Purpose: To evaluate the outcome of patients with retinoblastoma and postlaminar optic nerve invasion (PLONI).
Design: Retrospective interventional case series.
Participants: Sixty-one consecutive patients included in 3 successive protocols were analyzed.
Methods: Pathologic review was done in each case. Patients were stratified into 2 risk groups: the high-risk group included those with concomitant full choroidal and/or scleral invasion and were given adjuvant chemotherapy. Those without these features were considered low risk and chemotherapy was withheld after 1994.
Main outcome measures: Extraocular relapse and survival according to stratification.
Results: The probability of event-free survival (pEFS) was 0.91 and the probability of overall survival (pOS) was 0.94 at 5 years. Patients in the high-risk group (n = 22) had pEFS of 0.86. Three had extraocular relapse (involving the central nervous system; all died of disease). Microscopic scleral invasion was associated to extraocular relapse (P = 0.05). Lower risk patients (n = 39) had a pEFS of 0.94 and pOS of 1. Eighteen received postenucleation chemotherapy and none relapsed. Twenty-one received no adjuvant therapy and 2 had a systemic relapse but were successfully retrieved. Relapsing patients had a higher ratio of affected optic nerve (>25% of it overall length; P = 0.02).
Conclusions: Patients with PLONI have an excellent outcome with current therapy. Risk stratification according to the presence of concomitant choroidal and/or scleral invasion may help in the decision of giving adjuvant therapy.