Clinical Outcomes of Group D Retinoblastoma at a Tertiary Care Hospital in Pakistan.

Purpose To evaluate the clinical outcomes of Group D retinoblastoma (RB) managed with intravenous chemotherapy (IVC) and local therapies at a tertiary care center in Pakistan over nine years, with a focus on globe salvage rates and their implications for resource-limited settings. Methods This retrospective, cross-sectional study included patients diagnosed with Group D RB, classified under the International Classification of Retinoblastoma (ICRB), at Patel Hospital, Karachi, from April 2013 to December 2022. Data were collected on demographics, presenting symptoms, laterality, treatment protocols, and outcomes. Tumor evaluation was conducted under general anesthesia using indirect ophthalmoscopy. The primary treatment involved IVC with vincristine, etoposide, and carboplatin, supplemented by local therapies such as laser and cryotherapy. Intravitreal melphalan was administered in select cases with persistent vitreous seeds. Kaplan-Meier survival analysis was used to estimate globe salvage rates at one, two, and three years. Results Out of 170 patients with RB, 19 were identified with Group D disease, and 15 underwent globe salvage attempts. The median age at diagnosis was 32 months, and bilateral disease was predominant (93%). Leukocoria (60%) and strabismus (20%) were the most common presenting signs. Globe salvage was achieved in 73.33% (11/15) of eyes, with a mean follow-up duration of 57.5 weeks (range: seven to 263 weeks). Kaplan-Meier survival rates demonstrated overall globe salvage rates of 93%, 76%, and 65% at one, two, and three years, respectively. Four eyes of four patients underwent secondary enucleation due to tumor recurrence, retinal detachment, or persistent vitreous seeds, with histopathological findings of high-risk features in two cases. Importantly, no cases of metastasis or mortality were reported during the study period. Conclusion This study highlights the feasibility and effectiveness of IVC coupled with local therapies in achieving high globe salvage rates in Group D RB, even in resource-limited settings. Despite the challenges of advanced disease presentation and socioeconomic barriers, these results underscore the importance of multidisciplinary care and the need to expand access to specialized treatment centers in low- and middle-income countries (LMICs). Future efforts should focus on early diagnosis and the implementation of standardized treatment protocols to improve outcomes for advanced RB.