Malignant epibulbar melanoma: natural history and treatment by radiotherapy.

One hundred and eighty-four cases of malignant melanoma of the lids and epibulbar region were seen in the Radiotherapy Department of the Royal Marsden Hospital during the period 1943-74. Some of these tumours were radiosensitive and could thus be treated by radiotherapy without loss of the affected eye. Their clinical and histological features are described. The treatment policy adopted was based on radiotherapy first, and surgery reserved for the failures. A policy of observation is advised for precancerous melanosis, and active treatment should be undertaken only if malignancy supervenes. The contraindications for radiotherapy, the factors governing radiosensitivity, and the incidence and site of metastases are reported, and the possible effect on the metastatic and survival rates of leaving the eye are discussed. Active treatment of the node-free neck is not advised. Results are given according to site, histology, and treatment method, and the frequency with which the eye was lost is shown, since the sole advantage of radiotherapy over surgery is the possibility of saving the eye without worsening the prognosis for survival.