Collision sellar lesions: coexistence of pituitary adenoma and Rathke cleft cyst-a single-center experience

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

Collision tumors involving the sella are rare. Intrasellar collision tumors are most commonly composed of a combination of pituitary adenomas and pituitary neuroendocrine tumors; however, collision tumors consisting of a pituitary adenoma and intrasellar meningioma are exceedingly rare. The authors present the case of a 47-year-old man who presented with progressive right eye vision loss. Magnetic resonance imaging showed a large, heterogeneously enhancing sellar mass with suprasellar extension. Using a transcranial approach with a right subfrontal craniotomy, near-total resection of the mass was achieved. Histologic analysis confirmed a diagnosis of a gonadotroph adenoma with concomitant clear cell meningioma (CCM). This patient was discharged with improvement in visual acuity and no signs of diabetes insipidus. Given the indistinguishable radiographic characteristics of pituitary adenoma and CCM, a preoperative diagnosis of a collision tumor was difficult. This case was uniquely challenging since the CCM component lacked the classic dural attachment that is associated with meningiomas on neuroimaging. CCMs are classified as central nervous system (CNS) World Health Organization (WHO) grade 2 tumors and tend to behave more aggressively, therefore warranting close surveillance for signs of tumor recurrence. This is the first case to report a collision tumor consisting of pituitary adenoma and CCM.

Approach to the Patient: Differential Diagnosis of Cystic Sellar Lesions

Cystic lesions arising in the sellar region are not uncommon and encompass cystic pituitary adenomas, Rathke cleft cysts, craniopharyngiomas, and arachnoid cysts. Their clinical presentation may be similar, including headache, visual field defects, and anterior pituitary hormone deficits, which makes differential diagnosis challenging. On the other hand, imaging features may indicate certain pathologies. In this approach to the patient, we describe the case of a patient who presented with right temporal hemianopsia and a sellar/suprasellar cystic lesion, which was determined to be Rathke cleft cyst. We discuss the imaging characteristics that may suggest a particular diagnosis between Rathke cleft cyst, cystic pituitary adenoma, craniopharyngioma, and arachnoid cyst and propose a flowchart for aiding in the imaging differential diagnosis.

Primary collision tumors of the sellar region: Experience from a single center

Collision tumors are extremely rare in the sellar region, and their features have not been fully characterized. Here, we report our single-center experience in the diagnosis and management of these tumors, focusing primarily on their clinicopathological features. We first performed a retrospective study of pathological reports from patients who had undergone surgery for pituitary adenoma (PA) or craniopharyngioma (CP) at our hospital. Next, to identify collision tumors, patients with a second pathological diagnosis-such as Rathke's cleft cyst (RCC), gangliocytoma (GC), meningioma, or atypical teratoid/rhabdoid tumor (AT/RT)-were considered. Finally, the clinicopathological characteristics of these tumors were reviewed and analyzed. The results demonstrated that eleven of 2359 PA or CP cases (0.47 %) were found to exhibit sellar collision tumors; the patient cohort had a median age of 52 years (23-71) and was predominantly female (63.6 %, 7/11). In details, of the 2092 cases of PA, 10 were diagnosed with concurrent lesions (seven of RCC and one each of CP, meningioma, and GC). Of the 267 CP cases, a single patient presented with associated AT/RT. To our knowledge, this is the first reported adult case of this subtype. Notably, the preoperative CT and/or MRI of each patient revealed solely PA or CP. The endoscopic endonasal approach was the preferred surgery. In conclusion, the sellar collision tumors occur with low incidence, and the primary subtype is PA and RCC. Their definitive diagnosis depends primarily on pathological findings.

Coexistence of Pituitary Adenoma and Primary Pituitary Lymphoma: A Case Report and Review of the Literature

In the pituitary sella, the coexistence of pituitary adenoma and primary pituitary lymphoma is exceedingly rare. Thus far, only six cases have been reported. Here, we present the seventh case of coexisting pituitary adenoma and primary pituitary lymphoma, which was difficult to differentiate from other sellar tumors. To our knowledge, this is the first case of the prolactin subtype of the pituitary adenoma in literature. We have also systematically reviewed the literature and summarized the characteristics of coexisting pituitary adenoma and lymphoma. We believe this report provides a new clinical reference for the diagnosis and treatment of collision tumors of pituitary adenoma and lymphoma.

