Abstract
Abstract: :
Purpose: To report patient and ocular outcome following initial treatment with external beam radiation therapy (EBT) in eyes with Reese-Ellsworth (RE) Group Vb retinoblastoma (Rb). Methods: Retrospective case series of 555 patients diagnosed with Rb at our center (1/1979- 2/2002). Patients were identified who initially presented with > 1 RE Group Vb eye. The following data points were recorded: demographics, treatment course, visual acuity, ocular complications, and 2nd tumor development. Ocular and patient survivals were analyzed using the Kaplan-Meier method. Results: 63/284 RE Vb eyes (22%) initially received EBT, versus 172/284 (61%) eyes initially enucleated. 53 (84%) of the 63 eyes were in bilateral patients. 31/63 (49%) of the radiated RE Vb eyes had no further tumor growth; 26/63 (41%) developed a recurrence and 8/63 (13%) developed new tumor. 33/63 (52%) eyes developed ocular complications. The ocular survival rate of RE Vb eyes following initial EBT treatment was 81% at 1 year, 56% at 5 yrs, and 53% at 10 yrs. Of the 36 eyes that survived, the majority (58%) had > 20/400 vision. 13 patients developed 2nd, non-ocular cancers: 10/13 (77%) received EBT as the initial treatment for the RE Vb eye(s) and 13/13 (100%) received EBT at some point during treatment for intraocular disease. 12/13 had bilateral disease. 11/13 2nd cancers were in the field of radiation. The probability of developing a 2nd non-ocular cancer following initial EBT for RE Vb eyes in bilateral patients was 30% by 10 yrs post-diagnosis. Patient survival in all patients diagnosed with > 1 RE Vb eye (n=243) is 95% (5 yrs), 84% 11 yrs, and 70 % (18.25 yrs). Patient survival (from metastatic Rb and 2nd non-ocular cancers) for all bilateral patients with > 1 RE Vb eye was 92% (5 yrs), 76% (11 yrs), and 51% (18.25 yrs). Patient survival from 2nd non-ocular cancers in bilateral patients initially receiving EBT for > 1 RE Vb eye was 94% (5 yrs), 79% (11 yrs), and 53% (18.25 yrs). No deaths occurred in bilateral patients with > 1 Vb eye who never received EBT for intraocular Rb. Conclusions: Although many studies have focused on results of EBT for Rb, this is the first study to exclusively focus on results of Reese Ellsworth Vb eyes treated initially with EBT. The outcome variables of patient survival, ocular survival and 2nd tumor incidence in this cohort may be useful when comparing similar outcome data after other treatment modalities, such as systemic chemotherapy.
Keywords: retinoblastoma • radiation therapy • oncology