Abnormal mitochondria in retinoblastoma.

In examination of six retinoblastoma tumor specimens, bizzare mitochondria were often found. Some are irregular forms with focal expansion and constrictions. Occasionally, a portion of the mitochondria forms rings. Branching mitochondria are also seen. Other striking features of the mitochondria from tumor cells are the alternation of cristae. Dense bodies are also occasionally observed within the mitochondria. Morphological modifications of the mitochondria may be as results of pathological conditions of the tumor cells.