Current opinion on the diagnosis and management of non-functioning pituitary adenomas

INTRODUCTION

Non-functioning pituitary adenomas (NFPAs) are clinically silent tumors and the second most common pituitary adenoma. Surgery is the mainstay of treatment as there is, as yet, no effective medical treatment.

AREAS COVERED

We present current knowledge on the clinical diagnosis, histopathological classification, molecular data, and management strategies in NFPA.

EXPERT OPINION

NFPA is a heterogeneous group of tumors, in respect to their origin and clinical course. In recent years, research on pathology and molecular biology have advanced our knowledge of NFPA pathogenesis. NFPA exhibit, in the majority of cases, an indolent behavior, with satisfactory response to treatment. In aggressive cases, multimodal management is needed; however, even this approach may be insufficient, so the development of new treatments is warranted for better management. In this setting, the understanding of the mechanisms involved in the genesis and progression of NFPA is crucial for the identification and development of directed treatments with higher chances of response.

A Potential Concomitant Sellar Embryonic Remnant-Associated Collision Tumor: Systematic Review

BACKGROUND

Diagnosing the well-known concomitant Rathke's cleft cyst (RCC) and differentiating it from other sellar lesions are difficult because RCC is and other sellar lesions are closely related and represent a continuum from simple RCCs to more complex lesions. The purpose of this study is to better understand the adeno- and neurohypophysis adjacent to the par intermedia remnants and their role in the origin of the coexistence of these two distinct tumor neoplasias; to assess the incidence in different age groups; to categorize the pathohistological subtype, which can be incorporated in predictive/prognostic models; and finally, to evaluate the current evidence on collision tumors of the sellar embryonic remnant tract in terms of their biological behavior and pathology.

METHODS

Utilizing the PubMed database, data were collected from 1920 to 2019. Information about demographics, clinical characteristics, and age was summarized and analyzed by using univariable and multivariable models. The same cell type was observed regardless of whether the tumor was only one type or mixed types, and their histologic patterns were assessed.

RESULTS

The incidence rates were similar among patients stratified into three age subgroups: 40-49 years (24.57%), 50-59 years (19.54%), and older than 60 years (22.98%). We found that various types of sellar lesions, namely, squamous metaplasia (SM) + goblet cells (GC) (HR 46.326), foamy macrophages (FM) (HR 39.625), epithelial cells and multinucleated giant cells or cholesterin (EM) (HR 13.195), a cavernous portion of the right internal carotid artery (CP-ICA) (HR 9.427), epithelial cells with ciliated cuboidal (EC-CC) (HR 8.456), were independently associated with RCC pathological status. These divergent AUCs (0.848 for Hypo as RCC, 0.981 for RCC co PA, 0.926 for CD and CP co RCC) and subtypes of PA (HR 4.415, HR 2.286), Hypo (HR 3.310), CD and CP (HR 2.467), EC and DC and PG and SGR (HR 1.068), coexisting with the risk of a comorbid RCC lesion, may reflect the etiologic heterogeneity of coderivation and the different effects of some risk factors on tumor subtypes. Our analyses suggested that the greatest accuracy was observed for the pituitary adenoma subtype, with an AUC of 0.981 (95% confidence interval [CI]: 0.959-1.005), while the poorest accuracy was observed for aneurysms, with an AUC of 0.531 (95% CI: 0.104-0.958). We separately analyzed and confirmed the above results. Sensitivity analysis revealed no evidence of systematic bias due to missing data.

CONCLUSION

This study showed that the histopathological changes in patients with sellar embryonic remnant-associated collision tumors showed highly consistent epithelial cell replacement (renewal) (ciliated columnar epithelium to ciliated squamous epithelium to squamous epithelium) or accumulation, and the RCC cyst wall was similar in structure to the tracheobronchial airway epithelium, with progenitor cell characteristics. The collision accuracy between RCC and other tumors (PAs, craniopharyngioma, chordoma, etc.) is different; these characteristics constitute the theoretical basis for the postmigration development of the pharyngeal bursa.

Telomerase expression in clinically non-functioning pituitary adenomas

PURPOSE

Non-functioning pituitary adenomas (NFPA) are benign tumors, however, some are agressive. We aimed to assess if human telomerase reverse transcriptase (hTERT) is present in NFPA and if it can be used as a marker of aggressiveness and proliferation.

