Clival Ectopic Pituitary Adenoma Mimicking a Chordoma: Case Report and Review of the Literature

Ectopic Pituitary Neuroendocrine Tumors/Adenomas Around the Sella Turcica

Functional or non-secretory ectopic pituitary neuroendocrine tumors (PitNET) can form around the sella turcica during the development of the adenohypophysis by differentiating and detaching from the pharyngeal roof. These tumors usually appear in the sphenoid sinus, clivus, cavernous sinus, infundibulum, and suprasellar cistern. Ectopic PitNETs typically display the characteristic magnetic resonance imaging findings of pituitary adenomas. However, preoperative diagnosis of PitNETs is usually challenging because of the variety of clinical and imaging presentations, locations, and sizes. Ectopic suprasellar PitNETs resemble mass lesions in the pituitary stalk. Ectopic cavernous sinus of PitNETs are typically microadenomas in the medial wall. Ectopic sphenoclival tumors are characterized by more aggressive tumor activity than the other ectopic PitNETs. Although ectopic PitNETs are exceedingly rare, they should be considered as a differential diagnosis for masses around the sella turcica. Treatment of the disease should be individualized and may include medical care, surgical resection, gamma-knife radiosurgery, and radiotherapy.

Null-Cell Ectopic Pituitary Adenoma of the Nasal Cavity

An ectopic pituitary adenoma (EPA) is an uncommon type of pituitary adenoma, accounting for only 2% of all pituitary adenomas. EPAs are benign tumors that can occur anywhere along the migratory embryonic path of the pituitary gland and have no relationship to intrasellar elements. They are usually hormonally active and have a minor female predominance. The clinical features of EPAs are highly dependent on its hormonal activity, anatomical location, and its local mass effect. Appropriate radiological imaging is essential for the evaluation of EPAs. Imaging investigations show a normal pituitary gland and sellar turcica, provide details on the size of the tumor, its margins, and extent, and help with surgical planning. The criteria for diagnosing an ectopic pituitary adenoma depend on detailed histopathological examination. EPA management should be individualized. We present a case of a 71-year-old male who presented with a 9-month history of left nasal obstruction, purulent nasal discharge, and intermittent anterior epistaxis. The patient was being managed by his general practitioner for chronic rhinosinusitis but failure of his symptoms to resolve prompted a visit to the otorhinolaryngologist. The patient was diagnosed with a null-cell ectopic pituitary adenoma through histological analysis of a biopsy specimen that showed adenohypophyseal cells without cell-type-specific differentiation. The patient subsequently underwent an endoscopic endonasal excision and had an uneventful hospital stay.

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

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.

Clinical and radiological presentation of parasellar ectopic pituitary adenomas: case series and systematic review of the literature

PURPOSE

Parasellar ectopic pituitary adenomas (pEPAs) are extremely rare tumors located out of the sella turcica. PEPAs are heterogeneous entities in terms of anatomical localization and secretion of anterior pituitary hormones.

METHODS

Multicenter retrospective study. Clinical charts' consultation of patients diagnosed with parasellar lesions, to identify all subjects fulfilling the diagnostic criteria of parasellar EPAs. Systematic review of the literature focused on the medical management of prolactin-secreting pEPAs and on the prevalence of radiological bone invasion in pEPAs.

RESULTS

We identified four cases of pEPAs: (1) 54-year-old female with a prolactin-secreting suprasellar EPA successfully treated with cabergoline; (2) 74-year-old male with a non-functioning EPA of the sphenoidal sinus treated with endoscopic transsphenoidal surgery; (3) 75-year-old female with a giant lesion of the skull base (maximum diameter 7.2 cm) diagnosed as a non-functioning EPA after biopsy; (4) 49-year-old male with a silent corticotroph EPA of the sphenoidal sinus and clivus. Three out of four cases had radiological evidence of invasion of the surrounding bone structures. A systematic review of the literature highlighted that medical therapy can be effective in prolactin-secreting pEPAs. Overall, we found mention of local invasiveness in 65/147 cases (44.2%), confirmed by radiological signs of bone invasion/erosion.

