Recurrent pituitary ependymoma: a complex clinical problem

Preoperative Prediction of Non-functional Pituitary Neuroendocrine Tumors and Posterior Pituitary Tumors Based on MRI Radiomic Features

Compared to non-functional pituitary neuroendocrine tumors (NF-PitNETs), posterior pituitary tumors (PPTs) require more intraoperative protection of the pituitary stalk and hypothalamus, and their perioperative management is more complex than NF-PitNETs. However, they are difficult to be distinguished via magnetic resonance images (MRI) before operation. Based on clinical features and radiological signature extracted from MRI, this study aims to establish a model for distinguishing NF-PitNETs and PPTs. Preoperative MRI of 110 patients with NF-PitNETs and 55 patients with PPTs were retrospectively obtained. Patients were randomly assigned to the training (n = 110) and validation (n = 55) cohorts in a 2:1 ratio. The lest absolute shrinkage and selection operator (LASSO) algorithm was applied to develop a radiomic signature. Afterwards, an individualized predictive model (nomogram) incorporating radiomic signatures and predictive clinical features was developed. The nomogram's performance was evaluated by calibration and decision curve analyses. Five features derived from contrast-enhanced images were selected using the LASSO algorithm. Based on the mentioned methods, the calculation formula of radiomic score was obtained. The constructed nomogram incorporating radiomic signature and predictive clinical features showed a good calibration and outperformed the clinical features for predicting NF-PitNETs and PPTs (area under the curve [AUC]: 0.937 vs. 0.595 in training cohort [p < 0.001]; 0.907 vs. 0.782 in validation cohort [p = 0.03]). The decision curve shows that the individualized predictive model adds more benefit than clinical feature when the threshold probability ranges from 10 to 100%. Individualized predictive model provides a novel noninvasive imaging biomarker and could be conveniently used to distinguish NF-PitNETs and PPTs, which provides a significant reference for preoperative preparation and intraoperative decision-making.

Case Report: Sellar Ependymomas: A Clinic-Pathological Study and Literature Review

Ependymomas are primary glial tumors arising from cells related to the ependymal lining of the ventricular system. They are classified into at least nine different molecular subtypes according to molecular phenotype, histological morphology, and tumor location. Primary sellar ependymoma is an extremely rare malignancy of the central nervous system, with only 12 known cases reported in humans. We herein report a case of ependymoma located at the pituitary region in a 44-year-old female patient and discuss the molecular subtype, natural history, clinical presentation, radiological findings, histological features, immunohistochemical characteristics, ultrastructural examinations, treatment, and prognosis of sellar ependymoma. This case report may serve as a helpful reference for clinicians and radiologists in clinical practice.

Nonneuroendocrine Neoplasms of the Pituitary Region

CONTEXT

Although most sellar lesions are related to pituitary adenomas, the region gives rise to a variety of neoplasms that can be associated with substantial morbidity and/or mortality.

DESIGN

Information from reviews and guidelines of relevant societies dealing with such neoplasms, as well as articles that have provided new developments that made important contributions to their pathogenesis and treatment up to 2018, were obtained: public indexes such as PubMed/MEDLINE were used with the relevant search items.

RESULTS

Sellar neoplasms have a worse outcome than pituitary adenomas that is related not only to their natural history but also to side effects of therapies and evolving endocrine and/or hypothalamic deficiencies. Recent imaging advances have established the radiological fingerprint of some of these neoplasms, and several chromosomal aberrations have also been identified. Although established approaches along with new surgical and radiotherapeutic approaches remain the main treatment modalities, recent evidence has provided insight into their molecular pathogenesis involving, other than chemotherapy, treatments with targeted agents as in gliomas and craniopharyngiomas bearing BRAF mutations. Development of predictive markers of recurrences may also identify high-risk patients, including proliferative markers and expression of the progesterone receptor in meningiomas, and lead to less aggressive surgery. Owing to the rarity and complexity of these neoplasms, patients should be managed in dedicated centers.

CONCLUSIONS

The diagnosis and management of sellar neoplasms necessitate a multidisciplinary approach. Following evolving recent advances in their diagnosis and therapy, such a multidisciplinary approach needs to be extended to establish evidence-based diagnostic and management plans.

