Cytopathological Evaluation of Ocular Surface and Needle Washings Following Intravitreal Melphalan Injections for Retinoblastoma

Purpose: There is concern that injections into eyes with retinoblastoma are dangerous and allow tumor escapement. This study attempted to determine this risk by investigating the presence of malignant cells in ocular surface and needle washings of eyes with retinoblastoma receiving intravitreal injections. Methods: Two hundred ocular surface and 202 needle washings were obtained from 280 injections into eyes with retinoblastoma. Each specimen underwent cytopathlogical assessment for the presence of malignant cells. Results: Cytopathological results revealed no malignant cells in all 200 ocular surface and 202 needle washing specimens. In the ocular surface washings, squamous cells, red blood cells, and inflammatory cells were found in 15, 2, and 2 specimens, respectively. In the needle washings, 4 specimens contained squamous cells but no red blood cells or inflammatory cells were found in any specimen. Conclusion: With this injection and evaluation technique, no malignant cells were recovered, highlighting the low risk of the procedure.