Local treatment efficacy in different stages of retinoblastoma

Background . Nowadays local modalities play an important role in retinoblastoma (Rb) treatment. Despite a great number of publications in scientific literature about local treatment there are no scientific works about comparative analysis of treatment results depending on tumor stage. Purpose of the study – to evaluate the efficacy of local ophtalmological modalities of Rb treatment in different tumor stages. Materials and methods . The study includes 274 patients (357 eyes) with Rb treated from 2007 to 2022. The mean patients’ age at the time of treatment was 15 months (from 0 to 74 months), 58 % patients were male, 42 % – female. 193 (70 %) patients presented with binocular Rb, 81 (30 %) – with monocular. In 59 (22 %) patients local treatment was performed on the single eye. Tumors’ distribution by stages was as followed: T1a stage (group А) – 74 (21 %) eyes, T1b (group В) – 122 (34 %) eyes, T2a (group C) – 56 (15 %) eyes, T2b (group D) – 104 (29 %) eyes, T3 (group E) – 3 (1 %) eyes. As local methods thermotherapy, cryotherapy and brachytherapy were applied. The follow-up varied from 6 to 158 months (median – 49 months). Results. Local treatment modalitites were analyzed by following criteria: local tumor control, complications, eye salvage, number of applied treatment modalities, mean regression period and survival (overall and disease-free). Results were analyzed overall and by comparative analysis on different tumor stages. Local tumor control was achieved in 93 % of cases (n = 328), in 7 % (n = 26) tumor relapse was observed. Local treatment complications were observed in 23 % of cases (n = 82). 329 eyes (93 %) were salvaged, 25 eyes (7 %) were enucleated. All of these criteria were significantly lower in eyes of patients with Rb of group D (p < 0.01). Comparative analysis in different stages showed that tumor stage significantly affected local tumor control (p = 0.0012), complications’ frequency (р = 0.001), eye salvage percentage (р < 0.0001) and doesn’t affect regression period (p = 0.3), number of treatment modalities (p = 0.3), overall (p = 0.74) and disease-free survival (p = 0.3). Conclusion. Local methods showed high efficacy in Rb treatment. Initial tumor stage is relevant in the prognosis of the treatment efficacy. Treatment of patients with Rb of group D still remains to be challenging in aspects of local tumor control and eye salvage.