CONCLUSION

Our experience confirms the heterogeneity of pEPAs in terms of clinical and radiological presentation, as well as hormone secretion. PEPAs show a high frequency of radiological bone invasion, though similar to that of sellar pituitary adenomas. Although extremely rare, pEPAs need to be considered in the differential diagnosis of parasellar lesions.

Ectopic Cavernous Sinus Microprolactinoma Treated Medically

Ectopic prolactin-secreting microadenomas are rare and management is often surgical in contrast to intrasellar pituitary prolactin-secreting microadenomas. We present a case of ectopic dopamine-resistant microprolactinoma treated with cabergoline which led to symptom resolution, hormonal remission, and cystic degeneration of the tumor. A 30-year-old active duty male presented with a chief complaint of inability to maintain an erection for 6 months. Initial workup revealed suppressed serum testosterone of 128.60 ng/ml with an elevated prolactin level at 275.10 ng/ml. Pituitary magnetic resonance imaging showed a small mass measuring 9 mm in the left cavernous sinus. Medical management was initiated with cabergoline, which was titrated over the course of a year from 0.5 mg a week to 3.5 mg a week at its peak before being weaned off completely at 54 months. After treatment, the patient's symptoms resolved, his prolactin decreased to 29.5 ng/ml, near-normal, and his tumor had decreased size with cystic degeneration. Management for any prolactinoma has three primary goals: remittance of symptoms, decrease in prolactin levels, and decrease in tumor size. These are achieved through primarily medical management or surgery. Even though ectopic microprolactinomas are still frequently addressed surgically, this case shows that medical therapy can successfully treat ectopic prolactin-secreting pituitary microadenomas even in cases of dopamine resistance.

Clival prolactinoma masquerading as a chordoma: a case report

Ectopic pituitary adenomas are a rare clinical entity and are frequently mistaken for other base of skull lesions on imaging. We report the clinical presentation and management of a woman presenting with an ectopic prolactinoma located in the clivus. A 66-year-old female presented with a 6-month history of headaches and light-headedness. Anatomical imaging demonstrated a clival lesion most suspicious for chordoma. Endocrinological assessment revealed modestly increased prolactin level with lower-than-expected gonadotrophins levels for her age. Surgical resection confirmed an ectopic prolactinoma. A skull base lesion in a patient with hormonal derangement should lend to a high clinical suspicion of an EPA as they may be treated with medications before surgery. Guidelines could assist clinicians investigating skull-based lesions to identify the rare, but important diagnosis of ectopic pituitary adenomas.

Ectopic pituitary adenomas: clinical features, diagnostic challenges and management

PURPOSE

Ectopic pituitary adenomas (EPAs) are extremely rare pituitary adenomas located outside the sella turcica without any connection with intrasellar components. This study aims to review all the reported cases to date and describe the clinical characteristics of EPAs.

METHODS

In a retrospective chart review, 14 patients were identified with EPAs in our hospital. A literature review was performed, and 166 cases in the literature met the criteria. Clinical data were analyzed.

RESULTS

Of 180 patients with EPAs, the mean age at diagnosis was 45.4 years, and 66.5% of the patients were females. EPAs were mainly located in the sphenoid sinus (34.4%) and suprasellar region (25.6%), followed by the clivus (15.6%), cavernous sinus (13.3%) and nasopharynx (5.6%). Adrenocorticotropic hormone (ACTH)-secreting (38.9%) and nonfunctioning (27.2%) adenomas were predominant. Patients with suprasellar EPAs were more likely to present menstrual disorders and visual changes, while patients with clival EPAs were more likely to suffer from headaches. EPAs in the cavernous sinus and suprasellar space were more likely to be initially misdiagnosed as a suspicious intrasellar mass on imaging examination. The complete tumor resection rates for EPAs in the sphenoid sinus, suprasellar region, clivus, cavernous sinus and nasopharynx were 72.3%, 88.6%, 45.0%, 73.3% and 88.9%, respectively.

