Chordoid glioma in suprasellar location with extension into the third ventricle: smear preparation morphology of a rare tumor

Cytological features of diffuse and circumscribed gliomas

The current World Health Organization classification of gliomas is based on morphological, genetic, and molecular parameters. In this review, we intend to present the most relevant cytological features of these tumours, with a particular focus on their analysis during intraoperative studies. Rapid diagnosis is required in this context, and at present it is not possible to evaluate the genetic or molecular profile of a tumour intraoperatively. New terminology and diagnostic parameters have been introduced, but the essence of intraoperative recognition remains the same. The main challenge in astrocytoma IDH-mutant, grade 2 is recognising the tissue as neoplastic. Since glioma grades 3 and 4 are assigned based on histological and genetic variables that are not necessarily measurable on cytology, the term high-grade glioma is often used for intraoperative diagnosis. Oligodendroglioma, IDH-mutant and 1p/19q-codeleted shows peculiar cytological findings as well as the common subtypes of glioblastoma IDH-wildtype (giant cell, epithelioid, gliosarcoma and small cell). Many of the paediatric-type-diffuse gliomas have been described very recently and there are no cytological reports of proven cases. Finally, pilocytic astrocytoma, pleomorphic xanthoastrocytoma, subependymal giant cell astrocytoma, chordoid glioma, and astroblastoma MN1-altered constitute the group of circumscribed astrocytic gliomas. They are remarkable entities that the pathologist must be able to recognise since most are low-grade neoplasms that can show atypical morphological features.

Cytological features of chordoid glioma: A case report with summary of prior published cases

Chordoid glioma is an uncommon low-grade glioma and is a CNS WHO grade 2 tumour in the current WHO 2021 classification. Predominantly it is seen in the third ventricle and in young adults. Although the histological features of chordoid glioma are well documented, there is sparse literature describing its cytological features. Here we describe the squash cytological features of a case of chordoid glioma along with summary of prior published cases. The smears tend to be quite cellular, the cells show mild pleomorphism, anisonucleosis, and absent mitotic activity. The background shows a distinctive bluish myxoid stroma. It can be mistaken for high grade glioma on squash cytology.

Pituicytoma with pleomorphism: A case report with cytological findings

Pituicytoma is a rare neoplasm, arising in the posterior pituitary or in the hypophyseal stalk, and its cytological findings have not yet been well-described. We have experienced a case of pituicytoma, which was difficult to diagnose intraoperatively, because of its cellular pleomorphism. A tumor measuring 18 mm in maximum diameter was found at the sella turcica in a Japanese woman in her forties. Both intraoperative crush cytology and histology of the resected tumor showed pleomorphic spindle or round cells, including multinucleated cells. Tumor cells were positive for TTF-1, S-100 protein, and vimentin, partially positive for glial fibrillary acidic protein and epithelial membrane antigen, and negative for synaptophysin, hormones of the anterior pituitary gland, CD34, Olig2, PAX8, and napsin A. Ki-67 labeling index was 2.0%. Tumors included in the differential diagnosis in general are pituitary adenoma, craniopharyngioma, germinoma, and metastatic tumor on the radiological standpoint, and pilocytic astrocytoma and meningioma on the cytological standpoint. However, our case was difficult to differentiate especially from high-grade glioma only by morphology, and immunohistochemistry including TTF-1 was helpful.

Cytologic Features of Ventricular Tumors of the Central Nervous System: A Review with Emphasis on Diff-Quik Stained Smears

BACKGROUND

Neoplasms from the ventricular system share a common location but have highly variable histogenesis. Many are slowly growing tumors that behave in a benign fashion. They can be classified as primary and secondary tumors. The most common primary tumors are ependymomas, subependymomas, subependymal giant cell astrocytomas, central neurocytomas, choroid plexus tumors, meningiomas, germinomas, pineal parenchymal tumors, papillary tumors of the pineal region, chordoid gliomas, rosette-forming glioneuronal tumors of the fourth ventricle, and craniopharyngiomas. Pilocytic astrocytomas, medulloblastomas, and atypical teratoid/rhabdoid tumors often show secondary involvement of the ventricular system.

