Chemoreduction failure in D-E intraocular retinoblastoma, single center experience

Background: Retinoblastoma (Rb) is the most common intraocular tumor in childhood. Systhemic chemotherapy (ChT) with vincristine, carboplatin and etoposide (chemoreduction) combined with local therapy (laser photocoagulation, cryotherapy and brachytherapy) was the standard of care for more than a decade. We present data focused on eye preserving after chemoreduction.

Material and Methods: Since 1999 to the end of 2013, 74 children (5.2/year), 96 eyes (6.8/year) with retinoblastoma were diagnosed at our institution (22 patients had bilateral retinoblastoma, 1 patient had trilateral Rb). Median age at diagnosis was 16 months (0–104.8 months). Initial enucleation was performed in 23 patients (24.0%), 2 patients were treated with selective intra-arterial ChT to arteria ophthalmica and chemoreduction, all are excluded from analysis. Chemoreduction and local therapy were used in 71 eyes, according to International Classification of Rb (ICRb): 7 were A, 19 B, 14 C, 22 D, 9 E. Failure of chemoreduction was defined as tumor progression and enucleation of affected eye, use of external beam radiotherapy (EBRT), other ChT regimen (vincristine, topotecan) or selective intra-arterial ChT for salvage.

Results: All patients were initially treated with chemoreduction and local therapy; failure was diagnosed in 36 cases (50.7%). Five eyes received additional salvage EBRT, all were enucleated subsequently. Vincristine, topotecan ChT regimen was used for the salvage in 3 cases, 1 eye was enucleated; intra-arterial ChT in 1 case, eye was subsequently enucleated. Altogether, 34 eyes from 71 (47.9%) had to be enucleated for persistence or relapse of retinoblastoma. According to ICRb A: 0%, B: 0%, C 35.8%, D 90.1%, E 100% eyes were enucleated. In 16 cases (47.1%) time from diagnosis to enucleation was lower than 1 year, in 12 cases (35.3%) 1 to 2 years, 4 (11.8%) 2 to 3 years and in 2 cases (6.1%) more than 3 years.

Conclusions: Chemoreduction is effective in small Rb (IRCb A and B), but is not very successful in retinoblastoma with seeding (ICRb C and D) and/or large retinoblastoma (ICRb E). In small Rb, the ChT could be reduced. On the other hand, in Rb with seeding or large Rb, the application of new methods (selective intra-arterial ChT, intra-vitreal ChT) could be the option for treatment of these patients. New large investigations are needed.

No conflict of interest.