1. The most common tumor of the choroid is metastatic tumor, with the lung as the primary site. Diagnosis may be difficult in distinguishing a choroidal melanoma from a metastatic lesion. 2. Careful metastatic evaluation may not identify an original primary tumor. Tests may not be sensitive enough to disclose adenocarcinoma until it has reached an advanced stage. 3. External beam radiation may not always be successful in treating choroidal metastases.
