Clinically Silent Adrenocorticotropic Hormone-Positive Crooke Cell Adenoma: Case Report and Review of Literature

Crooke Cell Adenoma Confers Poorer Endocrinological Outcomes Compared with Corticotroph Adenoma: Results of a Multicenter, International Analysis

BACKGROUND

Crooke cell adenomas (CCAs) are a rare, aggressive subset of secretory pituitary corticotroph adenomas (sCTAs) found in 5%-10% of patients with Cushing disease. Multiple studies support worse outcomes in CCAs but are limited by small sample size and single-institution databases. We compared outcomes in CCA and sCTA using a multicenter, international retrospective database of high-volume skull base centers.

METHODS

Patients surgically treated for pituitary adenoma from January 2017 through December 2020 were included.

RESULTS

Among 2826 patients from 12 international centers, 20 patients with CCA and 480 patients with sCTA were identified. No difference in baseline demographics, tumor characteristics, or postoperative complications was seen. Microsurgical approaches (60% CCA vs. 62.3% sCTA) were most common. Gross total resection was higher in CCA patients (100% vs. 83%, P = 0.05). Among patients with gross total resection according to intraoperative findings, fewer CCA patients had postoperative hormone normalization of pituitary function (50% vs. 77.8%, P < 0.01) and remission of hypersecretion by 3-6 months (75% vs. 84.3%, P < 0.01). This was the case despite CCA having better local control rates (100% vs. 96%, P < 0.01) and fewer patients with remnant on magnetic resonance imaging (0% vs. 7.2%, P < 0.01). A systematic literature review of 35 studies reporting on various treatment strategies reiterated the high rate of residual tumor, persistent hypercortisolism, and tumor-related mortality in CCA patients.

CONCLUSIONS

This modern, multicenter series of patients with CCA reflects their poor prognosis and reduced postsurgical hormonal normalization. Further work is necessary to better understand the pathophysiology of CCA to devise more targeted treatment approaches.

Pathology of Crooke Cells in the Human Pituitaries: A Timely Review

Crooke cell change was first found in the regressed and suppressed corticotroph (adrenocorticotropic hormone-producing) cells, and now is known to occur in pituitary tumors. The tumor cells of this type can be recognized by morphology with immunohistochemistry, and are well known to predict aggressive behavior such as invasion and rare metastases. This is one of the representative neuroendocrine tumors in the pituitary which is now considered to have malignant potential as proposed in the pancreas and gastrointestinal tracts. It is important to emphasize the pituitary tumor pathology such as Crooke cell change for prognostication and appropriate therapies. This review article describes the evolution from the Crooke cells to Crooke cell tumors which is timely along with the Fifth WHO classification 2022 published online.

Functioning Crooke Cell Adenomas: Case Series and Literature Review

BACKGROUND

Crooke cell adenomas (CCA) are rare potentially aggressive pituitary adenomas. Data regarding prevalence and clinical course is sparse.

METHODS

Methods consisted of a retrospective review of 59 consecutive functioning corticotroph adenomas (FCA) operated between October 2017-November 2020, and a literature review of CCA publications since 1991.

RESULTS

The prevalence of CCA among FCA at our institution was 8.5% (5/59). In the 4 other surgical cases series, prevalence of CCA ranged between 0%-6.8%. Our patients, 4 women and 1 man, mean age 46±11 years, presented with hypercortisolism (3/5), vision loss (1/5) and incidentally (1/5). All patients had elevated ACTH (151±54 pg/ml) and urinary free cortisol (830±796.5 μg/day) levels. Radiologically, 3 tumors were macroadenomas and 2 had cavernous sinus invasion. All patients achieved biochemical remission at 3 months postoperatively. One patient with a giant pituitary adenoma underwent fractionated radiation for residual tumor. During follow-up (range: 3.1-31.0 months), no patients had evidence of radiological or biochemical recurrence. The literature review (3 case series) and 21 case reports identified 22 FCA with outcome data. Additional treatments included reoperation (50%), radiation (59%), bilateral adrenalectomy (23%) and Temozolomide (36%).

CONCLUSION

We report a higher CCA prevalence among functioning ACTH-adenomas after the implementation of 2017 WHO classification. In our series and the literature, most CCAs were macroadenomas with high ACTH levels. Postoperative outcomes were excellent in our series, while some cases from the literature were refractory to standard treatments. Larger clinical and molecular studies are needed to identify patients at risk.

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.

Neuropathology of Pituitary Adenomas and Sellar Lesions

The pituitary gland is the site of numerous neoplastic and inflammatory processes. The overwhelmingly most frequent tumors arise from cells of the anterior lobe, the pituitary neuroendocrine tumors (PitNETs). Immunohistochemistry assay staining for pituitary hormones is the core tool for classifying PitNETs, resulting in the diagnosis of somatotroph PitNETs, lactotroph PitNETs, and so on. For cases showing no hormonal expression, the updated WHO classification system now considers the assessment of several transcription factors: PIT-1 (pituitary-specific POU-class homeodomain transcription factor); T-PIT (T-box family member TBX19); and SF-1 (steroidogenic factor regulating gonadotroph cell differentiation) before rendering a diagnosis of null cell adenoma. Other tumors and disease processes of this site often mimic PitNETs radiographically and sometimes even clinically (ie, compression of the optic chiasm). These potpourri of processes include germ cell neoplasms (especially germinomas), tumors that originate from Rathke's pouch (craniopharyngiomas, Rathke's cleft cyst), tumors that originate from the posterior lobe of the pituitary (pituicytoma, spindle cell oncocytoma, granular cell tumor), and tumors that originate from the meninges (especially meningiomas). In addition to neoplasms, several described inflammatory and related conditions exist that need to be distinguished from PitNETs. These include lymphocytic hypophysitis and Langerhans cell histiocytosis, a neoplastic disorder of histiocytes. In this review, we aim to briefly describe the main pituitary and sellar lesions, with emphasis on the most common tumors, the PitNETs.

