2025 Poster Presentations
P305: PERSISTENT CENTRAL HYPERCORTISOLEMIA FOLLOWING PITUITARY STALK TUMOR RESECTION: CASE LESSON
Patrick Toyota, MD; Kristen Marciniuk, MD, PhD; Devon Houdek, MD; Neil Arnstead, MD; Amit R Persad, MD; Luke Hnenny, MD; University of Saskatchewan
Background: Pituitary stalk lesions are rare entities with variable clinical manifestations. Their detection during work-up for endocrinologic abnormalities represents a decision-making challenge. We present the case of a 57-year-old female with central ACTH-dependent hypercortisolemia who was discovered to have a pituitary stalk lesion, which we decided to treat surgically.
Case Description: A 57-year-old female was referred to endocrinology for management of her diabetes. She had a Cushingoid appearance and underwent subsequent workup which demonstrated evidence of ACTH-dependent central Cushing's Syndrome (Morning cortisol > 500 nmol/L; Cortisol post-low dose suppression 792 nmol/L; cortisol post-high dose suppression test 324 nmol/L). Imaging demonstrated a 4.7mm nodule originating from the pituitary infundibulum.
Management: Inferior petrosal sinus sampling and PET-CT was considered, however, given the cortisol suppression seen on HDDST, presence of stalk lesion, and absence of any gland lesion on imaging, glandular pituitary and extracranial ectopic sources were thought to be unlikely. We elected to proceed with endoscopic endonasal approach with extended transtubercular exposure for resection of the infundibular lesion with goal of biochemical cure.
Outcome: A satisfactory technical and radiographic resection of the infundibular lesion was achieved. However, the patient's hypercortisolemia failed to resolve. Histopathologic analysis identified the lesion as a granulocytoma. Subsequent inferior petrosal sinus sampling further demonstrated evidence of ACTH-dependent central Cushing's syndrome. The patient has since been referred for consideration of bilateral adrenalectomy for management of her persistent hypercortisolemia with no clear neurosurgical target.
Conclusion: Our case demonstrates a complex clinical picture in which our patient presented with biochemical results suggestive of central ACTH-dependent hypercortisolemia; however no glandular lesion identified on imaging. The presence of an infundibular lesion led to subsequent surgical intervention which unfortunately did not result in biochemical cure despite adequate technical results. The authors believe this case illustrates a challenging clinical conundrum which emphasizes the uncertainty that should be associated with management of pituitary stalk lesions.
