Primary orbital and adnexal rhabdomyosarcoma: a study of 54 Asian Indian patients.

Purpose: To describe the clinical presentation, management, and outcomes of orbital and adnexal rhabdomyosarcoma (RMS) in an Asian-Indian cohort and analyze the factors predictive of outcomes.

Methods: Retrospective interventional case series of 54 patients of histopathology-proven RMS.

Results: The mean age of presentation with RMS was 10 years (median, 7 years; range, <1-54 years). The most common tumor location was the superonasal quadrant (n = 21, 39%). Extensions beyond the orbit into the sinuses, temporal fossa, and brain were seen in 15 (28%), 3 (6%), and 8 (15%), respectively. First-line treatment modalities included a combination of surgical debulking, chemotherapy, and external beam radiotherapy in 20 (37%) patients; chemotherapy and radiation in 20 (37%); complete surgical excision and chemotherapy in 3 (6%); orbital exenteration, chemotherapy, and external beam radiotherapy in 1 (2%); chemotherapy alone in 1 (2%) patient, and 9 (17%) patients were lost to follow up. By Intergroup Rhabdomyosarcoma Study Group (IRSG) grouping, tumors belonged to groups I (n = 2,4%), II (n = 13, 29%), and III (n = 30, 67%). Kaplan-Meier survival estimates for tumor recurrence, lymph node metastasis, systemic metastasis, and death (n = 45) were 84%, 82%, 95%, and 95% at 1 year, 69%, 76%, 81%, and 77% at 5 years, 69%, 76%, 81%, and 77% at 10 years, respectively. On multivariate regression, age >18 years was found to have a significantly increased risk of locoregional LN metastasis (p = 0.005).

Conclusion: Despite aggressive treatment modalities, the 5-year disease-specific survival rate was 77% in Asian-Indian cohort. Age > 18 years at presentation was associated with a poorer prognosis.