Use of femoral artery ultrasound during intraarterial chemotherapy for children under 10 kg with retinoblastoma

Purpose: To demonstrate the safety and efficacy of intraarterial chemotherapy (IAC) in small infants (<10 kg) with retinoblastoma. Methods: Retrospective, consecutive, observational case series of patients treated with IAC. Femoral arterial access was obtained using a micropuncture kit and ultrasound guidance, which enabled direct visualization. Melphalan (1.5-5.0 mg), topotecan (0.3-2.0 mg), and/or carboplatin (30-40 mg) were used. Patients underwent adjuvant therapies including laser, cryotherapy, and intravitreal melphalan if persistent disease or recurrence was observed. Results: Fifty-nine injections were administered to 11 eyes of 6 patients. All eyes but one were classified as International Classification Groups C or D. Median patient weight at first IAC cycle was 9.2 kg (mean, 8.9 kg). Median diameter of the femoral artery at the catheterization site was 3.74 mm, measured by two independent observers. Median follow-up was 21.4 months (range 13.1-34.5 months). All eyes were salvaged. Conclusion: This study confirmed the safety and efficacy of IAC in infants under 10 kg. Ultrasound guidance enabled successful catheterization of femoral arteries as small as 2.7 mm in diameter. Patients in this study appeared to require fewer injections and lower total doses of chemotherapy compared with previously reported series of comparably advanced disease in larger infants.