Ectopic invasive ACTH-secreting pituitary adenoma mimicking chordoma: a case report and literature review

Abstract

Background Ectopic pituitary adenoma (EPA) is defined as a special type of pituitary adenoma that originates outside of the sellar region, is extra- or intra-cranially located, and without connection to normal pituitary tissue. EPA is extremely rare, with most cases presented as case reports or small case series. Due to nonspecific symptoms and laboratory indicators, the preoperative diagnosis, treatment and management for EPA remain challenging. Case presentation Here, we report the imaging phenotype and pathological findings of a case of invasive EPA in a 47-year-old woman. A preoperative non-contrast CT scan revealed a 5.8 × 3.6 × 3.7 cm soft tissue mass located in the sphenoid sinus and clivus. MRI showed an ill-defined solid mass with heterogeneous signals on T1-weighted and T2-weighted images. The mass displayed infiltrative growth pattern, destroying bone of the skull base, invading adjacent muscles and encasing vessels. The patient underwent partial tumor resection via transsphenoidal endoscopic surgery. Pathological examination led to diagnosis of ectopic ACTH-secreting pituitary adenoma. Post-surgery, the patient received external beam radiotherapy. Conclusion EPA with invasive growth pattern has rarely been reported. The imaging phenotype displays its relationship to the pituitary tissue and surrounding structures. Immunohistochemical examination acts as a crucial role in differentiating EPA from other skull base tumors. This case report adds to the literature on EPA by summarizing its characteristics alongside a review of the literature.

Ectopic Sphenoid Sinus Prolactinoma Associated With Empty Sella and Recurrent Meningitis Treated Successfully With Cabergoline

“…EPAs are extremely rare tumors, with only approximately 100 cases reported in the English literature [ 5 ]. By definition, they are extrasellar pituitary adenomas that demonstrate no connection to the pituitary gland.…”

Cushing syndrome caused by an ectopic ACTH-producing pituitary adenoma of the clivus region: A rare case report and literature review

“…NA ACTH ACTH Transsphenoidal surgery, GTR No 18 Symptomatic relief Shah et al 2011 [13] 64 Li et al 2023 [15] 47 chromatin, and visible nucleoli (Fig. 2B).…”

“…[8] It has been reported that ectopic ACTH-producing pituitary adenoma (EAPA) can occur in the sphenoid sinus, cavernous sinus, clivus, and suprasellar region, [9] with EAPA in the clivus region being extremely rare, and merely 6 cases have been reported in the English literature (Table 1). [10][11][12][13][14][15] Furthermore, as summarized in the Table 1, EAPA in the clivus area has unique symptoms, which may lead to misdiagnosis as well as delay in treatment. Therefore, we herein described a case of CS from an EAPA of the clivus region and reviewed relevant literature for the purpose of further understanding this extraordinarily unusual condition.…”

Ectopic Pituitary Neuroendocrine Tumors/Adenomas Around the Sella Turcica

“…In some cases, the invading muscles and encasing vessels identified can also be considered within the aggressiveness criteria. 40 …”