Apoplexy of Crooke cell tumour leading to the diagnosis of severe Cushing disease; a case report

BACKGROUND

Patients with Crooke cell tumours present with features of Cushing syndrome or mass effect. There are few reports of patients with Crooke cell tumours presenting due to apoplexy. All of them had silent tumours. Patients with Cushing syndrome caused by Crooke cell tumours have not been reported to present with apoplexy.

CASE PRESENTATION

A 35-year-old female presented with sudden onset headache and visual loss for 1 week. She had secondary amenorrhoea for 10 years. There were features of Cushing syndrome including central obesity, multiple monomorphic acne, dorso-cervical and supraclavicular fat pads, hypertension, proximal weakness, pigmentation and refractory hypokalaemia. She was found to have markedly elevated serum cortisol, central hypothyroidism and hypogonadotropic hypogonadism. There was a mass in the sellar region (4.7 cm × 1.9 cm × 5.3 cm) suggestive of a pituitary tumour extending to the suprasellar region. Imaging showed evidence of bleeding and compression of the optic chiasm. She underwent urgent trans-sphenoidal excision of the tumour. Histology was compatible with a pituitary neuroendocrine tumour. There was margination of ACTH reactivity to the cell periphery and ring like positivity in most of the cells in the cytokeratin stain. Features were in favour of a Crooke cell tumour. After surgery she improved gradually and became eucortisolaemic.

CONCLUSIONS

This is a unique presentation of an apoplexy of Crooke cell tumour causing Cushing syndrome. Delayed health seeking behaviour of this patient despite severe Cushing disease could have led to this presentation which has not been reported before.

Invasive Crooke cell adenoma in a patient with diffuse large B-cell lymphoma

Crooke cell adenoma (CCA) is an aggressive corticotroph subtype of pituitary adenoma often with cyclically elevated blood adrenocorticotropic hormone (ACTH), which preoperative diagnosis is challenging especially in the context of a functionally silent invasive tumor and a history of high-stage malignancy such as diffuse large B-cell lymphoma (DLBCL). Here, we report the first case of invasive CCA in a patient with DLBCL. A 71 year-old previously healthy man was recently diagnosed with DLBCL that was treated with CHOP-R chemotherapy. Within one week of completing his first cycle of chemotherapy, he had a frontal headache that progressed to right-sided proptosis. Cranial MRI showed a heterogeneously enhancing mass with invasion into the sellar and suprasellar compartment, compression of the optic chiasm, as well as extension into the clivus, bilateral cavernous sinuses, and the prepontine cistern. He underwent a partial resection for the pituitary tumor debulking. Pathological examination revealed CCA with invasion into the adjacent tissue. The patient had no history of Cushing disease or syndrome, but his blood ACTH was found to be elevated on the operation day. Our present case and literature review suggest that comorbidity of CCA or ACTH-producing adenoma and B-cell lymphoma deserves awareness in our clinical practice, as these two diseases and/or their therapies may interact substantially. CAA should be considered in the major differential diagnosis for an invasive sellar tumor, even without blood ACTH elevation and/or with a history of malignant lymphoma.

Predictive modeling for pituitary adenomas: single center experience in 501 consecutive patients

BACKGROUND

Personalized postoperative management of patients with pituitary adenomas requires an early risk stratification system.

METHODS

We reviewed 501 cases operated between 10/27/2011 and 5/5/2016 by a single neurosurgeon. We determined biochemical remission and tumor resection at 3 months, and biochemical recurrence, tumor recurrence, radiation and reoperation during follow-up. We considered age, gender, tumor diameter, cavernous sinus invasion (CSI) by MRI, diagnostic category (clinical, biochemical and immunohistochemical), and proliferation markers in a Cox proportional hazards model. We built predictive models with the significant parameters and used Kaplan-Meier survival curves for time-dependent analyses.

RESULTS

The 501 cases comprised 141 functional and 360 nonfunctional adenomas. Tumor diameter, CSI, and ki-67 index predicted long-term events. Model 1 (CSI, diameter ≥ 2.9 cm and ki-67 > 3%) identified 18 (3.6%) adenomas and predicted persistent hypersecretory syndrome and residual tumor with 98.7% specificity (OR 8.6; CI 3.0-24.7). Model 2 (ki-67 > 3% and CSI) identified 48 (9.6%) adenomas and had 93.1% specificity (OR 3.3; CI 1.8-6.0). Model 3 (ki-67 > 3%, mitoses and p53, former "atypical" adenoma) identified 26 (5.2%) adenomas and had 96.0% specificity (OR 2.3; CI 1.0-5.0). Model 1 best predicted the long-term event-free survival and was strengthened when Knosp 3-4 CSI grades were used. Model 2 better identified the smaller adenomas at risk. Among the WHO 2017 special PA subtypes, patients with silent corticotroph adenoma had a lower event-free survival than ACTH-negative nonfunctional adenomas.

CONCLUSION

Use of CSI, ki-67 and tumor diameter in prediction models facilitates tailored surveillance and management of patients with pituitary adenomas.