Metastatic tumors to the uveal tract are the most common intraocular tumors in adults when eyes have been examined in large autopsy series. When these lesions are identified clinically, they most often involve the choroid, but metastatic disease can affect any part of the uvea. Unlike primary uveal melanoma, uveal metastatic lesions are often multiple and may be bilateral. They are typically flat, nonpigmented lesions, but rare cases of collar-button or mushroom-shaped lesions have been reported. The most common primary tumors metastasizing to the eye are breast carcinoma in women and lung carcinoma in men (Fig 12-27), although tumors from many different primary sites have been reported. Histologically, metastatic tumors may recapitulate the appearance of the primary lesion, or they may appear less differentiated. Special histochemical stains and a panel of immunohistochemical stains can be helpful in diagnosing metastatic lesions, determining the origin of the primary tumor, and, in some cases, guiding therapy for that tumor. The importance of a careful clinical history cannot be overemphasized. See Chapter 20 for further discussion of metastatic tumors.
Figure 12-27 Choroidal metastasis. A, Clinical appearance of a metastatic lesion from a primary lung tumor. B, Gross appearance of the same lesion shown in part A(between arrowheads).C, Choroidal metastasis from lung adenocarcinoma; histology shows adenocarcinoma (between arrows) with mucin production (asterisk). Note the overlying exudative retinal detachment. D, Higher magnification depicts a well-differentiated adenocarcinoma with a distinct glandular morphology.
(Courtesy of Hans E. Grossniklaus, MD.)
Excerpted from BCSC 2020-2021 series: Section 4 - Ophthalmic Pathology and Intraocular Tumors. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.