Primary tumors of the posterior pituitary: A systematic review

In 2017, the World Health Organization established that pituicytoma, granular cell tumor (GCT), spindle cell oncocytoma (SCO) and sellar ependymomas (SE) are posterior pituitary tumors (PPT). They probably arise from the pituicytes and may constitute a unique histopathological entity. We carried out a systematic review using PubMed's database. A total of 266 patients with pathological diagnosis of PPT (135 pituicytomas, 69 GCT, 47 SCO, 8 SE and 7 mixed histology tumors) were analyzed. Gender distribution was identical and median age at diagnosis was 48 ± 21.8 years. Main presentation symptoms were visual disorders (n = 142; 58.1%), headache (n = 99; 40.5%), hypopituitarism (n = 84; 34.4%), hypercortisolism (n = 10; 4.1%), polyuriapolydipsia (n = 6; 2.4%) and acromegaly features (n = 5; 2.0%). On MRI, 122 (47.6%) patients showed sellar with suprasellar extension masses, 67 (23.1%) were suprasellar and 63 (24.6%) exclusively sellar. Median tumor size was 22.0 ± 14.2 mm. Two hundred sixty four patients underwent surgery, transphenoidal access was selected in 132 (64.4%) and craniotomy in 58 (28.3%). Complications were hypopituitarism (n = 70; 42.1%), diabetes insipidus (n = 55; 33.1%) and hemorrhage (n = 50; 30.1%). Tumor persisted in 93 patients (45.6%) and recurred in 13 (6.4%). Regarding comparison between main types of PPT, SCO patients were diagnosed later (60.0 vs 47.0 vs 47.0 years, p = 0.023), the tumor was larger 25.0 mm [10.8] vs 20.0 mm [14.2] vs 2.0 mm [15.0] and they were frequently sellar with suprasellar extension tumors (71.7% vs 46.2% vs 32.8%, p = 0.003) compared to pituicytoma and GCT. In conclusion, PPT are rare tumors and have been misdiagnosed mainly as non-functioning pituitary adenomas. Different types of PPT share similar epidemiology, clinical manifestations and surgical outcomes. Surgery is the only curative option but complications and subtotal resection are common.

Pituitary Ependymoma: A Case Report and Review of the Literature

BACKGROUND

Pituitary ependymoma is exceptionally rare. Its etiology, clinical presentation, radiologic feature, and treatment strategy are still a matter of debate. Only 7 human cases with limited data were reported in the English literature, and now we described another case of pituitary ependymoma. We also systematically reviewed previously reported cases and described its potential etiology, clinical presentation, radiologic features, pathology, immunohistochemical analysis, and ultrastructural examinations.

CASE DESCRIPTION

A lesion in pituitary fossa was discovered in a 40-year-old man after suffering a progressive deterioration of vision in his right eye for >1 year with intermittent headache. The lesion was microsurgically resected and proved to be ependymoma upon pathologic and histologic examination. The patient made a fully recovery after surgery.

CONCLUSIONS

To our knowledge, only 7 patients with ependymoma in the sellar region have been described in the English literature. We reported 1 more case of pituitary ependymoma and discussed the potential etiology, clinical presentation, radiologic features, pathology, immunohistochemical analysis, ultrastructural examinations, treatment, surgery, radiotherapy, chemotherapy, and prognosis of pituitary ependymoma. The case report may serve as a helpful reference for clinicians and radiologists.

Pituitary Ependymoma, 10-Year Follow-Up after Partial Resection and Radiation Therapy

Ependymoma usually arises within the ventricles and central canal of the spinal cord. These tumors, found in the sellar region, are extremely rare. We report a case of pituitary ependymoma followed up over 10 years. A 59-year-old male patient presented with fatigue, general weakness, erectile dysfunction, and loss of body hair, including pubic hair. Brain magnetic resonance imaging (MRI) revealed a 3.3×3.5×2.3-cm sellar and suprasellar snowman-shaped enhancing mass. The tumor was partially resected via the trans-sphenoidal approach followed by postoperative radiation therapy. The pathologic confirmation was pituitary ependymoma. At the 10-year follow up, MRI revealed no evidence of tumor progression. With lack of knowledge about pituitary ependymoma, our case is the only case in which the disease has been well controlled over a long period of time without tumor progression.