An Incidental Collision Tumor of the Sella Turcica

Abstract

Objective: To present a case describing an incidentally discovered pituitary mass that was found to be a collision tumor containing 2 distinct histologic cell types: (1) a growth hormone (GH)-secreting pituitary adenoma, and (2) a gangliocytoma. Methods: Sellar gangliocytomas are very rare benign neuroblastic tumors that originate from the posterior pituitary. The majority are associated with pituitary adenomas. The coexistence of these 2 morphologically distinct tumors is known as a collision tumor, a rare disease entity of which the pathogenesis is not well understood. We present a case of a woman with an incidentally discovered pituitary mass that was found to be a collision tumor. Results: A 44-year-old woman presented with an incidentally discovered pituitary mass and was found to have elevated insulin-like growth factor 1 (IGF-1) levels. The patient underwent endoscopic transsphenoidal excision of the pituitary mass. Histopathology of the tumor revealed a mixed pituitary adenoma that stained for GH and prolactin, and a gangliocytoma. Postoperatively, the patient developed temporary central adrenal insufficiency and permanent diabetes insipidus. Postoperative lab studies revealed a normal IGF-1 level, and a magnetic resonance imaging scan showed no residual or recurrent tumor. Conclusion: While sellar gangliocytoma is a rare lesion, when it is present, a co-existing pituitary adenoma should also be suspected. Further investigation should be done to determine the pathophysiology of these collision tumors, which could be beneficial in guiding diagnosis and treatment. (AACE Clinical Case Rep. 2019;5:e247-e249) Abbreviations: GH = growth hormone; IGF-1 = insulin-like growth factor 1; PRL = prolactin e248 Collision Tumor of the Sella, AACE Clinical Case Rep. 2019;5(No. 4)

Pituitary Adenoma Coexistent with Sellar Clear Cell Meningioma Unattached to the Dura: Case Report and Treatment Considerations

“…Secondary tumors that have been described as co-occurring with pituitary adenomas include gangliocytomas, pilocytic astrocytomas, craniopharyngiomas, spindle cell astrocytomas, pituicytomas, granular cell tumors, and Rathke's cleft cysts. 19 20 21 25 Collision tumors consisting of a pituitary adenoma and parasellar meningioma are exceedingly rare. There are several case reports and series describing the coexistence of a pituitary adenoma and sellar/suprasellar meningioma, although none have reported a specific diagnosis of clear cell meningioma.…”

“…A literature review was conducted using PubMed to identify available case reports and case series on collision tumors occurring in the sellar or suprasellar region of the brain from 1986 to 2022, linking “collision tumor” and “sella” or “suprasellar” or “parasellar” or “pituitary.” The search regarding clear cell meningioma utilized the search terms “clear cell meningioma” and “without dural attachment.” After independent evaluation for content and relevance, we identified a total of 30 articles published from the years 1986 to 2022 that describe collision tumors comprising PitNETs and various co-occurring tumors, and 6 articles published from 2009 to 2021 describing the diagnosis of clear cell meningioma without a dural attachment. The results of this literature review are shown in Tables 1 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 and 2 . 31 32 33 34 35 36 37 …”