The coexistence of infundibular pituicytoma and Cushing’s disease due to pituitary adenoma: A case report

Abstract

Objectives. Pituicytomas are rare, solid, well-circumscribed, low grade (grade I), non-neuroendocrine, and noninfiltrative tumors of the neurohypophysis or infundibulum, which appear in the sellar/suprasellar regions. Herein, we present a case with Cushing’s disease (CD) caused by an ACTH-secreting pituitary adenoma in association with an infundibular pituicytoma.Subject and Results. A 37-year-old male patient presented to the hospital with a six-month history of blurry vision. Physical examination demonstrated plethora, excessive sweating, weight gain, moon facies, and acne. Basal serum cortisol and ACTH levels were 16 µg/dl and 32 pg/ml, respectively. The results of screening tests were suggestive of Cushing syndrome. It was also 1.97 µg/dl following 8 mg dexamethasone suppression test which was consistent with CD. Pituitary MR imaging revealed a single lesion measuring 6x6.5 mm on the pituitary stalk. Infundibular mass excision and pituitary exploration by extended endoscopic endonasal approach were applied. On immunohistochemistry, strong diffuse immunolabeling for both S100 and TTF-1 was noted for the cells of infundibular mass, diagnosed as pituicytoma. Because the developed panhypopituitarism postoperatively, patient was discharged with daily desmopressin, levothyroxine, hydrocortisone, and intramuscular testosterone, once a month.Conclusions. Pituicytoma is an uncommon noninvasive tumor of the sellar and suprasellar regions. In this case report, we described a patient with Cushing’s disease to whom MRI displayed only an infundibular well-circumscribed lesion, but not any pituitary adenoma. Despite the absence of any sellar lesion, awareness of other undetected possible lesion and exploring hypophysis during the transsphenoidal surgery is mandatory for the correct diagnosis.

A rare case of pituicytoma-related hypercortisolism in a patient with Cushing syndrome—case report

“…Pituicytomas present as a neoplasm of the sellar and suprasellar regions (World health organization grade 1), which arise from the neurohypophysis or infundibulum of the pituitary and its stalk, as in this case (Marco Del Pont et al 2019;Li et al 2019;Gezer et al 2019;Rumeh et al 2020). It is a rare tumor that can mimic pituitary adenoma and can be associated with Cushing's disease (Li et al 2019;Rumeh et al 2020).…”

“…The former is a tumor from the cells of the anterior endocrine lobe of the gland with three main pathways of adenohypophyseal cell differentiation for hormone production: corticotrophs, somatotrophs, mammosoamtotrophs, thryotrophs, and gonadotrophs (Cheng et al 2021b). The World Health Organization requires immunohistochemical staining for hormones produced by these cells in diagnosis (Feng et al 2018;Gezer et al 2019). According to the American Cancer Society, about 10,000 pituitary tumors are diagnosed annually in the USA, most of which are benign (Cheng et al 2021b).…”

“…This is supported by the absence of evidence of adenoma in pathology. Only few other such cases have been reported in the literature (Schmalisch et al 2010;Guo et al 2016;Marco Del Pont et al 2019;Li et al 2019;Feng et al 2018;Gezer et al 2019;Rumeh et al 2020;Barresi et al 2017;Cambiaso et al 2015;Chakraborti et al 2013;Yang et al 2016;Cheng et al 2021a). In other cases reported in the literature, all adult patients achieved remission of their Cushing disease with surgical dissection of the tumor, as was done for this case.…”

Pituicytoma Associated with Suspected Cushing’s Disease: Two Case Reports and a Literature Review

“…Some endocrine alterations, such as anterior pituitary hormone deficit, mild hyperprolactinemia, and diabetes insipidus, can be explained by the mass effect or stalk effect of posterior pituitary tumors (PPTs) [ 2 , 3 ]. However, remarkable pituitary hyperfunction disorders, mostly Cushing’s disease (CD), have also been reported in 17 patients [ 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 ], most of whom had a suspected diagnosis of pituitary adenoma before surgery. In patients presenting with biochemical CD, concurrent adrenocorticotropin (ACTH)-secreting adenoma or hyperplasia was occasionally evidenced in histopathological examinations [ 4 , 7 , 9 , 14 , 15 ], but mostly, only pituicytoma was identified.…”

Posterior pituitary tumours: patient outcomes and determinants of disease recurrence or persistence

“…Their most common mode of presentation is with mass effects and/or deficiency of anterior pituitary hormones ( 4 ). Rarely, they can be associated with anterior pituitary hyperfunction (acromegaly or Cushing’s syndrome) ( 5 , 6 , 7 ); however, posterior pituitary dysfunction (diabetes insipidus (DI)) is virtually never seen prior to surgery ( 4 ). PPTs are usually seen as suprasellar or sellar-suprasellar masses with no pathognomonic radiologic features ( 4 , 8 ) except the rarely reported early intense contrast enhancement (’Hasiloglu’s sign’) or the presence of proteinaceous material appearing as a T1-hypointensity on MRI (’star crack sign’) ( 9 , 10 ).…”