Retinoblastoma Cell Culturing and Evaluation of Their Drug Resistance.

We obtained primary culture of retinoblastoma cells and evaluated the resistance of cultured ells to chemotherapy. The study included 19 patients aged 6-64 months (mean 27.9±17.4 months); of these, 6 (31.6%) patients with bilateral retinoblastoma and 13 (68.4%) patients with unilateral form. In 18 (94.7%) patients, group E retinoblastoma was diagnosed. Enucleation was performed in all patients; in 94.7% cases, low-differentiated retinoblastoma was identified. Samples of the tumor tissue were taken to derive a cell culture and to study drug resistance and metabolic activity of cells (MTT test). In 4 cases, adhesion primary cultures of retinoblastoma were derived. Cytological verification of the obtained cultures was performed. The primary cultures were derived from 4 of 6 bilateral tumors and from none of 13 unilateral tumors (p=0.003). There were no statistically significant correlations with patient age (p=0.33) and the presence of calcifications in the tumor (p=0.26). MTT test revealed no differences in the sensitivity of cell cultures to irinotecan and ifosfamide. Pronounced differences in the resistance of cell cultures were observed for oxaliplatin and ascorbic acid. MTT test with evaluation of drug resistance can be used both in clinical practice for adjusting chemotherapy regimen and in development of new approaches to the treatment of retinoblastoma with assessment of in vivo tumor cell resistance in animal models.