Concurrence of chordoid gliomas with Rosai-Dorfman component: report of two rare cases.

Chordoid glioma (CG), which often originated from the third ventricle, was a type of rare and slowly growing low grade glioma with chordoid appearance. So far, concurrent occurrence of third ventricule chordoid gliomas with Rosai-Dorfman disease (RDD) has never been observed. In this study, the clinical features, pathological characteristics as well as their prognosis of two CG with RDD component cases were discussed. Herein, we reported two cases of CG with RDD component from a 45-year-old female and a 38-year-old male respectively. Radiologically, the two lesions were located on the region of suprasellar-third ventricular with homogenous contrast enhancement. They underwent gross total resection and remained free of disease progress till now. Microscopically, both lesions showed the classic morphology of CG and RDD component. A morphologic curiosity is presented in tumors manifested by CG with RDD component in the suprasellar-third ventricular region. To the best of our knowledge, this is the first presentation of two collision tumors consisting of CG and RDD on the suprasellar-third ventricular region. Awareness of this entity is important to distinguish it from other CGs. More examples and a timely follow-up are required for understanding the biological features of these cases.