CONCLUSIONS

EPA clinical characteristics varied across different tumor locations and hormone-secreting types. In addition to comprehensive hormone evaluation and careful review of imaging data, nuclear medicine and surgical biopsy should also be considered when facing differential difficulty. EPA management should be individualized.

Ectopic hyperprolactinaemia due to a malignant uterine tumor resembling ovarian sex cord tumors (UTROCST)

PURPOSE

Moderate hyperprolactinaemia (2-5 times upper limit of normal) occurring in a patient with a normal pituitary MRI is generally considered to be due to a lesion below the level of detection of the MRI scanner assuming macroprolactin and stress have been excluded. Most patients with mild-to-moderate hyperprolactinaemia and a normal MRI respond to dopamine agonist therapy. We present the rare case of a patient who had prolactin elevation typical of a prolactin-secreting pituitary macroadenoma,with a normal cranial MRI, and in whom the prolactin rose further with dopamine agonist treatment. Subsequent investigations revealed ectopic hyperprolactinaemia to a uterine tumor resembling ovarian sex cord tumor (UTROSCT) which resolved following tumor resection. Although mostly considered to be benign, the UTROSCT recurred with recurrent hyperprolactinaemia and intraabdominal metastases.

METHODS

We have systematically and critically reviewed existing literature relating to ectopic hyperprolactinaemia in general and UTROCST specifically.

RESULTS

Fewer than 80 cases of UTROSCTs have been reported globally of which about 23% have shown malignant behaviour. There are fewer than 10 cases of paraneoplastic hyperprolactinaemia originating from uterine neoplasms including one other case of ectopic hyperprolactinaemia to a UTROSCT.

CONCLUSIONS

Our case demonstrates the importance of screening for extracranial hyperprolactinaemia in the context of: (1) substantially raised prolactin (10× ULN) and (2) normal cranial MRI assuming macroprolactin has been excluded. The majority of extracranial ectopic prolactin-secreting tumors occur in the reproductive organs.

Ectopic GH-secreting pituitary adenoma of the clivus: systematic literature review of a challenging tumour

PURPOSE

Acromegaly is usually due to growth hormone (GH)-secreting pituitary adenomas, but it may be exceptionally caused by GH-secreting ectopic pituitary adenomas (EPA). EPA are defined as extra-sellar pituitary tumours, extra- or intra-cranially sited, entirely separated from the pituitary stalk and gland. The aim of the study is to address the challenges in the management of clival GHEPA.

METHODS

We reported a case of a 53-year-old acromegalic patient with a primary clival GHEPA and reviewed systematically the relevant English literature between 1975 and 2019, in keeping with the PRISMA guidelines.

RESULTS

Four cases of primary clival GHEPA have been described in literature apart from ours. All patients presented with acromegalic features, elevated circulating GH and/or insulin-like growth factor-1 levels. Hyperprolactinemia and empty sella were described in two cases, respectively. These tumours show the typical imaging characteristics of pituitary adenomas, but their neuroradiological diagnosis may be challenging due to their sizes and the difficulty in defining the absence of connections with the pituitary fossa.

CONCLUSION

Although primary clival GHEPA are exceedingly rare, even if likely under-reported in literature, they should be considered in the differential diagnosis of clival tumours because of their specific management. Surgery represents the first-line treatment option, while medical and radiation therapies can be adopted as neo-adjuvant, adjuvant or primary treatments according to tumour and patient characteristics.

Ectopic pituitary adenomas: common presentations of a rare entity

PURPOSE

Ectopic pituitary adenomas (EPA) are rare tumors thought to arise from embryological remnants along the route of normal pituitary migration. Clinically, these tumors vary in hormonal activity and can exert mass effect based on location and size.

METHODS

We performed a single-center retrospective analysis of patients with diagnosis of ectopic pituitary adenoma from 2001 to 2018.

