Outcomes of Children Diagnosed with Unilateral Retinoblastoma: Retrospective Audit

Abstract

To evaluate treatment outcomes of children diagnosed with unilateral retinoblastoma. Retrospective study of children diagnosed with unilateral retinoblastoma registered at the Tata Memorial Hospital (TMH), Mumbai from January 2013 to December 2018 and completed the planned curative treatment protocol. For the 98 cases that were analyzed, the median age of presentation was 24 months. The majority of patients had the intraocular disease (n = 72), whereas orbital retinoblastoma was in 26 patients. At the time of presentation, on imaging extra scleral spread was observed in 16 patients whereas 18 patients had optic nerve involvement, 11 patients had both extra scleral invasion and optic nerve involvement. We used the International Classification of Retinoblastoma for grouping. Out of 98 patients, 71 patients were in Group E, 21 were in Group D and 4 were in Group B and 2 were in Group C. For Staging of Retinoblastoma, we used International Retinoblastoma Staging System (IRSS) in our study and 14 patients had Stage 0 disease, 52 patients had Stage I disease, 10 patients had Stage II, 21 patients had Stage III A and 1 patient had Stage III B disease. High-risk features on surgical specimen histopathology were optic nerve cut margin positive in 6 patients, optic nerve involvement in 21 patients, extra scleral spread in 3 patients, Choroidal invasion in 38 and Iris involvement in 10 patients. Primary enucleation was offered in 52 patients whereas 26 patients underwent secondary enucleation. Systemic chemotherapy was received by the patient in the neoadjuvant setting in 17 patients as a form of chemo-reduction and 51 patients received systemic chemotherapy in the adjuvant setting. Intra-arterial chemotherapy was offered to 27 patients as a primary treatment or in conjugation with focal therapy (n = 11). Definitive radiotherapy was offered to only 2 patients and 22 patients received adjuvant radiotherapy. At a median follow-up of 62 months, 2patients had local relapse, which was salvaged by focal therapy in one and enucleation in the other. Ten patients who had leptomeningeal relapse had died. The 5-year local control (LC) is 97.6%, event-free survival (EFS) is 88% and overall survival (OS) is 89.5%. Globe was salvaged in only 16 cases. On univariate analysis, we observed a significant association between overall survival and extraocular and intraocular disease (p-value 0.0), Extra scleral spread (p-value 0.0), optic Nerve involvement (imaging), and an optic nerve cut margin positive (p-value 0.045), ICRB Groups (p-value 0.0) and IRSS stage (p- value 0.024). Retinoblastoma is curable if detected early. Extra ocular disease and high-risk features are associated with inferior outcomes and poor globe salvage rates.