Endoscopic resection of a giant colloid cyst in the velum interpositum: illustrative case

BACKGROUND

Colloid cysts are an unusual differential diagnosis for lesions in the lateral ventricles. Microsurgery is usually recommended for the treatment of giant colloid cysts. This case is the largest reported colloid cyst in this unusual location treated with an endoscope.

OBSERVATIONS

A 39-year-old woman with a history of pulsing headaches presented with nausea, vomiting, vision blurring, and paresthesia of the left leg. On the brain computed tomography, a huge, well-defined homogeneous hyperdense intraventricular lesion with hydrocephalus was observed. Magnetic resonance imaging showed a spherical lesion over the third ventricle inside the lateral ventricles, obstructing the Sylvius aqueduct. There was no enhancement and no diffusion restriction on diffusion-weighted images. Endoscopic third ventriculostomy was undertaken for hydrocephalus treatment. Then the lesion was resected grossly. The cyst wall was resected as much as it was safe. There was no clot or bloody product inside the lesion.

LESSONS

Colloid cyst is rarely encountered in the velum interpositum and lateral ventricles, but the authors' giant colloid cyst case along with similar cases led to considering it out of the third ventricle. According to their experience, endoscopic removal is a safe and efficient method for colloid cyst surgery, even in giant cases.

Joint application of biochemical markers and imaging techniques in the accurate and early detection of glioblastoma

Glioblastoma is a primary brain tumor with the most metastatic effect in adults. Despite the wide range of multidimensional treatments, tumor heterogeneity is one of the main causes of tumor spread and gives great complexity to diagnostic and therapeutic methods. Therefore, featuring noble noninvasive prognostic methods that are focused on glioblastoma heterogeneity is perceived as an urgent need. Imaging neuro-oncological biomarkers including MGMT (O⁶-methylguanine-DNA methyltransferase) promoter methylation status, tumor grade along with other tumor characteristics and demographic features (e.g., age) are commonly referred to during diagnostic, therapeutic and prognostic processes. Therefore, the use of new noninvasive prognostic methods focused on glioblastoma heterogeneity is considered an urgent need. Some neuronal biomarkers, including the promoter methylation status of the promoter MGMT, the characteristics and grade of the tumor, along with the patient's demographics (such as age and sex) are involved in diagnosis, treatment, and prognosis. Among the wide array of imaging techniques, magnetic resonance imaging combined with the more physiologically detailed technique of H-magnetic resonance spectroscopy can be useful in diagnosing neurological cancer patients. In addition, intracranial tumor qualitative analysis and sometimes tumor biopsies help in accurate diagnosis. This review summarizes the evidence for biochemical biomarkers being a reliable biomarker in the early detection and disease management in GBM. Moreover, we highlight the correlation between Imaging techniques and biochemical biomarkers and ask whether they can be combined.