Durable response to mTOR inhibition in a patient with relapsing papillary tumor of the pineal region

Papillary tumor of the pineal region (PTPR) was first described as a distinct tumor entity by Jouvet et al in 20031 and was eventually included in the 2007 World Health Organization (WHO) classification of CNS tumors as a rare neuroepithelial tumor characterized by papillary architecture and epithelial cytology.2 PTPR mostly occurs in younger adults and shows frequent local recurrence after surgery, which corresponds to WHO grade II or III.2 So far, there is no established oncological treatment of these patients. We previously described that loss of chromosome 10 and phosphatase and tensin homolog (PTEN), and associated pathological activation of the Akt/mammalian target of rapamycin (mTOR) pathway, is a hallmark of PTPR.3 Here, we for the first time report a patient case with relapsing and rapidly progressing PTPR that showed loss of chromosome 10 and PTEN, phosphatidylinositol-3 kinase (PI3K)/Akt/mTOR hyperactivity, and a dramatic and durable response to mTOR inhibition with everolimus