RESULTS

Five patients were identified with EPA: a 48-year-old woman with suprasellar EPA treated with transsphenoidal removal of the tumor, a 44-year-old woman with cavernous EPA treated with transsphenoidal removal of the tumor, a 48-year-old woman with sphenoid EPA treated with cabergoline, a 45-year-old man with clival EPA treated with cabergoline and transsphenoidal surgical resection, and a 54-year-old man with clival EPA treated with cabergoline therapy.

CONCLUSIONS

EPA should be considered as a differential diagnosis of juxta-sellar lesions. Appropriate hormonal testing may lead to early diagnosis, avoidance of unnecessary biopsy or surgery, and improved outcomes.

Clival Metastasis of Hepatocellular Carcinoma with an Initial Histopathological Diagnosis of Atypical Pituitary Adenoma

Histologically, hepatocellular carcinoma (HCC) and atypical pituitary adenoma are similar, posing a potential clinical problem. A 76-year-old woman, whose past medical history was significant for hepatitis C virus (HCV), positivity without liver cirrhosis was presented with abducens nerve (CN VI) palsy. Contrast-enhanced magnetic resonance imaging (MRI) showed a clival tumor with infiltration of the right cavernous sinus. Subtotal resection was performed using a right anterior petrosal approach. Histological diagnosis was pituitary adenoma. Thirty-four days after the operation, MRI imaging showed residual tumor growth without any liver masses on computed tomography (CT). The patient underwent a second operation using an endoscopic transnasal transsphenoidal approach. Histological examination of the specimen gave a positive reaction for α -fetoprotein. Repeat whole-body CT showed an enhanced liver mass. Based on these findings, the lesion was diagnosed as metastatic HCC. The patient died of liver failure 6 months later. In this case, tumor diagnosis was difficult because of the histological similarity of HCC and pituitary adenoma, and the fact that the clival tumor grew prior to presentation of the liver mass on CT. This case emphasizes the importance of comparing the pathological diagnosis with the patient's clinical course.

The identification of H3F3A mutation in giant cell tumour of the clivus and the histological diagnostic algorithm of other clival lesions permit the differential diagnosis in this location

BACKGROUND

Giant Cell Tumour of Bone (GCT) is a locally aggressive primary bone tumour that usually occurs at the epiphyses of the long bones of the appendicular skeleton with a tendency to recurrence. Recurrent somatic H3F3A mutations have been described in 92% of GCT cases. GCTs involving the Clivus are extremely rare lesions and less than 15 cases are described in the literature. They represent a surgery challenge and are easily misdiagnosed. Our aim was to reveal if the genetic bases underlying Clival GCTs were the same of GCTs of long bones to improve the diagnosis and treatment.

METHODS

The targeted somatic sequencing of GCT-related genes (H3F3A, H3F3B, IDH1, IDH2 and ZNF687) was performed on Clival GCT biopsies of two different cases. Histological analyses on the same tissues were used to detect the neoplastic population and its expression profile.

RESULTS

Sanger sequencing revealed that both patients were positive for the p.Gly34Trp mutation in the H3F3A gene. Immunofluorescence assay using monoclonal antibody, specifically detecting the mutant H3.3, highlighted that the mutation only involved the mononuclear cell population and not the multinucleated giant cells. Moreover, immunohistochemistry assay showed that RANKL was highly expressed by the stromal cells within Clival GCT, mimicking what happens in GCT of the long bones. In addition, systematic literature review allowed us to generate a histology-based diagnostic algorithm of the most common clival lesions.

CONCLUSIONS

We conclude that the Clival GCT is genetically defined by somatic mutation in the H3F3A gene, linking it to the GCT of long bones. The similarity with GCTs of long bones let us to hypothesize the utility of Denosumab therapy (already effective for GCTs) in these surgically challenging cases. Moreover, H3F3A genetic screening can be combined to the histological analysis to differentiate GCTs from morphologically similar giant cell-rich sarcomas, while the histological diagnostic algorithm could help the differential diagnosis of other clival lesions.