Uveal Melanoma: A Prototype for the Study of Organ Targeted Metastasis
Uveal melanoma tends to spread first and almost exclusively to the liver. Conjunctival and eyelid melanomas, by contrast, tends to spread first to regional lymph nodes.
Suggested Reference: McLean IW. The biology of haematogenous metastasis in human uveal malignant melanoma. Virchows Arch A Pathol Anat 2003;422:433-437.
Because the liver is typically the first site of dissemination, there must be a significant metastatic tumor burden before hepatic metastases are detectable by imaging studies or blood tests. Furthermore, a large metastatic tumor burden presents a formidable treatment challenge.
Suggested Reference: Donoso, et al. Metastatic uveal melanoma: diffuse hepatic metastasis in a patient with concurrent normal serum enzyme levels and liver scan. Arch Ophthalmol 1985;103:758.
Location of subclinical micrometastasis in the liver may help to explain the course of those patients who survive for long periods of time following treatment for their primary tumor, but who develop evidence of metatastic disease many years later.
Suggested Reference: Shields JA, et al. Hepatic metastasis and orbital recurrence of uveal melanoma after 42 years. Am J Ophthalmol 1985;100:666-668.