METHODS

Consecutive patients operated for NFPA whose fresh frozen tumors were available were included. We analyzed tumor's aggressiveness (based on radiological progression) and proliferation (based on Ki-67), as well as hTERT mRNA by quantitative real-time polymerase chain reaction (RT-qPCR).

RESULTS

We included 109 samples from 86 patients followed for a median period of 60 months (5-120 months). Aggressive tumors were present in 66% cases and proliferative tumors in 47.7%. Seven (6.4%) samples expressed hTERT: 3 (42.8%) had aggressive and proliferative tumors, 2 (28.6%) only exhibited aggressiveness and the remaining 2 (28.6%) only proliferation. From the aggressive and proliferative tumors, 14% and 16%, respectively, expressed hTERT. From the non-aggressive and non-proliferative tumors, 9% and 6%, respectively, expressed hTERT.

CONCLUSION

hTERT expression is present in a minority of NFPA and does not seem to be related to aggressiveness or proliferation in NFPA.

Cyclin A in nonfunctioning pituitary adenomas

PURPOSE

Assess cyclin A in nonfunctioning pituitary adenomas (NFPA) and compare its expression in non-invasive and non-proliferative tumors with invasive and proliferative tumors (12× higher risk of recurrence).

METHODS

Quantitative real time polymerase chain reaction to analyze cyclin A using normal pituitary gland as reference. Fold change (FC) > 1 was considered as increased. Tumor invasion was based on Knosp criteria (grades 3-4 considered invasive) and proliferation on the presence of at least two of three criteria: Ki-67 ≥ 3%; mitoses > 2/10; positive p53. Both groups were compared with Mann-Whitney test considering p value < 0.05 as statistically significant.

RESULTS

Thirty-one patients with NFPA were included. Tumors were mainly of gonadotrophic origin (74.2%), followed by corticotrophic (19.4%) and lactotrophic (3.2%) origins and null-cell adenomas (3.2%). Median tumor diameter was 3.5 cm (1.8-8.0) and Ki-67 was 3.0% (0.3-11%). Sixteen patients had tumors classified as non-invasive and non-proliferative and 15 as invasive and proliferative. Median FC was 0.31 in all tumors (0.13-1.94). Cyclin A was not related to invasion or proliferation (FC 0.41 in non-invasive and non-proliferative tumors and FC 0.30 in invasive and proliferative tumors; p = 0.968). Four (12.9%) patients had tumors that exhibited increased cyclin A [median FC of 1.04 (1.02-1.94)]-three of gonadotrophic origin and one null-cell adenoma, with two tumors classified as non-invasive and non-proliferative and two tumors classified as invasive and proliferative. Median tumor diameter in these samples was 3.4 cm (2.4-3.6) and Ki-67 was 5.1% (2-11%).

CONCLUSIONS

Cyclin A was increased in a minority of NFPA and does not seem to be related to invasion or proliferation.

Cushing's Syndrome in a Patient With Rathke's Cleft Cyst and ACTH Cell Hyperplasia Detected by 11C-Methionine PET Imaging-A Case Presentation

Background: Adrenocorticotropic Hormone (ACTH)-dependent Cushing's Syndrome (CS) is most often caused by a pituitary adenoma. Although rarely, it can also result from pituitary corticotroph cell hyperplasia (CH). Reports on concomitant pituitary lesions including ACTH-producing adenomas and Rathke's cleft cysts (RCCs) have been published. Positron emission tomography (PET), using ¹¹C-labelled-methionine (MET) as a tracer and co-registered with magnetic resonance imaging (MRI) has been shown to be useful in the diagnosis of pituitary collision lesions, however, its role is still under investigation. In this work we present the case of a patient in whom CS was caused by non-adenomatous CH within the wall of an RCC. Case Summary: In 2015 a patient with signs and symptoms of CS was referred to our Department. Biochemical studies repeatedly showed elevated midnight serum cortisol and ACTH levels. Magnetic resonance imaging of the sellar region revealed an RCC and MET-PET/MR showed heterogeneous labelled-methionine metabolism in the vicinity of the cyst's wall. Transsphenoidal surgery resulted in rapid, complete and lasting relief of symptoms. Histopathological examination demonstrated an RCC and CH. Conclusions: Concomitance of pituitary focal lesions is a rare phenomenon. Methionine-labelled PET/MR may be useful in the diagnosis of collision sellar lesions, including CH. Corticotroph cell hyperplasia can present as mild and fluctuating hypercortisolaemia.