Analysis of misdiagnosed retinoblastoma in a series of 726 enucleated eyes.

Of 726 eyes consecutively enucleated at the Mayo Clinic from 1954 through 1974, 41 contained retinoblastoma. In no instance was unsuspected retinoblastoma identified, nor could retinoblastoma be confirmed pathologically in an additional eight eyes in which retinoblastoma was considered in the differential diagnosis. In each of our eight misdiagnosed cases, the eyes were already blind and were cosmetically defective. The frequency of clinical misdiagnosis of retinoblastoma is high in part because it must be considered in every case of leukokoria. Although every effort was made to arrive at an accurate clinical diagnosis, the clinical misdiagnosis of retinoblastoma in a blind eye is of far less serious consequence than the clinical misdiagnosis of a tumor in a seeing eye.