Beyond the 5-Year Window: Late-Onset Ocular Morbidity and a Proposed 10-Year Functional Survivorship Protocol for Pediatric Orbital Rhabdomyosarcoma

Background: Orbital rhabdomyosarcoma (RMS) is the most common primary pediatric malignant orbital tumor, typically curable with chemotherapy and radiation. Data regarding MRI chemotherapy response and long-term ophthalmologic outcomes remain limited in non-cooperative-group settings. Methods: We retrospectively reviewed children with primary orbital RMS treated at King Hussein Cancer Center (2002–2025) with vincristine, actinomycin-D, and cyclophosphamide (VAC). Pre-local-control MRI responses were classified as complete (CR), partial (PR), stable/minor (SD/MR), or progressive disease (PD). Survival and ophthalmologic outcomes were analyzed. Results: Twenty-two patients (median age 5.6 years) were included. All had localized disease (77% low-risk). All received VAC; 20 (91%) received radiotherapy (median 45 Gy). Pre-radiotherapy MRI showed 8 (36%) CR and 11 (50%) PR. Four patients (18%) died. Five-year event-free survival (EFS) and overall survival (OS) were 73% and 84%, respectively. Cataracts developed in 45% of the cohort (50% of irradiated patients) at a median of 39.1 months (range 9.4–95.1). At last assessment, visual acuity was good in 60%, moderate in 25%, and severely impaired in 15%. Conclusions: Excellent survival in orbital RMS is achievable in resource-stratified settings. Induction MRI progressive disease (PD) was associated with poor outcomes in this cohort and may represent an early prognostic signal warranting further validation in larger studies. Furthermore, the documented maximum cataract latency of 95 months suggests that the standard 5-year surveillance window is insufficient. These findings support extending ophthalmologic surveillance beyond the standard 5-year window. We propose, based on our retrospective institutional data, a 10-year functional survivorship framework.