Studies of ocular retinoblastomas with immunoperoxidase techniques

15 cases of ocular retinoblastomas, 10 differentiated and 5 undifferentiated, were studied with the following antibodies: neuron-specific enolase, S100, and tubulin. All cases turned out negative with S100 and tubulin labeling. The well-differentiated retinoblastomas were NSE-positive, and only 2 of the 5 undifferentiated retinoblastomas were positive for the same antibody. The observed results let us conclude that S100 and tubulin are not useful in diagnosing this entity and that enolase, although it showed its value in the differentiated retinoblastomas, did not have the same effect in the undifferentiated retinoblastomas, as it was negative in 3 out of 5 cases.