Clinically preventable causes of unfavourable retinoblastoma treatment outcomes

Abstract

Purpose : The primary aim was to identify the frequency of unfavourable outcomes for retinoblastoma. The secondary aim was to determine if any unfavourable outcomes were preventable.

Methods : We conducted a retrospective, non-comparative, single-institution review for children diagnosed with retinoblastoma and exclusively treated at SickKids (1/1/2000-13/7/2015). Unfavourable outcomes were defined as death, metastasis (including extraocular extension), use of external beam radiation therapy (EBRT) and enucleation. Preventable causes were factors that could have avoided an unfavourable outcome (e.g. by a change in practice). Causes were reviewed by a multidisciplinary committee. Main outcome measures were frequency of unfavourable outcomes and preventable causes.

Results : The study included 197 patients (120 unilateral, 77 bilateral, 274 eyes). There were 167 patients with at least 1 unfavourable outcome. Unfavourable outcomes included: 7 deaths (7/197, 3.5%); 8 patients with metastasis (8/197, 4.1%); 8 patients treated with EBRT (8/197, 4.1%) and 138 primary (138/274 50%) and 28 secondary (28/136, 20%) enucleations.

Four patients had preventable causes of unfavourable outcomes. Two had metastasis leading to death; 1 had extraocular extension; and 1 underwent secondary enucleation. One death was associated with a failure of pathology to detect high-risk features of metastasis. One death was related to parental refusal of enucleation. The extraocular extension was related to scleral invasion, potentially facilitated by aggressive focal therapy. The enucleation was related to mismanagement of a treatment complication.

Conclusions : Comprehensive review of unfavourable outcomes for retinoblastoma can identify areas for practice change.

This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.