Management of uni- or bilateral retinoblastoma with radiologic optic nerve invasion at diagnosis.

Abstract

10551 Background: To evaluate treatment and outcome of patients with uni- or bilateral retinoblastoma (RB) with radiologic optic nerve invasion (RONI) at diagnosis. Methods: Retrospective clinical, radiological and histological review of patients with uni- or bilateral RB with RONI at diagnosis treated in the Institut Curie. Results: Between 1997 and 2014, 936 patients with RB were treated in the Institut Curie. Eleven patients had detectable RONI confirmed by Computed Tomography and/or Magnetic Resonance Imaging. RB was unilateral in 10/11 patients, bilateral in 1. Median age at diagnosis was 29 months (range 12-96). The patient with the bilateral RB had a unilateral RONI. Nine patients had ON enhancement and 3 had meningeal sheath enhancement. Nine received neoadjuvant chemotherapy (CT) and 2 had a primary enucleation. Partial response to neoadjuvant CT was obtained for all the patients. Enucleation was performed in 10/11 patients, by anterior approach in 3 patients, by anterior and subfrontal approach in 7 patients. Three patients had positive ON margin and among them, 2 were primary enucleated. All enucleated patients received adjuvant treatment (conventional CT: 10, High Dose CT: 7 and radiotherapy: 5). Three patients died of meningeal progression (2 during treatment and 1 during the first year after treatment). The patient with the bilateral RB was lost to follow up just after a meningeal progression during treatment. Seven are still alive (median follow up: 8 years, range : 1.5-17.5). Conclusions: Neoadjuvant CT has an important place in the management of unilateral RB with RONI at diagnosis. Pretreatment accurate staging by orbital and brain MRI is mandatory, as well as preoperative reassessment. Surgery should be performed by experienced ophthalmologists and if necessary neurosurgical team in order to obtain the best conditions for a tumor-free resection margin in patients with RONI.