The prognostic value of uveal melanoma cell type

Abstract

To determine the prognostic value of a uveal melanoma (UM) cell type for the development of metastases (MTS). The investigation enrolled 96 patients (96 eyes) with UM after enucleation. Forty-one patients without signs of MTS were included in this group, who were followed up for more than 36 months (mean, 70.5 months (36 to 105 months)), 55 patients with MTS who were followed up for an average of 21 months (2 to 44 months). The MTS and non-MTS groups were statistically homogeneous in age, gender, tumor size, location, and ciliary body involvement in the process, as well as in extrabulbar growth. There were spindle cell, mixed cell, and epithelioid cell UMs in 44, 35, and 21% of patents, respectively. The tumors in patients without MTS were noted to be significantly more likely to have spindle cell-type UM (p<0.0001). Mixed cell and epithelioid cell UMs were more frequently detected in patients with MTS (p<0.0001), which was believed to be due to the presence of epithelioid cells in both cell types. A survival analysis showed that the 3- and 5-year survival rates for patients with spindle cell UM were significantly higher than that for those with epithelioid cell or mixed cell UM (p<0.001); the 3-and 5-year survival rates for spindle cell UM were 78 and 70%, respectively; those for mixed cell UM were 37 and 24%; and those for epithelioid cell UM were 50 and 31%. The similar survival rates for patients with mixed cell or epithelioid cell type UM could conclude that it is advisable to use the binary principle - the presence or absence of epithelioid cells in the tumor, when assessing a UM cell type as a prognostic factor.