2026 Poster Presentations
P044: ECTOPIC CORTICOTROPH PITUITARY ADENOMA OF CAVERNOUS SINUS WITH INVOLUTION AFTER BIOPSY: CASE REPORT AND LITERATURE REVIEW
Carlin Chuck, MD; Sohan Tarigopula; Alice Lin; Christine K Lee; Brown University
Objective: Ectopic pituitary adenomas are a rare entity of adenoma formation without direct involvement of the pituitary gland, and can often present diagnostic challenges. We describe a rare presentation of a patient presenting with left ophthalmoplegia and ptosis, found to have a lateral cavernous sinus mass extending towards V2/V3 with imaging characteristics concerning for malignancy. A transcranial resective biopsy of the tumor revealed a corticotroph pituitary adenoma, which subsequently underwent spontaneous involution and symptom resolution. We also review the presentation and characteristics of ectopic pituitary adenomas, and discuss the management of these tumors.
Methods: A rare case of ectopic corticotopic ectopic pituitary adenoma was described. We also conducted a literature review of ectopic pituitary adenoma, and analyzed the incidence, location of occurrence, resection rates, and postoperative outcomes.
Results: A 48-year-old female with past medical history of type 2 diabetes and obstructive sleep apnea presented with complaints of headaches, left eye ptosis, and blurry vision, and recent fatigue, fevers, and chills with flu-like symptoms. Exam was notable for dense left eye ptosis, mydriasis, and complete ophthalmoplegia. An MRI brain demonstrated masslike expansion of the left cavernous sinus with extension towards foramen spinosum and ovale, with a pituitary gland with normal size and shape (Figure 1A). Leading differential diagnoses included malignant primary or metastatic tumor. Hypercortisolemia was noted and considered secondary to acute stress response from influenza and pneumonia. A transcranial biopsy was performed of the extradural tumor extending along V2/V3, as well as partial resection of tumor in lateral cavernous sinus. Frozen pathology returned as a spindle cell tumor; however, final pathology returned as a corticotroph pituitary adenoma. Subsequently over the next six months, symptoms of ptosis and ophthalmoplegia resolved, cortisol normalized, and MRI imaging demonstrated involution and complete resolution of the tumor.
A literature review was conducted, and it was found that ectopic pituitary adenomas are a rare entity, and while the sphenoid sinus is the most common location (30-50%) of these, the minority (~13% in meta-analysis) are within the cavernous sinus. The majority (60-70%) of ectopic pituitary adenomas are functional. Resection rates vary from 45-89%. In the previous literature, radiotherapy was commonly employed for subtotal resection. Recurrence rates were not consistently reported. There were no previous case reports of involution after subtotal resection or biopsy, highlighting the rarity of this phenomenon.
Conclusions: We demonstrate a rare presentation of ectopic pituitary adenoma in which a resective biopsy precipitated a spontaneous involution, leading to resolution of the tumor and preoperative symptoms. This case highlights a diagnostic challenge in the broad differential for lateral cavernous sinus masses. We advocate for an initial postoperative period of close monitoring of ectopic pituitary adenoma even after subtotal resection, rather than immediately initiating radiation or medical treatment, as involution of the residual mass can obviate the need for additional treatment.
Figure 1: MRI T1 sequence with gadolinium demonstrating a heterogeneously enhancing lateral left cavernous sinus mass with extension along V2 and V3. A: Preoperative imaging. B: Postoperative imaging. C: Two months postop
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