PREDICTIVE VALUE OF TNM CLASSIFICATION, INTERNATIONAL CLASSIFICATION, AND REESE-ELLSWORTH STAGING OF RETINOBLASTOMA FOR THE LIKELIHOOD OF HIGH-RISK PATHOLOGIC FEATURES.

PURPOSE: To evaluate the predictive value of the seventh edition American Joint Committee on Cancer (AJCC/UICC) TNM classification, the International Classification of Retinoblastoma (ICRB), and Reese-Ellsworth staging for retinoblastoma for the likelihood of high-risk pathologic features. METHODS: A retrospective study of 50 primarily enucleated eyes from 49 retinoblastoma patients. Main outcome measures included demographics, TNM stage, ICRB group, Reese-Ellsworth stage, choroid, optic nerve, and anterior chamber invasion. RESULTS: The median age at enucleation was 30 months. High-risk pathologic features mandating adjuvant chemotherapy were seen in 5 of T2 eyes (22%), in 15 of T3 eyes (56%) (P = 0.021), in 1 of ICRB Group C eyes (13%), 8 of Group D eyes (33%), and 11 of Group E eyes (61%) (P = 0.035). High-risk pathologic features were 4.61 and 3.68 times more likely to be diagnosed at a more advanced T stage and ICRB group consecutively, whereas 0.133 time less likely to be diagnosed at a more advanced Reese-Ellsworth stage. At median follow-up of 40 months, no single case had metastasis or was dead. CONCLUSION: The higher tumor clinical TNM stage and the more advanced ICRB group at presentation are associated with higher frequency of high-risk pathologic features and may predict which patients should receive adjuvant chemotherapy.