Pineoblastoma

Pineoblastoma, which was previously conventionally grouped with embryonal tumors, is now categorized by the World Health Organization (WHO) as a pineal parenchymal tumor. Given that therapies for pineoblastoma are quite similar to those utilized for embryonal tumors, the previous convention of including pineoblastoma with the central nervous system (CNS) embryonal tumors is followed here. Pineoblastoma is associated with germline mutations in both the RB1 gene and in DICER1, as described below:

• Pineoblastoma is associated with germline mutations in RB1, with the term trilateral retinoblastoma used to refer to ocular retinoblastoma in combination with a histologically similar brain tumor generally arising in the pineal gland or other midline structures. Historically, intracranial tumors have been reported in 5% to 15% of children with heritable retinoblastoma.[5] Rates of pineoblastoma among children with heritable retinoblastoma who undergo current treatment programs may be lower than these historical estimates.[6-8]
• Germline DICER1 mutations have also been reported in patients with pineoblastoma.[9] Among 18 patients with pineoblastoma, 3 patients with DICER1 germline mutations were identified, and an additional 3 patients known to be carriers of germline DICER1 mutations developed pineoblastoma.[9] The DICER1 mutations in patients with pineoblastoma are loss-of-function mutations that appear to be distinct from the mutations observed in DICER1 syndrome–related tumors such as pleuropulmonary blastoma.[9]

(Source NCI)