Iris extramedullary hematopoiesis in choroidal melanoma

Abstract

Purpose: Extramedullary hematopoiesis (EMH) usually occurs in patients with loss of bone marrow hematopoietic function, and in a vast majority of cases, it involves the liver, the spleen, or the lymph nodes. We report EMH in the iris of patients enucleated for choroidal melanoma (CM).

Methods: We report a series of three patients with CM, two treated with primary enucleation and one with secondary enucleation.

Results: Histopathology revealed EMH in the iris of all patients.

Conclusion: EMH of the iris can be associated with CM in the absence of any hematological or systemic disorders. To the best of our knowledge, our work is the first report of this abnormal histopathological finding.

Keywords: Choroidal melanoma; enucleation; iris extramedullary hematopoiesis.

Figure 1

(a) Iris of Patient 1 showing a central cluster of abnormal cells (H and E, ×20). Majority of the cells have dense eosinophilic cytoplasm and rounded nuclei consistent with erythroblasts. (b) Iris of Patient 2 showing clusters of mixed cells including erythroblasts (H and E, ×20) (positive with glycophorin A immunohistochemistry, c) and other primitive cells with little cytoplasm (positive with CD117 immunohistochemistry, not shown). (d) Iris stroma of Patient 3 showing clusters of erythroblasts (H and E, ×20)