SUMMARY

Advances in neurosurgery have facilitated access to the ventricular system increasing the number of cases in which such tumors can be biopsied. In this context, cytology has been proven to be an extremely useful diagnostic tool during intraoperative pathologic consultations. Many ventricular tumors are infrequent, and the cytologic information available is limited. In this review, we describe the cytologic features of the uncommon ventricular tumors and report on unusual findings of the more common ones. For the cytologic evaluation of brain tumors, many neuropathologists prefer formalin fixation and hematoxylin and eosin staining. In this review, we highlight the cytologic findings as seen with Diff-Quik, a very popular staining method among cytopathologists. In fact, when pathologists are unfamiliar with cytology, it is common to request the assistance of cytopathologists during the evaluation of intraoperative procedures. Key Message: Ventricular tumors of the central nervous system comprise a group of heterogeneous tumors with very different cytologic features. The cytomorphology of these tumors, including rare entities, is often very characteristic, allowing a precise recognition during intraoperative pathologic consultations. Diff-Quik is a valuable staining method that can be used alone or as a complement to hematoxylin and eosin staining. Diff-Quik allows for clear visualization of the overall architecture, cytoplasmic details, and extracellular material.

Prognostic factors for recurrence and complications in the surgical management of primary chordoid gliomas: A systematic review of literature

OBJECTIVE

Chordoid gliomas (CG) are rare neoplasms which frequently arise within the third ventricle. Surgery remains the mainstay treatment for CG. The present study comprehensively reviews all reported cases of CG within the literature in order to identify risk factors for surgical complications and tumor recurrence.

METHODS

A comprehensive search on MEDLINE (OVID and PubMed), Scopus, Embase, and Web of Science was conducted following PRISMA guidelines to identify all reported cases of CG.

RESULTS

A total of 81 patients met the study criteria which comprised of 33 males and 48 females. Median age at diagnosis was 48 years with a range from 5 to 72 years, and mean tumor size was 3.1cm. Biopsy, subtotal resection (STR), and gross total resection (GTR) were achieved in 8, 34, and 33 patients, respectively, with six cases not reporting extent of resection (EOR). Thirteen patients underwent adjuvant radiotherapy. Postoperative complications were noted in 30 cases (37%), with new onset diabetes insipidus being the most common. Postoperative morbidity was not associated with age, tumor size, or extent of resection. A trans-lamina terminalis approach demonstrated a strong trend towards decreased overall rates of postoperative morbidity compared to other approaches (p=0.051). GTR was associated with improved progression-free survival (PFS; p=0.028), while adjuvant radiotherapy, age, tumor size and proliferative index were not predictive of patient outcomes.

CONCLUSION

GTR should be the primary goal for the management of CG, as it is associated with improved rates of tumor control without an increased rate of postoperative complications. Surgical approach was a stronger predictor of complication rates than extent of resection. Morbidity remains high, and future studies to further elaborate on factors predictive of postoperative complications are critical.

Chordoid glioma: a rare radiologically, histologically, and clinically mystifying lesion

Chordoid glioma (CG) is a rare central nervous system neoplasm (WHO grade II) of uncertain origin whose typical localization is in the anterior part of the third ventricle. Its clinical, radiological, and histological features may vary and furthermore mimic other kind of benign lesions usually associated with a better outcome. We report a case of a 43-year-old female who underwent gross total removal of a lesion of the third ventricle causing hydrocephalus. The imaging studies and the intraoperative examination led at first to a hypothesis of meningioma. Early surgical and neurological outcomes were good. The patient underwent multiple complications related to hypothalamic dysfunctions and thrombohemorragic issues and eventually died because of systemic infections. Definitive examination was of chordoid glioma of the third ventricle. Reviewing literature, we evaluated possible pitfalls in radiological and histological diagnosis as well as in surgical and medical treatment of CGs. Despite their benign presentation, a high incidence of multiple possible severe complications is reported. Early alertness and combined treatment strategies could improve overall CGs treatment strategies.