrine dysfunction. Subsequent imaging revealed pituitary stalk duplication without associated glandular abnormalities. A definitive diagnosis of isolated pituitary stalk duplication was made based on neuroradiological findings.

Conclusion

This case highlights the importance of considering PSD in the differential diagnosis of sellar lesions, particularly in patients with complex medical histories. Recognition through advanced imaging techniques is essential to avoid misdiagnosis and guide appropriate management.