We thank Drs Meadows and Shields for their reflection on our letterin the October 2003 issue of the ARCHIVES. Interesting aspects of retinoblastomaare brought into the discussion.
The observation of more pinealoblastoma in familial cases of retinoblastomaas compared with de novo germline mutations is interesting. This is in accordancewith our patient group, including 5 patients with familial retinoblastomaof 7 diagnosed as having pinealoblastoma. One explanation might be the expectedsomatic mosaicism in some of the patients with nonfamilial hereditary retinoblastoma.1 This could include a smaller risk for pinealoblastomadue to absence of the RB1 mutation in a proportionof the somatic cells. This concept might be confirmed by pooling the dataon genetic analysis of a larger group of patients with retinoblastoma andpinealoblastoma.
Schouten-van Meeteren AYN, Moll AC, Imhof SM, Dommering CJ. Regarding Chemoreduction for Retinoblastomaand Intracranial Neoplasms—Reply. Arch Ophthalmol. 2004;122(10):1571. doi:10.1001/archopht.122.10.1571-a